Intelligent Motion Control

The MAX22700–MAX22702 are a family of single-channel isolated gate drivers with ultra-high common-mode transient immunity (CMTI) of 300kV/µs (typ). TThe devices are designed to drive silicon-carbide (SiC) or gallium-nitride (GaN) transistors in various inverter or motor control applications with different output gate-drive circuitry and B-side supply voltages. The devices feature variants with output options for gate driver common pin GNDB (MAX22700), Miller Clamp (MAX22701), and adjustable undervoltagelockout UVLO (MAX22702). In addition, variants are offered as differential (D versions) or single-ended (E versions) inputs. All devices have integrated digital galvanic isolation using Maxim’s proprietary process technology. The MAX22700–MAX22702 feature isolation for a withstand voltage rating of 3kV_RMS (narrow SOIC package) or 5kV_RMS (wide SOIC package) for 60 seconds.

All devices support a minimum pulse width of 20ns with a maximum pulse width distortion of 2ns. The part-to-part propagation delay is matched within 2ns (max) at +25°C ambient temperature, and 5ns (max) over the -40°C to +125°C operating temperature range. This feature reduces the power transistor’s dead time, thus improving overall efficiency.

The MAX22700 and the MAX22702 have a maximum R_DSON of 1.25Ω for the low-side driver, and the MAX22701 has an R_DSON of 2.5Ω for the low-side driver. All devices have a maximum R_DSON of 4.5Ω for the high-side driver. See the Ordering Information for suffixes associated with each option.

The MAX22700–MAX22702 are available either in an 8-pin wide-body SOIC package with 8mm creepage and clearance, or in a smaller 8-pin narrow-body SOIC package with 4mm of creepage and clearance. The narrow SOIC package material has a minimum comparative tracking index (CTI) of 600, which gives it a group I rating in creepage tables, while the wide SOIC package material has a minimum CTI of 400, which gives it a group II rating in creepage tables. All devices are rated for operation at ambient temperatures of -40°C to +125°C.

Design Solution: Choose a High CMTI Gate Driver That Cuts Your SiC Switch Dead-Time ›

Applications

• Isolated Gate Driver for Inverters
• Motor Drives
• UPS and PV Inverters

The MAX22700–MAX22702 are a family of single-channel isolated gate drivers with ultra-high common-mode transient immunity (CMTI) of 300kV/µs (typ). TThe devices are designed to drive silicon-carbide (SiC) or gallium-nitride (GaN) transistors in various inverter or motor control applications with different output gate-drive circuitry and B-side supply voltages. The devices feature variants with output options for gate driver common pin GNDB (MAX22700), Miller Clamp (MAX22701), and adjustable undervoltagelockout UVLO (MAX22702). In addition, variants are offered as differential (D versions) or single-ended (E versions) inputs. All devices have integrated digital galvanic isolation using Maxim’s proprietary process technology. The MAX22700–MAX22702 feature isolation for a withstand voltage rating of 3kV_RMS (narrow SOIC package) or 5kV_RMS (wide SOIC package) for 60 seconds.

All devices support a minimum pulse width of 20ns with a maximum pulse width distortion of 2ns. The part-to-part propagation delay is matched within 2ns (max) at +25°C ambient temperature, and 5ns (max) over the -40°C to +125°C operating temperature range. This feature reduces the power transistor’s dead time, thus improving overall efficiency.

The MAX22700 and the MAX22702 have a maximum R_DSON of 1.25Ω for the low-side driver, and the MAX22701 has an R_DSON of 2.5Ω for the low-side driver. All devices have a maximum R_DSON of 4.5Ω for the high-side driver. See the Ordering Information for suffixes associated with each option.

The MAX22700–MAX22702 are available either in an 8-pin wide-body SOIC package with 8mm creepage and clearance, or in a smaller 8-pin narrow-body SOIC package with 4mm of creepage and clearance. The narrow SOIC package material has a minimum comparative tracking index (CTI) of 600, which gives it a group I rating in creepage tables, while the wide SOIC package material has a minimum CTI of 400, which gives it a group II rating in creepage tables. All devices are rated for operation at ambient temperatures of -40°C to +125°C.

Design Solution: Choose a High CMTI Gate Driver That Cuts Your SiC Switch Dead-Time ›

Applications

• Isolated Gate Driver for Inverters
• Motor Drives
• UPS and PV Inverters

The MAX22700–MAX22702 are a family of single-channel isolated gate drivers with ultra-high common-mode transient immunity (CMTI) of 300kV/µs (typ). TThe devices are designed to drive silicon-carbide (SiC) or gallium-nitride (GaN) transistors in various inverter or motor control applications with different output gate-drive circuitry and B-side supply voltages. The devices feature variants with output options for gate driver common pin GNDB (MAX22700), Miller Clamp (MAX22701), and adjustable undervoltagelockout UVLO (MAX22702). In addition, variants are offered as differential (D versions) or single-ended (E versions) inputs. All devices have integrated digital galvanic isolation using Maxim’s proprietary process technology. The MAX22700–MAX22702 feature isolation for a withstand voltage rating of 3kV_RMS (narrow SOIC package) or 5kV_RMS (wide SOIC package) for 60 seconds.

All devices support a minimum pulse width of 20ns with a maximum pulse width distortion of 2ns. The part-to-part propagation delay is matched within 2ns (max) at +25°C ambient temperature, and 5ns (max) over the -40°C to +125°C operating temperature range. This feature reduces the power transistor’s dead time, thus improving overall efficiency.

The MAX22700 and the MAX22702 have a maximum R_DSON of 1.25Ω for the low-side driver, and the MAX22701 has an R_DSON of 2.5Ω for the low-side driver. All devices have a maximum R_DSON of 4.5Ω for the high-side driver. See the Ordering Information for suffixes associated with each option.

The MAX22700–MAX22702 are available either in an 8-pin wide-body SOIC package with 8mm creepage and clearance, or in a smaller 8-pin narrow-body SOIC package with 4mm of creepage and clearance. The narrow SOIC package material has a minimum comparative tracking index (CTI) of 600, which gives it a group I rating in creepage tables, while the wide SOIC package material has a minimum CTI of 400, which gives it a group II rating in creepage tables. All devices are rated for operation at ambient temperatures of -40°C to +125°C.

Design Solution: Choose a High CMTI Gate Driver That Cuts Your SiC Switch Dead-Time ›

Applications

• Isolated Gate Driver for Inverters
• Motor Drives
• UPS and PV Inverters

The MAX22700–MAX22702 are a family of single-channel isolated gate drivers with ultra-high common-mode transient immunity (CMTI) of 300kV/µs (typ). TThe devices are designed to drive silicon-carbide (SiC) or gallium-nitride (GaN) transistors in various inverter or motor control applications with different output gate-drive circuitry and B-side supply voltages. The devices feature variants with output options for gate driver common pin GNDB (MAX22700), Miller Clamp (MAX22701), and adjustable undervoltagelockout UVLO (MAX22702). In addition, variants are offered as differential (D versions) or single-ended (E versions) inputs. All devices have integrated digital galvanic isolation using Maxim’s proprietary process technology. The MAX22700–MAX22702 feature isolation for a withstand voltage rating of 3kV_RMS (narrow SOIC package) or 5kV_RMS (wide SOIC package) for 60 seconds.

All devices support a minimum pulse width of 20ns with a maximum pulse width distortion of 2ns. The part-to-part propagation delay is matched within 2ns (max) at +25°C ambient temperature, and 5ns (max) over the -40°C to +125°C operating temperature range. This feature reduces the power transistor’s dead time, thus improving overall efficiency.

The MAX22700 and the MAX22702 have a maximum R_DSON of 1.25Ω for the low-side driver, and the MAX22701 has an R_DSON of 2.5Ω for the low-side driver. All devices have a maximum R_DSON of 4.5Ω for the high-side driver. See the Ordering Information for suffixes associated with each option.

The MAX22700–MAX22702 are available either in an 8-pin wide-body SOIC package with 8mm creepage and clearance, or in a smaller 8-pin narrow-body SOIC package with 4mm of creepage and clearance. The narrow SOIC package material has a minimum comparative tracking index (CTI) of 600, which gives it a group I rating in creepage tables, while the wide SOIC package material has a minimum CTI of 400, which gives it a group II rating in creepage tables. All devices are rated for operation at ambient temperatures of -40°C to +125°C.

Design Solution: Choose a High CMTI Gate Driver That Cuts Your SiC Switch Dead-Time ›

Applications

• Isolated Gate Driver for Inverters
• Motor Drives
• UPS and PV Inverters

The fido5100 and fido5200 (REM switch) are programmable IEEE 802.3 10 Mbps/100 Mbps Ethernet Internet Protocol Version 6 (IPv6) and Internet Protocol Version 4 (IPv4) switches that support virtually any Layer 2 or Layer 3 protocol. The switches are personalized to support the desired protocol by firmware that is downloaded from a host processor.

The firmware is contained in the real-time Ethernet multiprotocol (REM) switch driver and is downloaded at power-up. The REM switch can be ready for network data operation in less than 4 ms to support fast startup and quick connect type network functionality. The REM switch devices have the same signal assignments as defined in this data sheet.

The fido5100 supports the following protocols: PROFINET real time (RT) and isochronous real time (IRT), EtherNet/IP with and without device level ring (DLR), Modbus TCP, and POWERLINK.

The fido5200 supports the following protocols: EtherCAT and all protocols defined for the fido5100.

The REM switch is intended for use with a host processor. Network operation is handled using the functions and services provided in the REM switch driver. The host processor can implement any protocol stack by integrating it with the REM switch driver. An example application is shown in Figure 11 in the data sheet.

The REM switches are available in a 144-ball chip scale package ball grid array (CSP_BGA) package.

APPLICATIONS

• Industrial automation
  • Process control
  • Managed Ethernet switch

The ADuM7701 is a high performance, second-order, Σ-Δ modulator that converts an analog input signal into a high speed, single-bit data stream, with on-chip digital isolation based on Analog Devices, Inc., iCoupler technology. The devices operate from a 5 V (V_DD1) power supply and accept a pseudo-differential input signal of ±250 mV (±320 mV full scale). The pseudo-differential input is ideally suited to shunt voltage monitoring in high voltage applications where galvanic isolation is required.

The analog input is continuously sampled by a high performance analog modulator, and converted to a ones density digital output stream with a data rate of up to 21 MHz. The original information can be reconstructed with an appropriate digital filter to achieve 86 dB signal to noise ratio (SNR) at 78. l kSPS with a 20 MHz MCLK for the ADuM7701. The serial input/output operates from a 5 V or a 3.3 V supply (V_DD2).

The serial interface is digitally isolated. High speed complementary metal oxide semiconductor (CMOS) technology, combined with monolithic transformer technology, means the on-chip isolation provides outstanding performance characteristics, superior to alternatives such as optocoupler devices. The ADuM7701 device is offered in both 16-lead and 8-lead wide-body SOIC packages and have an operating temperature range of -40°C to +125° C.

Applications

• Shunt curent monitoring
• AC motor controls
• Power and solar inverters
• Wind turbine inverters
• Analog-to-digital and optoisolator replacement

The AD7380/AD7381 are a 16-bit and 14-bit pin-compatible family of dual simultaneous sampling, high speed, low power, successive approximation register (SAR) analog-to-digital converters (ADCs) that operate from a 3.0 V to 3.6 V power supply and feature throughput rates up to 4 MSPS. The analog input type is differential, accepts a wide common-mode input voltage, and is sampled and converted on the falling edge of CS.

An integrated on-chip oversampling block improves dynamic range and reduces noise at lower bandwidths. A buffered internal 2.5 V reference is included. Alternatively, an external reference up to 3.3 V can be used.

The conversion process and data acquisition use standard control inputs allowing simple interfacing to microprocessors or digital signal processors (DSPs). The device is compatible with 1.8 V, 2.5 V, and 3.3 V interfaces using the separate logic supply.

The AD7380/AD7381 are available in a 16-lead lead frame chip scale package (LFCSP) with operation specified from −40°C to +125°C.

Product highlights

1. Dual simultaneous sampling and conversion with two complete ADC functions.
2. Pin-compatible product family.
3. High 4 MSPS throughput rate.
4. Space saving 3 mm × 3 mm LFCSP.
5. An integrated oversampling block to increase dynamic range, reduce noise, and reduce SCLK speed requirements.
6. Differential analog inputs with wide common-mode range.
7. Small sampling capacitor reduces amplifier drive burden.

Applications

• Motor control position feedback
• Motor control current sense
• Sonar
• Power quality
• Data acquisition systems
• Erbium doped fiber amplifier (EDFA) applications
• I and Q demodulation

The ADA4570 is an anisotropic magnetoresistive (AMR) sensor with integrated signal conditioning amplifiers and analog-to-digital converter (ADC) drivers. The ADA4570 produces two differential analog outputs that indicate the angular position of the surrounding magnetic field.

The ADA4570 consists of two die within one package, an AMR sensor, and a fixed gain instrumentation amplifier. The ADA4570 delivers amplified differential cosine and sine output signals, with respect to the angle, when the magnetic field is rotating in the x-axis and the y-axis (x-y) plane. The output voltage range is ratiometric to the supply voltage.

The sensor contains two Wheatstone bridges, at a relative angle of 45° to one another. A complete rotation of a dipole magnet produces two periods on the sinusoidal outputs. Therefore, the magnetic angle (α) calculated from the SIN and COS differential outputs represents the physical orientation of the magnet with respect to the ADA4570 in the 0° to 180° measurement range. Within a homogeneous field in the x-y plane, the output signals of the ADA4570 are independent of the physical placement in the z direction (air gap).

The ADA4570 is available in an 8-lead SOIC package.

APPLICATIONS

• Absolute position measurement (linear and angle)
• Brushless dc motor control and positioning
• Actuator control and positioning
• Contactless angular measurement and detection
• Magnetic angular position sensing

The ADA4571 is an anisotropic magnetoresistive (AMR) sensor with integrated signal conditioning amplifiers and ADC drivers. The ADA4571 produces two analog outputs that indicate the angular position of the surrounding magnetic field.

The ADA4571 consists of two die within one package, an AMR sensor, and a fixed gain (G = 40 nominally) instrumentation amplifier. The ADA4571 delivers clean and amplified cosine and sine output signals related to the angle of a rotating magnetic field. The output voltage range is ratiometric to the supply voltage.

The sensor contains two Wheatstone bridges, at a relative angle of 45° to one another. A rotating magnetic field in the x-y sensor plane delivers two sinusoidal output signals with the double frequency of the angle (α) between sensor and magnetic field direction. Within a homogeneous field in the x-y plane, the output signals are independent of the physical placement in the z direction (air gap).

The ADA4571 is available in an 8-lead SOIC package.

Product Highlights

1. Contactless angular measurement.
2. Measures magnetic field direction rather than field intensity.
3. Minimum sensitivity to air gap variations.
4. Large working distance.
5. Excellent accuracy, even for weak saturation fields.
6. Minimal thermal and lifetime drift.
7. Negligible hysteresis.
8. Single chip solution.

Applications

• Absolute position measurement (linear and angle)
• Brushless dc motor control and positioning
• Actuator control and positioning
• Contactless angular measurement and detection
• Magnetic angular position sensing

The ADuM4221/ADuM4221-1/ADuM4221-2 are 4 A isolated, half bridge gate drivers that employ the Analog Devices, Inc., iCoupler^® technology to provide independent and isolated high-side and low-side outputs. The ADuM4221/ADuM4221-1/ADuM4221-2 provide 5700 V rms isolation in an increased creepage wide body, 16-lead SOIC_IC. Combining high speed CMOS and monolithic transformer technology, these isolation components provide outstanding performance characteristics superior to the alternatives, such as the combination of pulse transformers and gate drivers.

The isolators operate with a logic input voltage ranging from 2.5 V to 6.5 V, providing compatibility with lower voltage systems. In comparison to gate drivers employing high voltage level translation methodologies, the ADuM4221/ADuM4221-1/ADuM4221-2 offer the benefit of true, galvanic isolation between the input and each output.

The ADuM4221/ADuM4221-1/ADuM4221-2 each have built in overlap protection and allow dead time adjustment. A single resistor between the dead time pin (DT) and the GND¹ pin sets the dead time on the secondary side between the high-side and the low-side outputs.

An internal thermal shutdown (TSD) sets outputs low if the internal temperature on the ADuM4221/ADuM4221-1/ADuM4221-2 exceeds the TSD temperature. As a result, the ADuM4221/ADuM4221-1/ADuM4221-2 provide reliable control over the switching characteristics of the insulated gate bipolar transistor (IGBT)/metal-oxide semiconductor field effect transistor (MOSFET) configurations over a wide range of positive or negative switching voltages.

Applications

• Switching power supplies
• Isolated IGBT/MOSFET gate drives
• Industrial inverters
• Gallium nitride (GaN)/silicon carbide (SiC) compatible

¹ Protected by U.S. Patents 5,952,849; 6,873,065; 7,075,239. Other patents pending.

The ADuM4135 is a single-channel gate driver specifically optimized for driving insulated gate bipolar transistors (IGBTs). Analog Devices, Inc., iCoupler^® technology provides isolation between the input signal and the output gate drive.

The ADuM4135 includes a Miller clamp to provide robust IGBT turn-off with a single-rail supply when the gate voltage drops below 2 V (typical). Operation with unipolar or bipolar secondary supplies is possible, with or without the Miller clamp operation.

The Analog Devices chip scale transformers also provide isolated communication of control information between the high voltage and low voltage domains of the chip. Information on the status of the chip can be read back from dedicated outputs. Control of resetting the device after a fault on the secondary is performed on the primary side of the device.

Integrated onto the ADuM4135 is a desaturation detection circuit that provides protection against high voltage short-circuit IGBT operation. The desaturation protection contains noise reducing features such as a 370 ns (typical) masking time after a switching event to mask voltage spikes due to initial turn-on. An internal 537 μA (typical) current source allows low device count and the internal blanking switch allows the addition of an external current source if more noise immunity is needed.

The secondary UVLO is set to 11.67 V (typical) with common IGBT threshold levels taken into consideration.

APPLICATIONS

• MOSFET/IGBT gate drivers
• PV inverters
• Motor drives
• Power supplies
• Automotive

The ADuM6020/ADuM6028¹ are isoPower^®, integrated, isolated dc-to-dc converters. Based on the Analog Devices, Inc., iCoupler^® technology, these dc-to-dc converters provide regulated, isolated power that is below CISPR22 Class B limits at full load on a 2‑layer printed circuit board (PCB) with ferrites. Common voltage combinations and the associated current output levels are shown in Table 1 through Table 4 in the data sheet.

The ADuM6020/ADuM6028 eliminate the need to design and build isolated dc-to-dc converters in applications up to 500 mW. The iCoupler chip scale transformer technology is used for the magnetic components of the dc-to-dc converter. The result is a small form factor, isolated solution.

The ADuM6020/ADuM6028 isolated dc-to-dc converters provide two different package variants: the ADuM6020 in a wide-body, 16-lead SOIC_IC package, and the ADuM6028 in the space-saving, 8-lead, wide-body SOIC_IC package. For 5 V input operations, use the ADuM6020-5BRIZ and the ADuM6028-5BRIZ. For 3.3 V input to 3.3 V output operations, use the ADuM6020-3BRIZ and the ADuM6028-3BRIZ. See the Pin Configuration and Function Descriptions section and the Ordering Guide in the data sheet for more information.

APPLICATIONS

• RS-485/RS-422/CAN transceiver power
• Power supply start-up bias and gate drives
• Isolated sensor interfaces
• Automotive on-board charger (OBC) and dc to dc
• Industrial PLCs

¹ Protected by U.S. Patents 5,952,849; 6,873,065; 6,903,578; and 7,075,329. Other patents are pending.

The ADIN1300 is a low power, single port, Gigabit Ethernet transceiver with low latency and power consumption specifications primarily designed for industrial Ethernet applications.

This design integrates an energy efficient Ethernet (EEE) physical layer device (PHY) core with all associated common analog circuitry, input and output clock buffering, management interface and subsystem registers, and MAC interface and control logic to manage the reset and clock control and pin configuration.

The ADIN1300 is available in a 6 mm × 6 mm, 40-lead lead frame chip scale package (LFCSP). The device operates with a minimum of 2 power supplies, 0.9 V and 3.3 V, assuming the use of a 3.3 V MAC interface supply. For maximum flexibility in system level design, a separate VDDIO supply enables the management data input/output (MDIO) and MAC interface supply voltages to be configured independently of the other circuitry on the ADIN1300, allowing operation at 1.8 V, 2.5 V, or 3.3 V. At power-up, the ADIN1300 is held in hardware reset until each of the supplies has crossed its minimum rising threshold value. Brown-out protection is provided by monitoring the supplies to detect if one or more supply drops below a minimum falling threshold (see Table 19 on the datasheet), and holding the device in hardware reset until the power supplies return and satisfy the power-on reset (POR) circuit.

The MII management interface (also referred to as MDIO interface) provides a 2-wire serial interface between a host processor or MAC (also known as management station (STA)) and the ADIN1300, allowing access to control and status information in the PHY core management registers. The interface is compatible with both the IEEE 802.3 Standard Clause 22 and Clause 45 management frame structures.

The ADIN1300 can support cable lengths up to 150 meters at Gigabit speeds and 180 meters when operating at 100 Mbps or 10 Mbps.

APPLICATIONS

• Industrial automation
• Process control
• Factory automation
• Robotics/motion control
• Time sensitive networking (TSN)
• Building automation
• Test and measurement
• Industrial internet of things (IoT)

The ADIN1200 is a low power, single-port, 10 Mbps and 100 Mbps Ethernet transceiver with low latency specifications designed for industrial Ethernet applications.

This design integrates an energy efficient Ethernet (EEE) physical layer device (PHY) core with all associated common analog circuitry, input and output clock buffering, management interface and subsystem registers, and media access control (MAC) interface and control logic to manage the reset, clock control and pin configuration.

The ADIN1200 is available in a 5 mm × 5 mm, 32-lead lead frame chip scale package (LFCSP) and can operate with a single 3.3 V supply, assuming the use of a 3.3 V MAC interface supply. For maximum flexibility in system level design, a separate VDDIO supply enables the management data input/output (MDIO) and MAC interface supply voltages to be configured independently of the other circuitry on the ADIN1200 allowing operation at 1.8 V, 2.5 V, or 3.3 V. At power-up, the ADIN1200 is held in hardware reset until each of the supplies has crossed its minimum rising threshold value and the power is considered good. Brownout protection is provided by monitoring the supplies to detect if one or more of them drops below a minimum falling threshold and holding the device in hardware reset until the power supplies return and satisfy the power-on-reset (POR) circuit.

The MII management interface (also referred to as MDIO interface) provides a 2-wire serial interface between a host processor or MAC and the ADIN1200, allowing access to control and status information in the PHY core management registers. The interface is compatible with both IEEE^® 802.3^™ Standard Clause 22 and Clause 45 management frame structures.

The ADIN1200 can support cable lengths up to 180 meters.

APPLICATIONS

• Industrial automation
• Process control
• Factory automation
• Robotics and motion control
• Time sensitive networking (TSN)
• Building automation
• Test and measurement
• Industrial internet of things (IoT)

The ADuM3150 is a 6-channel SPIsolator^™ digital isolator optimized for isolated serial peripheral interfaces (SPIs). Based on the Analog Devices, Inc., iCoupler^® chip scale transformer technology, the low propagation delay in the CLK, MO/SI, MI/SO, and SS SPI bus signals supports SPI clock rates of up to 17 MHz. These channels operate with 14 ns propagation delay and 1 ns jitter to optimize timing for SPI.

The ADuM3150 isolator also provides two additional independent low data rate isolation channels, one channel in each direction. Data in the slow channels is sampled and serialized for a 250 kbps data rate with 2.5 μs of jitter.

The ADuM3150 supports a delay clock output on the master side of the device. This output can be used with an additional clocked port on the master to support 40 MHz clock performance. See the Delay Clock section for more information.

Applications

• Industrial programmable logic controllers (PLC)
• Sensor isolation

The ADuM3190 is an isolated error amplifier based on Analog Devices, Inc., iCoupler^® technology. The ADuM3190 is ideal for linear feedback power supplies. The primary side controllers of the ADuM3190 enable improvements in transient response, power density, and stability as compared to commonly used optocoupler and shunt regulator solutions.

Unlike optocoupler-based solutions, which have an uncertain current transfer ratio over lifetime and at high temperatures, the ADuM3190 transfer function does not change over its lifetime, and it is stable over a wide temperature range of −40°C to +125°C.

Included in the ADuM3190 is a wideband operational amplifier for a variety of commonly used power supply loop compensation techniques. The ADuM3190 is fast enough to allow a feedback loop to react to fast transient conditions and overcurrent conditions. Also included is a high accuracy 1.225 V reference to compare with the supply output setpoint.

The ADuM3190 is packaged in a small 16-lead QSOP package for a 2.5 kV rms isolation voltage rating.

Applications

• Linear power supplies
• Inverters
• Uninterruptible Power Supply (UPS)
• DOSA-compatible modules
• Voltage monitors
• Automotive systems

The compact two-chip circuit shown in Figure 1 provides a contactless anisotropic magnetoresistive (AMR) measurement solution ideal for either angle or linear position measurements. The two-chip system is capable of providing better than 0.2° angular accuracy over 180°, and linear accuracy of 2 mil (0.002 inch) over a 0.5 inch range, depending on the size of the magnet used.

The circuit is ideal for applications where high speed, accurate, noncontact angle and length measurements are critical, such as machine tool speed control, crane angle control, brushless dc motors, and other industrial or automotive applications.

The circuits shown in Figure 1 demonstrate proven and tested electromagnetic compatibility (EMC) compliant solutions for three protection levels for popular RS-485 communication ports using the ADM3485E transceiver. Each solution was tested and characterized to ensure that the dynamic interaction between the transceiver and the protection circuit components functions correctly together to protect against the electrostatic discharge (ESD), electrical fast transients (EFT), and surge immunity specified in IEC 61000-4-2, IEC 61000-4-4, and IEC 61000-4-5, respectively. The circuits offer proven protection for RS-485 interfaces using the ADM3485E to the ESD, EFT, and surge levels often encountered in harsh environments.

The circuit shown in Figure 1 monitors current in systems with high positive common-mode dc voltages of up to +500 V with less than 0.2% error. The load current passes through a shunt resistor, which is external to the circuit. The shunt resistor value is chosen so that the shunt voltage is approximately 500 mV at maximum load current.

The AD8212 accurately amplifies a small differential input voltage in the presence of large positive common-mode voltages greater than 500 V when used in conjunction with an external PNP transistor.

Galvanic isolation is provided by the ADuM5402 quad channel isolator. This is not only for protection but to isolate the downstream circuitry from the high common-mode voltage. In addition to isolating the output data, the ADuM5402 digital isolator can also supply isolated +3.3 V for the circuit.

The measurement result from the AD7171 is provided as a digital code utilizing a simple 2-wire, SPI-compatible serial interface.

This combination of parts provides an accurate high voltage positive rail current sense solution with a small component count, low cost, and low power.

The circuit shown in Figure 1 is a complete low cost implementation of an analog-to-analog isolator. The circuit provides isolation of 2500 V rms (1 minute per UL 1577).

The circuit is based on the AD7400A, a second-order, sigma-delta (Σ-Δ) modulator with a digitally isolated 1-bit data stream output. The isolated analog signal is recovered with a fourth-order active filter based on the dual, low noise, rail-to-rail AD8646 op amp. With the ADuM5000 as the power supply for the isolated side, the two sides are completely isolated and use only one power supply for the system. The circuit has 0.05% linearity and benefits from the noise shaping provided by the modulator of the AD7400A and the analog filter. The applications of the circuit include motor control and shunt current monitoring, and the circuit is also a good alternative to isolation systems based on optoisolators.

The circuit shown in Figure 1 is a complete adjustment-free linear variable differential transformer (LVDT) signal conditioning circuit. This circuit can accurately measure linear displacement (position).

The LVDT is a highly reliable sensor because the magnetic core can move without friction and does not touch the inside of the tube. Therefore, LVDTs are suitable for flight control feedback systems, position feedback in servomechanisms, automated measurement in machine tools, and many other industrial and scientific electromechanical applications where long term reliability is important.

This circuit uses the AD698 LVDT signal conditioner that contains a sine wave oscillator and a power amplifier to generate the excitation signals that drive the primary side of the LVDT. The AD698 also converts the secondary output into a dc voltage. The AD8615 rail-to-rail amplifier buffers the output of the AD698 and drives a low power 12-bit successive approximation analog-to-digital converter (ADC). The system has a dynamic range of 82 dB and a system bandwidth of 250 Hz, making it ideal for precision industrial position and gauging applications.

The signal conditioning circuitry of the system consumes only 15 mA of current from the ±15 V supply and 3 mA from the +5 V supply.

This circuit note discusses basic LVDT theory of operation and the design steps used to optimize the circuit shown in Figure 1 for a chosen bandwidth, including noise analysis and component selection considerations.