Current Sense Amplifiers

The AD8410A is a high voltage, high bandwidth current-sense amplifier. The device features an initial gain of 20 V/V, with a 2.2 MHz bandwidth with a maximum ±0.13% gain error over the entire temperature range. The buffered output voltage directly interfaces with any typical converter. The AD8410A has a minimum DC common-mode rejection ratio (CMRR) of 123 dB from −2 V to +70 V. The AD8410A performs bidirectional current measurements across a shunt resistor in a variety of industrial and automotive applications.

The AD8410A offers breakthrough performance throughout the −40°C to +125°C temperature range. The device features an in-package trim core, which leads to a typical offset drift of ±0.21 μV/°C (based on Box Method, see Figure 56) throughout the operating temperature range and the common-mode voltage range without the need for chopping and autozero clocks (which could lead to intermodulation in the application). The device in- cludes circuitry to achieve a wide input common-mode range and balanced input bias currents, regardless of input differential voltage or common-mode voltage, and circuitry to achieve ultra-low CMRR drift. The device also includes circuitry to enable output accuracy in the presence of pulse-width modulation (PWM) type input common-mode voltages. The AD8410A is available in 8-lead, SOIC_N package and 8-lead, MSOP package.

APPLICATIONS

• In-phase or High-side current sensing in
  • Motor control in BLDC motors, Low-inductance motors
  • Bidirectional 48 V to 12 V DC-DC converters
  • Solenoid controls
  • Power rail monitoring
• Low-side current sensing

Protected by U.S. patent numbers 10,312,865 and 10,587,228.

TThe AD8411A is a high-voltage, high-bandwidth current-sense amplifier. The device features an initial gain of 50 V/V, with a 2.7 MHz bandwidth with a maximum ±0.15% gain error over the entire temperature range. The buffered output voltage directly interfaces with any typical converter. The AD8411A has a minimum DC com- mon-mode rejection ratio (CMRR) of 123 dB from −2 V to +70 V. The AD8411A performs bidirectional current measurements across a shunt resistor in various industrial and automotive applications.

The AD8411A offers breakthrough performance throughout the −40°C to +125°C temperature range. The device features an in-package trim core, which leads to a typical offset drift of ±0.26 μV/°C (based on Box Method, see Figure 56) throughout the operating temperature range and the common-mode voltage range without the need for chopping and auto-zero clocks (which could lead to intermodulation in the application). The device includes circuitry to achieve a wide input common-mode range and balanced input bias currents, regardless of input differential voltage or common-mode voltage, and circuitry to achieve ultra-low CMRR drift. The device also includes circuitry to enable output accuracy in the presence of pulse-width modulation (PWM) type input common-mode voltages. The AD8411A is available in 8-lead, SOIC_N package and 8-lead, MSOP package./p>

APPLICATIONS

• In-phase or High-side current sensing in
• BLDC motors, Low-inductance motors
• Bidirectional 48 V to 12 V DC-DC converters
• Solenoid controls
• Power rail monitoring
• Low-side current sensing

Protected by U.S. patent numbers 10,312,865 and 10,587,228.

The AD8417-2 is a high voltage, high resolution, and dual channel current sense amplifier. It features an initial gain of 60 V/V, with a maximum ±0.3% gain error over the entire temperature range. The AD8417-2 performs bidirectional current measurements across a shunt resistor in a variety of applications, including motor control, power management, and solenoid control.

The AD8417-2 offers breakthrough performance throughout the −40°C to +125°C temperature range. It features a zero drift core, which leads to a typical offset drift of 0.1 μV/°C throughout the operating temperature range and the common-mode voltage range. The device includes EMI filters and patented circuitry to enable output accuracy with pulse-width modulation (PWM) type input common-mode voltages. The typical input offset voltage is ±200 μV.

The AD8417-2 is offered in a small 10-ball 1 mm × 1.9 mm WLCSP. It requires a smaller board area than a typical single-channel current sense amplifier, increasing channel density, without compromising performance.

APPLICATIONS

• High-side current sensing in:
  • Motor controls
  • Solenoid controls
  • Power management
• Low-side current sensing
• Diagnostic protection

The MAX49925 is a bidirectional current-sense amplifier (CSA) with an input common-mode range that extends from -40V to +76V, making it suitable for 48V HEV applications where there are large automotive transients.

This CSA has an extended input protection range of -42V to +80V against reverse-battery and high-voltage spikes. The wider input protection range also helps relax TVS requirements, leading to lower BOM cost and reduced component size.

The MAX49925 is well-suited for phase-current monitoring of inductive loads, such as motors and solenoids, where pulse-width modulation (PWM) is used to control the drive voltage and current.

The MAX49925 uses an improved technique to help reject common-mode input PWM edges with slew rates up to and beyond 500V/μs.

The MAX49925 operates over the full -40°C to +125°C temperature range and runs from a supply voltage of +2.7V to +5.5V. It is available in a 3mm x 3mm, 10-pin TDFN package with side-wettable flanks.

APPLICATIONS

• PWM H-Bridge Motor In-Line/In-Phase/Winding Current Sensing
• Solenoid Current Sensing
• Current Monitoring of Inductive Loads
• Battery Stack Monitors
• High Power DC Motors
• Automotive
• 48V Hybrid and Electric Vehicles (HEV)

The AD8214 is a fast response, high common-mode voltage, current shunt comparator. The device operates on the high side rail of any DC current sensing application, provided the voltage is between 5 V and 65 V. Internally, the AD8214 features a fast comparator that is optimized for high side operation. An internal Zener regulator powers the circuit with respect to the high side DC rail. In addition, user access to this 2.4V regulator, allows for setting a comparator threshold voltage via external resistors. The AD8214 will compare the voltage across the shunt resistor to this user-selected threshold, and the AD8214 output will change states from low to high, indicating the current across the shunt has crossed the threshold level.

The input to output response time of the AD8214 is typically less than 100 ns. This makes the device optimal for overcurrent protection in applications such as motor and solenoid control. Built-in comparator hysteresis means that once the current across the shunt falls back to a normal limit, the AD8214 output will change states to its original level.

The LTC6102/LTC6102HV are versatile, high voltage, highside current sense amplifiers. Their high supply voltage rating allows their use in many high side applications, while the low drift and offset ensure accuracy across a wide range of operating conditions. The LTC6102-1 is a version of the LTC6102 that includes a low power disable mode to conserve system standby power.

The LTC6102/LTC6102HV monitor current via the voltage across an external sense resistor (shunt resistor). Internal circuitry converts input voltage to output current, allowing a small sense signal on a large common mode voltage to be translated to a ground-referred signal. Low DC offset allows the use of very low shunt resistor values and large gain-setting resistors. As a result, power loss in the shunt is reduced.

The wide operating supply and high accuracy make the LTC6102 ideal for a large array of applications, from automotive, to industrial and power management. A maximum input sense voltage of 2V allows a wide range of currents and voltages to be monitored. Fast response makes the LTC6102 the perfect choice for load current warnings and shutoff protection control.

All versions of the LTC6102 are available in 8-lead MSOP and 3mm × 3mm DFN packages.

Applications

• Current Shunt Measurement
• Battery Monitoring
• Remote Sensing
• Load Protection
• Motor Control
• Automotive Controls