User Interaction and Cabin Sensing
The ADP2140 includes a high efficiency, low quiescent 600 mA stepdown dc-to-dc converter and a 300 mA LDO packaged in a small 10-lead 3 mm × 3 mm LFCSP. The total solution requires only four tiny external components.
The buck regulator uses a proprietary high speed current-mode, constant frequency pulse-width modulation (PWM) control scheme for excellent stability and transient response. To ensure the longest battery life in portable applications, the ADP2140 has a power saving variable frequency mode to reduce switching frequency under light loads.
The LDO is a low quiescent current, low dropout linear regulator designed to operate in a split supply mode with VIN2 as low as 1.65 V. The low input voltage minimum allows the LDO to be powered from the output of the buck regulator increasing efficiency and reducing power dissipation. The ADP2140 runs from input voltages of 2.3 V to 5.5 V allowing single Li+/Li− polymer cell, multiple alkaline/NiMH cell, PCMCIA, and other standard power sources.
All versions include an internal power switch and a synchronous rectifier for minimal external part count and high efficiency. ADP2140 includes a power-good pin, soft start, and internal compensation. Numerous power sequencing options are userselectable through two enable inputs. In autosequencing mode, the highest voltage output enables on the rising edge of EN1. During logic controlled shutdown, the input disconnects from the output and draws less than 100 nA from the input source. Other key features include: undervoltage lockout to prevent deep battery discharge, softstart to prevent input current overshoot at startup, and both short-circuit protection and thermal overload protection circuits to prevent damage in adverse conditions.
When the ADP2140 is used with two 0603 capacitors, one 0402 capacitor, one 0402 resistor, and one 0805 inductor, the total solution size is about 90 mm2 resulting in the smallest footprint solution to meet a variety of portable applications.Applications
- Mobile phones
- Personal media players
- Digital camera and audio devices
- Portable and battery-powered equipment
The AD8232 is an integrated signal conditioning block for ECG and other biopotential measurement applications. It is designed to extract, amplify, and filter small biopotential signals in the presence of noisy conditions, such as those created by motion or remote electrode placement. This design allows for an ultralow power analog-to-digital converter (ADC) or an embedded microcontroller to acquire the output signal easily.
The AD8232 can implement a two-pole high-pass filter for eliminating motion artifacts and the electrode half-cell potential. This filter is tightly coupled with the instrumentation architecture of the amplifier to allow both large gain and high-pass filtering in a single stage, thereby saving space and cost.
An uncommitted operational amplifier enables the AD8232 to create a three-pole low-pass filter to remove additional noise. The user can select the frequency cutoff of all filters to suit different types of applications.
To improve common-mode rejection of the line frequencies in the system and other undesired interferences, the AD8232 includes an amplifier for driven lead applications, such as right leg drive (RLD).
The AD8232 includes a fast restore function that reduces the duration of otherwise long settling tails of the high-pass filters. After an abrupt signal change that rails the amplifier (such as a leads off condition), the AD8232 automatically adjusts to a higher filter cutoff. This feature allows the AD8232 to recover quickly, and therefore, to take valid measurements soon after connecting the electrodes to the subject.
The AD8232 is available in a 4 mm × 4 mm, 20-lead LFCSP package. Performance is specified from 0°C to 70°C and is operational from −40°C to +85°C.
- Fitness and activity heart rate monitors
- Portable ECG
- Remote health monitors
- Gaming peripherals
- Biopotential signal acquisition
The ADuCM3027/ADuCM3029 microcontroller units (MCUs) are ultra low power microcontroller systems with integrated power management for processing, control, and connectivity. The MCU system is based on the ARM Cortex-M3 processor, a collection of digital peripherals, embedded SRAM and flash memory, and an analog subsystem which provides clocking, reset, and power management capability in addition to an analog-to-digital converter (ADC) subsystem.
The following are the key features of the ADuCM3027/ADuCM3029 MCUs:
- Industry leading ultralow power consumption.
- SensorStrobe™ for precise time synchronized sampling of external sensors.
- Works in hibernate mode, resulting in drastic current reduction in system solutions. Current consumption reduces by 10 times when using, for example, the ADXL363 accelerometer.
- Software intervention is not required after setup.
- No pulse drift due to software execution.
- Leading edge security.
- Fast encryption provides read protection to customer algorithms.
- Write protection prevents device reprogramming by unauthorized code.
- Robust operation.
- Full voltage monitoring in deep sleep modes.
- ECC support on flash.
- Parity error detection on SRAM memory.
- Failure detection of 32 kHz LFXTAL via interrupt.
- Internet of Things (IoT)
- Smart machine, smart metering, smart building, smart city, smart agriculture
- Fitness and clinical
The ADPD144RI is a highly integrated, photometric front end optimized for photoplethysmography (PPG) detection of blood oxygenation (SpO2) by synchronous detection in red and infrared wavelengths. Synchronous measurement allows rejection of both dc and ac ambient light interference with extremely low power consumption.
The module combines highly efficient, light emitting diode (LED) emitters and a sensitive 4-channel, deep diffusion photodiode (PD1 to PD4) with a custom application specific integrated circuit (ASIC) in a compact package that provides optical isolation between the integrated LED emitters and the detection photodiodes to improve through tissue, signal-tonoise ratio (SNR).
The ASIC consists of a 4-channel analog front end (AFE) with two independently configurable datapaths with separate gain and filter settings, a 14-bit analog-to-digital converter (ADC) with a burst accumulator, two flexible, independently configurable, LED drivers, and a digital control block. The digital control block provides AFE and LED timing, signal processing, and communication. Data output and functional configuration occur over a 1.8 V I2C interface.
- Optical heart rate monitoring
- Reflective SpO2 measurement
The ADPD105/ADPD106/ADPD107 are highly efficient, photometric front ends, each with an integrated 14-bit analog-to-digital converter (ADC) and a 20-bit burst accumulator that works with flexible light emitting diode (LED) drivers. The accumulator is designed to stimulate an LED and measure the corresponding optical return signal. The data output and functional configuration occur over a 1.8 V I2C interface on the ADPD105 or SPI on the ADPD106 and ADPD107. The control circuitry includes flexible LED signaling and synchronous detection.
The analog front end (AFE) features best-in-class rejection of signal offset and corruption due to modulated interference commonly caused by ambient light.
Couple the ADPD105/ADPD106/ADPD107 with a low capacitance photodiode of <100 pF for optimal performance. The ADPD105/ADPD106/ADPD107 can be used with any LED. The ADPD105 is available in a 2.46 mm × 1.4 mm WLCSP and a 4 mm × 4 mm LFCSP. The SPI only versions, ADPD106 and ADPD107, are available in a 2.46 mm × 1.4 mm WLCSP.
- Wearable health and fitness monitors
- Clinical measurements, for example, SpO2
- Industrial monitoring
- Background light measurements
Product Selection Guide