ADPD105BCBZR7

Overview

The ADPD105BCBZR7 is a multifunction photometric front end from Analog Devices, featuring an integrated 14-bit analog-to-digital converter (ADC) and a 20-bit burst accumulator. It supports flexible LED drivers with peak currents up to 370 mA and offers sampling frequencies ranging from 0.122 Hz to 3820 Hz. The device operates on a single 1.8 V supply (1.7 V to 1.9 V range) and utilizes an I²C interface for control and data readout. Designed for low power consumption, it includes ambient light rejection capabilities without requiring external optical filters.

Feature Summary

• Integrated 14-bit ADC with a 20-bit burst accumulator enabling up to 27 bits of resolution per data read through sample averaging.
• Three independent LED drivers capable of delivering up to 370 mA peak current with flexible pulse timing.
• I²C serial interface operating at 400 kHz for configuration and data retrieval.
• Best-in-class ambient light rejection using synchronous detection techniques.

Applications

• Wearable health and fitness monitors
• Clinical measurements such as SpO2 monitoring
• Industrial monitoring systems
• Background light measurement applications

Procurement Notes

Verify the specific package type associated with the BCBZ suffix against official documentation, as the ADPD105 family includes both WLCSP and LFCSP variants. Confirm that the I²C interface requirement aligns with this model, distinguishing it from SPI-only versions like the ADPD106 or ADPD107. Ensure compatibility with 1.8 V logic levels for the SDA and SCL lines.

Selection Notes

Select the ADPD105BCBZR7 when an I²C interface is required rather than SPI. Consider the 20-bit burst accumulator for high-resolution needs in low-light conditions. Ensure the application can accommodate the 1.8 V core voltage and verify that the photodiode capacitance remains below 100 pF for optimal performance. Check if the LFCSP or WLCSP package variant matches the PCB layout constraints.

Part Context

The ADPD105 belongs to a family of photometric front ends that also includes the ADPD106 and ADPD107. While all three share similar internal architectures and LED driver capabilities, they differ primarily in their digital interfaces. The ADPD105 is distinguished by its support for the I²C protocol, whereas the ADPD106 and ADPD107 are restricted to SPI communication only.

Replacement Considerations

Direct replacements within the same family include the ADPD106 and ADPD107, provided the system design can be adapted from I²C to SPI. Verify pin compatibility and register mapping differences between the I²C and SPI versions before substitution.