The ADPD7008 is a highly integrated analog front end (AFE) designed for measuring various vital signals. The optical channel is designed as an optical transceiver, stimulating up to eight light emitting diodes (LEDs) and measuring the return signal on up to four separate current inputs. The signal chain rejects signal offsets and corruption from asynchronous modulated interference, typically from ambient light, eliminating the need for optical filters or externally controlled DC cancellation circuitry. The data output and functional configuration use a serial port interface (SPI) on the ADPD7008. The control circuitry includes flexible LED signaling and synchronous detection, digital filters, digital wave generators, and configurable filters. The ADPD7008 is available in a 2.795 mm × 2.560 mm, 0.40 mm pitch, 36-ball WLCSP. APPLICATIONS * Wearable health and fitness monitors: heart rate, heart rate variability, and saturation level of pulse oxygen * Clinical patient monitors: small bed side patient, home portable patient, and small remote patient * Industrial monitoring: particle, aerosol, and gas detection * Optical channel * 4 input channels with multiple operation modes for various sensor measurements * 4-channel processing with simultaneous sampling * 12 programmable time slots for synchronized sensor measurements * Flexible input multiplexing to support single-ended sensor measurements * 8 LED drivers, 2 of which can be driven simultaneously * Flexible sampling rate from 0.004 Hz to 9 kHz using internal oscillators