Packaging information
| Package | Pins DSBGA (YZP) | 15 |
| Operating temperature range (°C) -20 to 70 |
| Package qty | Carrier 250 | SMALL T&R |
Features for the AFE4404
- Transmitter:
- Supports Common Anode LED Configuration
- Dynamic Range: 100 dB
- 6-Bit Programmable LED Current to 50 mA (Extendable to 100 mA)
- Programmable LED On-Time
- Simultaneous Support of 3 LEDs for Optimized SPO2, HRM, or Multi-Wavelength HRM
- Receiver:
- 24-Bit Representation of the Current Input from a Photodiode in Twos Complement Format
- Individual DC Offset Subtraction DAC at TIA Input for Each LED and Ambient Phase
- Digital Ambient Subtraction at ADC Output
- Programmable Transimpedance Gain:
10 kΩ to 2 MΩ - Dynamic Range: 100 dB
- Average Current Less Than 200 µA for PPG Signal Acquisition
- Pulse Frequency: 10 SPS to 1000 SPS
- Flexible Pulse Sequencing and Timing Control
- Flexible Clock Options:
- External Clocking:
4-MHz to 60-MHz Input Clock - Internal Clocking: 4-MHz Oscillator
- External Clocking:
- I2C Interface
- Operating Temperature Range: –20°C to 70°C
- 2.6-mm × 1.6-mm DSBGA Package, 0.5-mm Pitch
- Supplies: Rx: 2 V to 3.6 V, Tx: 3 V to 5.25 V,
IO: 1.8 V to 3.6 V
Description for the AFE4404
The AFE4404 is an analog front-end (AFE) for optical bio-sensing applications, such as heart-rate monitoring (HRM) and saturation of peripheral capillary oxygen (SpO2). The device supports three switching light-emitting diodes (LEDs) and a single photodiode. The current from the photodiode is converted into voltage by the transimpedance amplifier (TIA) and digitized using an analog-to-digital converter (ADC). The ADC code can be read out using an I2C interface. The AFE also has a fully-integrated LED driver with a 6-bit current control. The device has a high dynamic range transmit and receive circuitry that helps with the sensing of very small signal levels.