The AFE4900 device is an analog front-end (AFE) for synchronized electrocardiogram (ECG), photoplethysmogram (PPG) signal acquisition. The device can also be used for optical bio-sensing applications, such as heart-rate monitoring (HRM) and saturation of peripheral capillary oxygen (SpO2). The PPG signal chain supports up to four switching light-emitting diodes (LEDs) and up to three photodiodes (PDs). The LEDs can be switched on using a fully integrated LED driver. The current from the photodiode is converted into voltage by the transimpedance amplifier (TIA) and digitized using an analog-to-digital converter (ADC). The ECG signal chain has an instrumentation amplifier (INA) with a programmable gain that interfaces to the same ADC. A right-leg drive (RLD) amplifier set can be used to the bias for the ECG input pins. AC and dc lead-off detect schemes are supported. The ADC codes from the PPG and ECG phases can be stored in a 128-sample first in, first out (FIFO) block and read out using either an I2C or a serial programming interface (SPI) interface.
All trademarks are the property of their respective owners.
|Number of input channels|
|Number of LEDs|
|Operating Temperature Range (C)|
|Package Size: mm2:W x L (PKG)|
|Approx. Price (US$)|
|Optical biosensing||Optical biosensing||Optical biosensing||Optical biosensing||Optical biosensing||Optical biosensing|
|-20 to 70||-20 to 70||-20 to 70||-20 to 70||-40 to 85|
|DSBGA | 36||DSBGA | 15||VQFN | 40|
|See datasheet (DSBGA)||See datasheet (DSBGA)||40VQFN: 36 mm2: 6 x 6 (VQFN | 40)|
|2.75 | 1ku||3.25 | 1ku||2.28 | 1ku||2.50 | 1ku||2.65 | 1ku||7.95 | 1ku|
|Order Now||Order Now||Order Now||Order Now||Order Now||Order Now|