The AFE4490 is a fully-integrated analog front-end (AFE) that is ideally suited for pulse-oximeter applications. The device consists of a low-noise receiver channel with a 22-bit analog-to-digital converter (ADC), an LED transmit section, and diagnostics for sensor and LED fault detection. The device is a very configurable timing controller. This flexibility enables the user to have complete control of the device timing characteristics. To ease clocking requirements and provide a low-jitter clock to the device, an oscillator is also integrated that functions from an external crystal. The device communicates to an external microcontroller or host processor using an SPI™ interface.
The device is a complete AFE solution packaged in a single, compact VQFN-40 package (6 mm × 6 mm) and is specified over the operating temperature range of –40°C to 85°C.
|Part number||Order||Number of input channels||Resolution (Bits)||Interface||Number of LEDs||Features||Operating temperature range (C)||Package Group||Package size: mm2:W x L (PKG)||Approx. price (US$)|
||1||22||Serial SPI||2||Optical biosensing||-40 to 85||VQFN | 40||40VQFN: 36 mm2: 6 x 6 (VQFN | 40)||7.95 | 1ku|
||1||22||SPI||2||Optical biosensing||0 to 70||VQFN | 40||40VQFN: 36 mm2: 6 x 6 (VQFN | 40)||2.95 | 1ku|
||1||22||SPI||3||Optical biosensing||-20 to 70||DSBGA | 36||See datasheet (DSBGA)||3.25 | 1ku|
||1||24||I2C||3||Optical biosensing||-20 to 70||DSBGA | 15||See datasheet (DSBGA)||2.28 | 1ku|
|AFE4405||Samples not available||2||24||
|3||Optical biosensing||-20 to 70||2.50 | 1ku|
|AFE4410||Samples not available||3||24||
|4||Optical biosensing||-20 to 70||2.65 | 1ku|
|AFE4900||Samples not available||3||24||
|4||Optical biosensing||-20 to 70||2.75 | 1ku|