Products
WCS8000
$0.00
Wide Dynamic Range CMOS Photo Sensor with Auto-gain Adjust Feedback
- On die photo diode
- 2mA output buffer
- Operate from 150 Hz to 128KHz
- Auto Adjustable Gain up to 35dB
- 2KV ESD Protection
- Ambient Light Immunity
- 3uW to 65W Input Power
- Meets ANSIC 12-18 Port Req
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Design Description
The WCS8000 is an integrated photo sensor that provides a wide range of optical sensitivity. The photo diode converts light signal to electrical signal. A transimpedance amplifier will gain the signal and convert it to a voltage output. The trans-impedance gain is autoadjustable to meet the required device sensitivity 3u W to 65u W. The low pass filter (LPF) and high pass filter (HPF) filter out the low and high frequency noise and provide the auto-gain adjustment over the required sensitivity. Conditioning circuit is added to generate a 128 KHz digital output signal with constant duty cycle. The output buff er will provide a maximum output current drive of 2mA.
Functional Block Description
The WCS8000 is an integrated photo sensor that provides the following functional blocks:
- On die photo diode converts the light signal to electrical signal.
- Trans-impedance with a low-pass filter with 1.4MHz cutoff frequency and an integrator feedback circuit that amplifies the signal and attenuates the low frequency component of the signal (i.e. DC, sunlight and indoor/outdoor lights).
- High-pass filter to remove the DC off set and further amplifies the signal.
- Automatic gain control circuit determines the gain level of the trans-impedance amplifier and high-pass filter.
- Peak detector, comparator and output driver convert the peak signal into digital output signals.
- Voltage reference and clock generator circuits generate the reference voltage and internal clock for the ASIC.
- On die photo diode converts the light signal to electrical signal.
