Vishay Semiconductors VCNL4020X01 proximity and ambient light sensor

The VCNL4020X01 from Vishay Semiconductors is a proximity and ambient light optical sensor with an operating temperature range to 105°C. The product combines an IR emitter, a photo-pin-diode for proximity, an ambient light detector, a signal processing IC and a 16-bit ADC in one 4.8 x 2.3 x 0.8 mm rectangular leadless package.

The unit saves power by turning off the display backlight until a user is detected, while using its integrated ambient light function for display/keypad adaptive brightness control and rear-view mirror dimming. The device eliminates the need for additional light barriers and optical alignment of the IR emitter and photo diode.

The product can function at any depth or air gap below the glass window and can be assembled on the main PCB near other components. The interrupt function enables the sensor to work independently until a predefined proximity or ambient light event occurs.

The product provides a programmable LED drive current from 10 to 200 mA in 10 mA steps, allowing distances up to 200 mm. The device offers good ambient light suppression by modulating the infrared signal. The emitter wavelength peaks at 890 nm and has no visible ‘red tail’.

The ambient light photo-pin-diode offers a 16-bit dynamic range for ambient light detection from 0.25 lux to 16 klux. The sensor offers 100 Hz and 120 Hz flicker noise rejection. Featuring standby current consumption of 1.5 µA, the device offers a supply voltage range of 2.5 to 3.6 V and I2C bus voltage range from 1.7 to 5 V.