Vishay has introduced a new type of infrared (IR) sensor designed to provide fast, low-cost proximity sensing in a variety of systems. The TSSP4056 is the industry's first fixed gain sensor, which includes a band-pass filter tuned to 56kHz, with a monotonic sensitivity and frequency response curve from 30kHz to 54kHz. The device can detect modulated pulses from a separate IR transmitter, with a high sensitivity of 0.4 mW / m², and as demonstrated using the company's Fast Proximity Sensor software, it can achieve rapid readings in 5ms using successive approximation techniques.
Generally, the proximity sensor determines the threshold transmitter power of a newly detected object by changing the drive current of the transmitter to determine the distance of the object. This technology requires an expensive DAC to drive the transmitter. However, the TSSP4056 determines the distance by changing the carrier frequency used to drive the transmitter from 30kHz to 54kHz to find the threshold frequency at which the sensor only detects objects. This approach does not require the microcontroller to include a DAC, which reduces the overall solution cost.
The devices released today provide proximity sensing from 10cm to 2m, and> 4 times the dynamic range from the lowest to the highest sensitivity. TSSP4056 is used as a proximity sensor and is ideal for detecting object distances from toys, drones, automatic robots and smart proximity switches. The device can also be used as a simple reflection sensor for hand dryers, towels or soap dispensers, faucets and toilets. Vending machine drop detection; and security and pet doors.
To simplify the design, the TSSP4056 has a PIN photodiode and sensor IC in a compact 6mm x 6.95mm x 5.6mm package. The IR sensor module has a supply voltage range of 2.5V to 5.5V and a typical supply current of 0.7 mA. The sensor is designed to receive IR pulses from a transmitter with a peak wavelength of 940nm. The device is insensitive to supply voltage and ripple noise, shields EMI, and IR filters suppress visible light. The company said that TSSP4056 is RoHS compliant and halogen-free.
