Texas Instruments TL851 Sonar Ranging Control TL851CDG4

The TL851 Sonar Ranging Control is a digital I2L integrated circuit designed for use with the TL852 sonar ranging receiver. It facilitates distance measurement from six inches to 35 feet and operates with a single supply voltage ranging from 4.5 V to 6.8 V. The device features an internal oscillator that requires a low-cost external ceramic resonator, specifically a 420-kHz unit, to drive a 50-kHz electrostatic transducer. The TL851 initiates its cycle upon receiving a high logic level signal on the INIT pin, transmitting a burst of 16 pulses. It includes an internal blanking feature that disables the receive input for 3.8 ms after initiation to prevent false readings from transducer ringing and echoes from nearby objects. The device also provides a synchronous 4-bit gain control output for the TL852, allowing for 12 steps of gain adjustment. Characterized for operation in temperatures from 0°C to 40°C, the TL851 is TTL-compatible and interfaces with both electrostatic and piezoelectric transducers. Its internal receive level detector has a threshold of 1.2 V, making it suitable for various sonar applications.