1 Features

• Fully integrated solution for ultrasonic sensing

• Complimentary low-side drivers with configurable

current limit supporting both transformer based

and direct drive topology for transducer excitation

• Single transducer for both burst/listen or a

transducer pair, one for burst and the other for

listen operation

• Low-noise receiver with programmable 6-point

time-varying gain (32 to 90 dB) with DSP (BPF,

demodulation) for echo envelope detection

• Two presets of 12-point time-varying threshold for

object detection

• Timers to measure multiple echo distance and

duration

• Integrated temperature sensor

• Record time for object detection up to 11 m

• 128 bytes of RAM for echo recording

• 42 bytes of user EEPROM to store configuration

for fast initialization

• One-wire high-voltage time-command interface or

USART asynchronous interface

• CMOS level USART interface

• Sensor diagnostics (decay frequency and time,

excitation voltage), supply, and transceiver

diagnostics

2 Applications

• Ultrasonic radar

• Object distance and position sensing

• Presence and proximity detection

• Drone and robotics landing assist and obstacle

detection

• Occupancy and motion sensors

3 Description

The PGA460 device is a highly-integrated system

on-chip ultrasonic transducer driver and signal

conditioner with an advanced DSP core. The device

has a complimentary low-side driver pair that can

drive a transducer either in a transformer based

topology using a step-up transformer or in a directdrive

topology using external high-side FETs. The

device can receive and condition the reflected echo

signal for reliable object detection. This feature

is accomplished using an analog front-end (AFE)

consisting of a low-noise amplifier followed by a

programmable time-varying gain stage feeding into an

ADC. The digitized signal is processed in the DSP

core for both near-field and far-field object detection

using time-varying thresholds.

The main communication with an external controller is

achieved by either a time-command interface (TCI) or

a one-wire USART asynchronous interface on the IO

pin, or a CMOS-level USART interface on the RXD

and TXD pins. The PGA460 can be put in ultra-low

quiescent current low-power mode to reduce power

consumption when not in use and can be woken up

by commands on the communication interfaces.

The PGA460 also includes on-chip system

diagnostics which monitor transducer voltage during

burst, frequency and decay time of transducer

to provide information about the integrity of the

excitation as well as supply-side and transceiver-side

diagnostics for overvoltage, undervoltage, overcurrent

and short-circuit scenarios.