HV746 Datasheet, PDF (1/7 Pages) Supertex, Inc – Dual High Speed ±75V 2.5A Ultrasound Pulser

HV746
Dual High Speed ±75V 2.5A Ultrasound Pulser
Features
► HVCMOS technology for high performance
► High density integration ultrasound transmitter
► 0 to ±75V output voltage
► ±2.5A source and sink current in PW mode
► ±800mA source and sink current in CW mode
► Up to 20MHz operation frequency
► Matched delay times
► 1.2V to 5.0V CMOS logic interface
► Over temperature sensing
► Under voltage protections
► Built-in output drain bleed resistors
Applications
► Portable medical ultrasound imaging
► Piezoelectric transducer drivers
► NDT ultrasound equipment
► Pulse waveform generator
General Description
The Supertex HV746 is a dual-channel monolithic high voltage
high-speed pulse generator. It is designed for portable medical
ultrasound applications. This high voltage and high-speed
integrated circuit can also be used for other piezoelectric,
capacitive or MEMS sensor in ultrasonic nondestructive
detection and sonar ranger applications.
The HV746 consists of controller logic interface circuit, level
translators, MOSFET gate drives and high current power P-
channel and N-channel MOSFETs as the output stage for
each channel. A 2-bit mode control is provided that allows the
maximum output current to be reduced for power saving.
The output stages of each channel are designed to provide
peak output currents over ±3.6A for pulsing, when in mode
4, with up to ±75V swings. When in mode 1, all the output
stages drop the peak current to ±800mA for low-voltage CW
mode operation to save power consumption of the IC. The P
and N type of power FETs gate drivers are supplied by two
floating 9.0VDC power supplies reference to V_PP and V_NN. This
direct coupling topology of the gate drivers not only saves two
high voltage capacitors per channel, but also makes the PCB
layout easier.
Typical Application Circuit
+1.8 to 3.3V +9V
+75V ^{VPP -9V} 0 to +75V
C1
VLL
C2
VDD
C3
C4
VSUB VPF
C5
VPP
+1.8 to 3.3V
Logic
OT P
EN
MC0
MC1
PIN1
NIN1
EN_P WR
Level
Translator
SU B
P-Driver
Level
Translator
N-Driver
RGND
RP1
RN1
TXP1
TXN1
D1
HVOUT1
D2
X1
GREF VSS
1 of 2 Channels
HV746 ^VNF
VNN
C7
C6
VNN +9V
0 to -75V
RGND