HV739DB1 Datasheet, PDF (1/8 Pages) Supertex, Inc – HV739 ±100V 3.0A Ultrasound Pulser Demo Board

HV739DB1
HV739 ±100V 3.0A Ultrasound Pulser Demo Board
Introduction
The HV739 is a monolithic single channel, high-speed, high
voltage, ultrasound transmitter pulser. This integrated, high
performance circuit is in a single, 5x5mm, 32-lead QFN
package.
The HV739 can deliver up to a ±3.0A source and sink current
to a capacitive transducer. It is designed for the ultrasound
material inspection NDT and medical ultrasound imaging
applications. It can also be used as a high voltage driver
for other piezoelectric or capacitive MEMS transducers, or
for ATE systems and pulse signal generators as a signal
source.
HV739’s circuitry consists of controller logic circuits, level
translators, gate driving buffers and a high current and high
voltage MOSFET output stage. The output stages of each
channel are designed to provide peak output currents over
±3.0A for pulsing, with up to ±100 volt swings. Two float-
ing 12VDC power supplies referenced to V_PP and V_NN supply
the P- and N-type power FET gate drivers. The upper limit
frequency of the pulser waveform is 35MHz depending on
the load capacitance. The HV739 can also be used as a
damping circuit to generate fast return-to-zero waveforms
by working with another HV739 as a pulsing circuit. It also
has built-in under-voltage and over-temperature protection
functions.
Designing a Pulser with the HV739
This demo board data sheet describes how to use the
HV739DB1 to generate the basic high voltage pulse wave-
form as an ultrasound transmitting pulser.
The HV739 circuit uses the DC coupling method in all level
translators. There are no external coupling capacitors need-
ed. The V_PP and V_NN rail voltages can be changed rather
quickly, compared to a high voltage capacitor gate-coupled
driving pulser. This direct coupling topology of the gate driv-
ers not only saves two high voltage capacitors per channel,
but also makes the PCB layout easier.
The input stage of the HV739 has high-speed level transla-
tors that are able to operate with logic signals of 1.8 to 5.0V
volts and are optimized at 3.3 to 5.0V. In this demo board,
the control logic signals are connected to a high-speed rib-
bon cable connector. The control signal logic-high voltage
should be the same as the V_CC voltage of the demo board,
and the logic-low should be reference to GND.
The HV739DB1 output waveforms can be displayed using
an oscilloscope directly by connecting the scope probe to
the test point HV_OUT and GND. The soldering jumper can se-
lect whether or not to connect the on-board equivalent-load,
a 330pF, 200V capacitor, parallel with a 2.5kΩ, 1W resistor.
A coaxial cable can be used to connect the user’s transducer
to easily drive and evaluate the HV739 transmitter pulser.
Application Circuit
+3.3V +12V
+100V (V_PP-12V) 0 to +100V
V_CC
OTP
EN
Logic PIN1
Control
NIN1
GREF
V_LL
V_DD
V_SUB V_PF
V_PP
Level
Translator
P-Driver
HV739
Level
Translator
N-Driver
RGND
TXP
TXN
V_SS
GND
RGND
V_NF
V_NN
(V_NN+ 12V) 0 to -100V
HV_OUT
GND