Preliminary data

This is preliminary information on a new product now in development or undergoing evaluation. Details are subject to

change without notice.

January 2010

Doc ID 15450 Rev 1

1/22

22

STHV748

5-level, ±90 V, 2 A high-speed pulser

with four independent channels

Features

channel in pulse wave (PW) mode

– 5-level output waveform

– ±2 A source and sink current

– Down to 20 ps jitter

– Anti-cross conduction function

– Low 2nd harmonic distortion

– Fine-tuning on propagation delay

–6

Ω synchronous active clamp

– Anti-leakage on output node

(CW) mode on each

– Down to 0.1 W power consumption

– ±0.6 A source and sink current

– Down to 10 ps jitter

– 13.5

Ω on resistance

– HV MOS topology to minimize current

consumption

– Up to 300 MHz BW

– Noise blocking diodes

– Fully self-biaising architecture

– Anti-memory effect for all internal HV

nodes

– Thermal protection

– Stand by function

Applications

Description

This monolithic, high-voltage, high-speed pulser

generator features four independent channels. It

is designed for medical ultrasound applications,

but can also be used for other piezoelectric,

capacitive or MEMS transducers. The device

comprises a controller logic interface circuit, level

translators, MOSFET gate drivers, noise blocking

diodes and high-power P-channel and N-channel

MOSFETs as output stage for each channel,

clamping-to-ground circuitry, anti-leakage, anti-

memory effect block, thermal sensor and HV

receiver switch (HVR_SW) which guarantees a

strong decoupling during transmission phase.

Moreover the STHV748 includes self biasing and

thermal shutdown blocks (see Figure 1).

Each channel can support up to five active output

levels with two half bridges. The output stage of

each channel is able to provide ±2 A peak output

current. In order to reduce power dissipation

during continuous wave mode, the peak current is

limited to 0.6 A (a dedicated half bridge is used).

Table 1.

Device summary

Order code

Package

Packaging

STHV748QTR

QFN64

Tape and reel

QFN64 9 x 9 x1.0 mm

www.st.com