The Supertex MD1715, paired with the Supertex TC8020, forms a two channel, five level, high voltage, high speed transmit pulser chip set. The chip set is designed for medical ultrasound imaging applications, but can also be used for metal flaw detection, nondestructive evaluation, and piezoelectric transducer drivers.

 

The MD1715 is a two channel logic controller circuit with 12 low impedance MOSFET gate drivers. There are two sets of control logic inputs, one each for channels A and B. Each channel consists of three pairs of MOSFET gate drivers. These drivers are designed to match the drive requirements of the Supertex TC8020.

 

The TC8020 is the output stage of the pulser, with six pairs of MOSFETs. Each pair consists of a P-channel and an N-channel MOSFET. They are designed to have the same impedance and can provide typical peak currents of ±3.5 amps at 200V.

 

MD1715主要特性：

 

Advanced CMOS technology

 

±4.5 to 12.5V power supply voltage

 

2A output source and sink current

 

6.5ns rise and fall time with 1nF load

 

10ns propagation delay

 

±2ns matched delay times

 

12 matched channels

 

1.8V to 3.3V CMOS logic interface

 

Smart logic threshold

 

Low inductance package

 

MD1715應(yīng)用：

 

Medical ultrasound imaging

 

Piezoelectric transducer drivers

 

Metal flaw detection

 

Nondestructive evaluation

 

The Supertex TC8020 consists of six pairs of high voltage, low threshold N- and P-channel MOSFETs in a 56-lead QFN package.

 

All MOSFETs have integrated gate-to-source resistors and gateto-source Zener diode clamps which are desired for high voltage pulser applications. The complimentary, high-speed, high voltage, gate-clamped N- and P-channel MOSFET pairs utilize an advanced vertical DMOS structure and Supertex’s well-proven silicon-gate manufacturing process. This combination produces a device with the power handling capabilities of bipolar transistors and with the high input impedance and positive temperature coefficient inherent in MOS devices.

 

Characteristic of all MOS structures, this device is free from thermal runaway and thermally-induced secondary breakdown. Supertex’s vertical DMOS FETs are ideally suited to a wide range of switching and amplifying applications where very low threshold voltage, high breakdown voltage, high input impedance, low input and output capacitance, and fast switching speeds are desired.

 

TC8020主要特性：

 

High voltage, vertical DMOS technology

 

Integrated gate-to-source resistor

 

Integrated gate-to-source Zener diode

 

Typical peak output +/-3.5A at 50V

 

Low threshold, low on-resistance

 

Low input & output capacitance

 

Fast switching speeds

 

Electrically isolated N- and P-MOSFET pairs

 

TC8020應(yīng)用：

 

High voltage pulsers

 

Amplifiers

 

Buffers

 

Piezoelectric transducer drivers

 

General purpose line drivers

 

Logic level interfaces

 

圖1MD1715和TC8020典型應(yīng)用電路

 

圖2MD1715和TC8020引腳布局圖

圖3MD1715和TC8020詳細電路圖