HIP4080A/81AEVALZ Просмотр технического описания (PDF) - Intersil

Номер в каталоге

Компоненты Описание

производитель

HIP4080A/81AEVALZ

HIP4080A, 80V High Frequency H-Bridge Driver

Intersil 

®

Application Note

HIP4080A, 80V High Frequency

H-Bridge Driver

December 11, 2007

AN9404.3

Author: George E. Danz

Introduction

The HIP4080A is a member of the HIP408x family of High

Frequency H-Bridge Driver ICs. A simplified application

diagram of the HIP4080A IC is shown in Figure 1. The

HIP408x family of H-Bridge driver ICs provide the ability to

operate from 10VDC to 80VDC busses for driving H-Bridges,

whose switch elements are comprised of power N-Channel

MOSFETs. The HIP408X family, packaged in both 20 Ld DIP

and 20 Ld SOIC DIPs, provide peak gate current drive of

2.5A. The HIP4080A includes undervoltage protection,

which sends a continuous gate turn-off pulse to all gate

outputs when the VDD voltage falls below a nominal 8.25V.

The startup sequence of the HIP4080A is initiated when the

VDD voltage returns above a nominal 8.75V. Of course, the

DIS pin must be in the low state for the IC to be enabled. The

startup sequence turns on both low side outputs, ALO and

BLO, so that the bootstrap capacitors for both sides of the

H-bridge can be fully charged. During this time the AHO and

BHO gate outputs are held low continuously to insure that no

shoot-through can occur during the nominal 400ns boot-strap

refresh period. At the end of the boot strap refresh period the

outputs respond normally to the state of the input control

signals.

A combination of bootstrap and charge-pumping techniques

is used to power the circuitry which drives the upper halves

of the H-Bridge. The bootstrap technique supplies the high

instantaneous current needed for turning on the power

devices, while the charge pump provides enough current to

“maintain” bias voltage on the upper driver sections and

MOSFETs. Since voltages on the upper bias supply pin

“float” along with the source terminals of the upper power

switches, the design of this family provides voltage capability

for the upper bias supply terminals to 95VDC.

The HIP4080A can drive lamp loads for automotive and

industrial applications as shown in Figure 2. When inductive

loads are switched, flyback diodes must be placed around

the loads to protect the MOSFET switches.

Many applications utilize the full bridge topology. These are

voice coil motor drives, stepper and DC brush motors, audio

amplifiers and even power supply inverters used in

uninterruptable power supplies, just to name a few. Of the

above, voice coil motor drives and audio amplifiers can take

advantage of the built-in comparator available in the

HIP4080A. Using the output of the comparator to add some

positive feedback, a hysteresis control, so popular with voice

coil motor drivers, can be implemented as shown in Figure 1.

In the figure, R3 is fed back from the comparator output,

OUT, to the positive input of the comparator, IN+. Capacitor,

C1, integrates in a direction to satisfy the reference current

signal at IN. The IN- input of the comparator sums this

current reference with a signal proportional to load current

through resistor, R4, which comes from a differential

amplifier, A1. A bias voltage of 6V (represents half of the

bias voltage and the maximum rail to rail voltage of the

comparator and amplifier, A1) biases the comparator’s IN+

terminal through R2 and the amplifier, A1’s, positive

summing junction.

80V

12V

HIP4080A

GND

GND

FIGURE 1. HIP4080A SIMPLIFIED APPLICATION

DIAGRAM

+80V

HIP408x

GND

FIGURE 2. HIP4080A AS LAMP SWITCH DRIVER, DUAL

HIGH/LOW SWITCHES FOR AUTOMOTIVE AND

INDUSTRIAL CONTROLS

1

CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.

1-888-INTERSIL or 1-888-468-3774 | Intersil (and design) is a registered trademark of Intersil Americas Inc.

Copyright © Intersil Americas Inc. 2007. All Rights Reserved

All other trademarks mentioned are the property of their respective owners.

Share Link: