SI9978DW Datasheet, PDF (1/6 Pages) Vishay Siliconix – Configurable H-Bridge Driver

Configurable H-Bridge Driver
Si9978DW
Vishay Siliconix
Si9978
FEATURES
• H-Bridge or Dual Half-Bridge Operation • Cross-Conduction Protected
• 20- to 40-V Supply
• Current Limit
• Static (dc) Operation
• Undervoltage Lockout
• ESD Protected
• Fault Output
DESCRIPTION
The Si9978DW is an integrated driver for an n-channel
MOSFET H-bridge. The mode control allows operation as
either a full H-bridge driver or as two independent
half-bridges. The DIR/PWM input configuration allows easy
implementation of either sign/magnitude or anti-phase PWM
drive schemes for full H-bridges. Schmitt triggers on the
inputs provide logic signal compatibility and hysteresis for
increased noise immunity. An internal low-voltage regulator
allows the device to be powered directly from a system supply
of 20 to 40 volts. All n-channel gates are driven directly from
low-impedance outputs. The addition of one external
capacitor per half-bridge allows internal circuitry to level shift
both the power supply and logic signal for the high-side
n-channel gate drives. Internal charge pumps replace leakage
current lost in the high-side driver circuits to provide “static”
(dc) operation in any output condition. Protection features
include an undervoltage lockout, cross-conduction prevention
logic, and overcurrent monitors.
The Si9978DW is available in the 24-pin wide-body SOIC
(surface mount) package, specified to operate over the
industrial (-40 to +85°C) temperature range.
FUNCTIONAL BLOCK DIAGRAM
FaxBack 408-970-5600, request 70011
www.siliconix.com
S-60752—Rev. D, 05-Apr-99
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