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BLOCK DIAGRAM

•

Receives Both Power and Signal Across

the Isolation Boundary

•

9 to 15 Volt High Level Gate Drive

•

Under-voltage Lockout

•

Programmable Over-current Shutdown

and Restart

•

Output Enable Function

The UC1725 and its companion chip, the UC1724, provide all the nec-

essary features to drive an isolated MOSFET transistor from a TTL in-

put signal. A unique modulation scheme is used to transmit both power

and signals across an isolation boundary with a minimum of external

components.

Protection circuitry, including under-voltage lockout, over-current shut-

down, and gate voltage clamping provide fault protection for the MOS-

FET. High level gate drive is guaranteed to be greater than 9 volts and

less than 15 volts under all conditions.

Uses include isolated off-line full bridge and half bridge drives for driv-

ing motors, switches, and any other load requiring full electrical isola-

tion.

The UC1725 is characterized for operation over the full military tem-

perature range of -55°C to +125°C while the UC2725 and UC3725 are

characterized for -25°C to +85°C and 0°C to +70°C respectively.

UC1725

UC2725

UC3725

Isolated High Side FET Driver

FEATURES

DESCRIPTION

UDG-92051-1