Rainbow Electronics BA9737KV User Manual

Regulator ICs

4-channel switching regulator
controller

BA9737KV

The BA9737KV is a 4-channel controller that includes all of the circuits required to construct a switching regulator. The
circuits on the chip include a triangular-wave oscillator, a reference voltage circuit, an error amplifier , a PWM comparator,
a pseudo-totem-pole driver, and a short-circuit protection circuit.

Applications
Camcoders and digital still cameras etc.

Features

1) The totem-pole driver can directly drive power tran­sistors, and the on current can be set to the rating cur­rent using an external resistor.
For the off current, the peak current can be set using
an external capacitor.

2) Output cutoff circuit (timer latch type) for overload
protection.

3) Channels 2 and 3 are supplied using the internal ref­erence voltage, and use a positive voltage only.
Channels 1 and 4 are general-purpose channels,
and all inputs are externally available.

4) Channels can be switched off individually or all to­gether (STB and STB1 to STB4).

5) Dead-time control is provided for all channels, and
duty limits can be used.

Absolute maximum ratings (Ta = 25C)

Recommended operating conditions (Ta = 25C)

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Regulator ICs BA9737KV

Block diagram

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