Switching Regulator for Chopper Type DC/DC Converter
HA16116FP/FPJ and HA16121FP/FPJ are dual-channel PWM switching regulator controller ICs for use in
chopper-type DC/DC converters.
This IC series incorporates totem pole gate drive circuits to allow direct driving of a power MOS FET. The
output logic is preset for booster, step-down, or inverting control in a DC/DC converter. This logic
assumes use of an N-channel power MOS FET for booster control, and a P-channel power MOS FET for
step-down or inverting control.
HA16116 includes a built-in logic circuit for step-down control only, and one for use in both step-down and
inverting control. HA16121 has a logic circuit for booster control only and one for both step-down and
Both ICs have a pulse-by-pulse current limiter, which limits PWM pulse width per pulse as a means of
protecting against overcurrent, and which uses an on/off timer for intermittent operation. Unlike
conventional methods that use a latch timer for shutdown, when the pulse-by-pulse current limiter
continues operation beyond the time set in the timer, the IC is made to operate intermittently (flickering
operation), resulting in sharp vertical setting characteristics. When the overcurrent condition subsides, the
output is automatically restored to normal.
The dual control circuits in the IC output identical triangle waveforms, for completely synchronous
configuring a compact, high efficiency dual-channel DC/DC converter, with fewer external components
than were necessary previously.
• 2.5 V reference voltage (Vref) regulator
• Triangle wave form oscillator
• Dual overcurrent detector
• Dual totem pole output driver
• UVL (under voltage lock out) system
• Dual error amplifier
• Vref overvoltage detector
• Dual PWM comparator
Rev.2.0, Sep.18.2003, page 1 of 33