PWM CONTROL 3A STEP-DOWN CONVERTER
DESCRIPTION
UTC P1886 consists of 3A step-down switching regulator
control which includes a reference voltage source, oscillation
circuit, error amplifier, internal PMOS and etc with PWM.
UTC P1886 can provide low-ripple power, high efficiency, and
excellent transient characteristics and an enable function, an over
current protect function and a short circuit protect function are built
inside, so the operation frequency will be reduced from 300KHz to
30KHz when OCP or SCP happens. And the PWM control circuit
can vary the duty ratio linearly from 100 down to 0%. This
converter also includes an error amplifier circuit as well as a
soft-start circuit that prevents overshoot at startup. Also, to
minimum external component count an internal compensation
block is built in.
UTC P1886 can work as step-down switching regulators with
the addition of an internal P-channel Power MOS, a coil,
capacitors, and a diode connected externally. It provides such
outstanding features: low current consumption. It is also suitable
for the operation via an AC adapter because this converter can accommodate an input voltage up to 23V.
FEATURES
* Soft-start, Current Limit, Enable function
* Thermal Shutdown function
* Built-in internal SW P-channel MOS
* Input voltage: 4V to 23V.
* Output voltage: 0.8V to VCC.
* Duty ratio: 0% to 100% PWM control
* Oscillation frequency: 300KHz typ.
TYPICAL APPLICATION CIRCUIT
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