OB3375x

GENERAL DESCRIPTION

The OB3375X is a high efficiency LED power switch designed for white LEDS and for large LCDS backlight. OB3375X is built-in a quasi-resonant control method buck DC/DC converter. The controller implements a peak current mode control scheme and an internal transconductance amplifier to accurately control the output current over a wide input and load conditions. The transconductance amplifier reference is set by internal reference voltage and the duty cycle at HPWM pin. Low frequency LPWM dimming input that can accept an external control signal with a duty ratio of 1%-100%.

OB3375X offers comprehensive protection features to protect the system in various fault conditions such as Diode & Inductor short protection, CS open protection, Drain/CSshort protection, LED+/LED- short protection,LED-/GND short circuit protection, LED open loop protection, Over temperature protection (OTP). The cycle-by-cycle current limit function limits the maximum current flowing through the internal MOSFET.

OB3375X is offered in SOP8 package.


FEATURES

nLow system cost and high efficiency

nQuasi-Resonant buck topology operation

nProgrammable CC regulation

nPWM and PWM to analog combination dimming

nZero voltage signal detected to improve efficiency and EMI performance

nLED+/LED- short circuit protection

nLED-/GND short circuit protection

nLED open loop protection

nCycle-by-cycle current limiting

nBuilt-in leading edge blanking (LEB)

nVIN under voltage lockout with hysteresis

nOver temperature protection (OTP)

nDiode & Inductor short protection

nDrain/CSshort protection

nCS open protection

nLow standby current

APPLICATIONS

nLED backlight


TYPICAL APPLICATION

Baidu
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