General Description

CM6901 is a SLS, SRC/LLC + SR resonant controller and it can operate at both SRC and LLC region with synchronous rectification to achieve high efficiency. Its unique features: FM + 2 PWMING modes. It is used for DC-DC conversion in offline application. Light load regulation is accomplished by transitioning the controller from frequency modulation mode into PWM mode. To have the optimal balance performance between hold-up time and efficiency, its frequency range crosses fr1, resonant frequency.

CM6901 system has a constant voltage feedback loop with precision 2.5V Vfb reference. The 1V ILIMIT can be latched when a standby converter is applied; otherwise, it is an auto-restart I limit.

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Features

Inrush Current Control
Separated PFC OVP pin
Separated Power VCC and Analog VCC
Separated Power Ground and Analog Ground
Additional folded-back current limit for PWM section.
23V Bi-CMOS process
VIN OK guaranteed turn on PWM at 2.5V instead of 1.5V
Internally synchronized leading edge PFC and trailing edge PWM in one IC
Slew rate enhanced transconductance error amplifier for ultra-fast PFC response
Low start-up current (100μA typ.)
Low operating current (3.0mA type.)
Low total harmonic distortion, high PF
Reduces ripple current in the storage capacitor between the PFC and PWM sections
Average current, continuous or discontinuous boost leading edge PFC
VCC OVP Comparator
Low Power Detect Comparatoru PWM configurable for current mode or voltage mode operation
Current fed gain modulator for improved noise immunity
Brown-out control, over-voltage protection, UVLO, and soft start, and Reference OK

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Applications

u DC-DC power supply.

u Operates in FM/PWM mode.

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Packages

16-Pin PDIP
16-Pin SOIC