General Description

The MIC3808 and MIC3809 are a family of complementary output push-pull PWM control ICs that feature high speed and low power consumption. The MIC3808/9 are ideal for telecom level (36V to 75V) isolated step down dc/dc conversion applications where high output current, small size, and high efficiency are required.

The dual-ended push-pull architecture of the MIC3808/9 allows more efficient utilization of the transformer than single ended topologies, allowing smaller size dc/dc solutions. Additionally, the out-of-phase push-pull topology allows a higher effective duty cycle, reducing input and output ripple as well as stress on the external components. The dead-time between the two outputs is adjustable between 60ns to 200ns, limiting the duty cycle of each output stage to less than 50.

特性 Features

? Dual output drive stages in push-pull configuration

? Leading edge current-sense blanking

? 130μA typical start-up current

? 1mA typical run current

? Operation to 1MHz

? Internal soft start

? On-chip error amplifier with 4MHz gain bandwidth product

? On-chip VDD clamping

? Output drive stages capable of 500mA peak source current, 1A peak sink current

Applications

? High efficiency “brick” power supply modules

? Half bridge converters

? Full bridge converters

? Push-pull converters

? Voltage-fed push-pull converters

? Telecom equipment and power supplies

? Networking power supplies

? Industrial power supplies

? 42V automotive power supplies

? Base stations