General Description nThe 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. nThe 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%.nFeatures n• Dual output drive stages in push-pull configuration n• Leading edge current-sense blanking n• 130µA typical start-up current n• 1mA typical run current n• Operation to 1MHz n• Internal soft start n• On-chip error amplifier with 4MHz gain bandwidth product n• On-chip VDD clamping n• Output drive stages capable of 500mA peak source current, 1A peak sink current n nApplications n• High efficiency “brick” power supply modules n• Half bridge converters n• Full bridge converters n• Push-pull converters n• Voltage-fed push-pull converters n• Telecom equipment and power supplies n• Networking power supplies n• Industrial power supplies n• 42V automotive power supplies n• Base stations
