MIC3809 Datasheet | Micrel Semiconductor

Description The MIC3808 and MIC3809 are a family of plementary output push-pull PWM control ICs that feature high speed and low power consumption. The MIC3808/9 are ideal for tele 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 singleended 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 ponents. 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%. The MIC3808/9 are built on a low-power, high-speed Bi CMOS process. The 130µA start-up current and 1m A run-current reduce the size of the start-up circuitry and allow high efficiency even at light loads. The high-speed internal 4MHz error amplifier allows MIC3808/9 operation up to 1MHz. The MIC3808 has a turn-on threshold of 12.5V whereas the MIC3809 has a lower turn-on threshold of 4.3V. Both devices are available in SOP-8 and MSOP-8 package options with an operating range of - 40°C to +85°C. Data sheets and support documentation can be found on Micrel’s web site at: .micrel.. Features - - - - - - - Dual output drive stages in push-pull configuration Leading edge current-sense blanking 130µA typical start-up current 1m A 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 500m A 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 - Tele equipment and power supplies - Networking power supplies - Industrial power...