Microchip | MIC3838YMM-TR

The MIC3838YMM TR is a family of complementary output push-pull PWM control ICs that feature high speed and low power consumption. The MIC3838/9 are ideal for telecom level (36 V to 75 V) isolated step down dc/dc conversion applications where high output current, small size, and high efficiency are required

The MIC3838YMM TR is designed for high flexibility with minimum pin-count. The devices are easily configurable for either voltage-mode or current-mode control. Additionally, the MIC3838/9 can easily implement a volt-second clamp that automatically limits the duty cycle during input transients, allowing designers to use the smallest possible transformers and power components. A 3 V reference output is also available that eliminates the need for an external reference. The dual-ended push-pull architecture of the MIC3838/9 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 60 ns to 200 ns, limiting the duty cycle of each output stage to less than 50%. The MIC3838 has a turn-on threshold of 12.5 V whereas the MIC3839 has a lower turn-on threshold of 4.3 V. Both devices are available in a small size MSOP-10 package with an operating range of –40°C to +85°C.

Key Features:

• Dual output drive stages in push-pull configuration.
• Configurable for current-mode or voltage-mode control.
• Easily implements volt-second clamp.
• Leading edge current-sense blanking.
• 3 V reference output available.
• 130 µA typical start-up current.
• 1 mA typical run current.
• Operation to 1 MHz.
• On-chip error amplifier with 4 MHz gain bandwidth product.
• Internal soft start.
• On-chip VDD clamping.
• Output drive stages capable of 500 mA peak source current, 1 A 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.
• 42 V automotive power supplies.
• Base stations.