The PM8804 is a PWM controller that integrates all the circuitry required to design a smart and efficient 48 V converter for PoE and telecom mid-power applications.
It features a programmable oscillator for the switching frequency, adjustable slope compensation, dual complementary low-side drivers with programmable dead time, programmable soft-start, soft turn off and a programmable current sense blanking time.
An internal high-voltage linear regulator with a typical 20 mA output current allows the device to start up with a minimum of external components.
Complementary 1 A peak gate drivers make possible to implement high power topologies, while when the second drives is not used, like with simple low power flyback converters, it can be turned off.
The device embeds a set of protections that enables the design of a self-protected converter with the scope to eliminate the risk of catastrophic failure at system level.
The device targets high efficiency conversion at wide range of load.
- PWM peak current mode controller
- Input operating voltage up to 75 V
- Internal high-voltage start up regulator with 20 mA current capability
- Current sense with programmable blanking time up to 200 ns
- Programmable fixed frequency up to 1 MHz
- Soft-start up with settable time
- Soft turn off (optionally disabled)
- Dual low-side complementary gate drivers
- Programmable dead time from 10 to 200 ns between GATE1 and GATE2
- Gate drivers have 1 A peak capability
- GATE2 optionally turned off for reduced consumption
- 80% maximum duty cycle with internal slope compensation
- Internal pull-up resistor on CTL pin enables the optocoupler connection
- Operating current consumption < 1.5 mA
- Embedded protections:
- Severe overcurrent protection with latch after 4 events
- Delayed overload protection with automatic restart
- Feedback disconnection (OV) protection on VC
- Thermal shutdown
- High efficiency topologies:
- Flyback, forward
- Flyback with synchronous rectification
- Flyback with active clamp
- Forward with active clamp
(**) The Material Declaration forms available on st.com may be generic documents based on the most commonly used package within a package family. For this reason, they may not be 100% accurate for a specific device. Please contact our sales support for information on specific devices.