LM5115

PRELIMINARY www.DataSheet4U.com March 2005 LM5115 Secondary Side Post Regulator Controller LM5115 Secondary Side Post Regulator Controller General Description The LM5115 controller contains all of the features necessary to implement multiple output power converters utilizing the Secondary Side Post Regulation (SSPR) technique. The SSPR technique develops a highly efficient and well regulated auxiliary output from the secondary side switching waveform of an isolated power converter. Regulation of the auxiliary output voltage is achieved by leading edge pulse width modulation (PWM) of the main channel duty cycle. Leading edge modulation is compatible with either current mode or voltage mode control of the main output. The LM5115 drives external high side and low side NMOS power switches configured as a synchronous buck regulator. A current sense amplifier provides overload protection and operates over a wide common mode input range. Additional features include a low dropout (LDO) bias regulator, error amplifier, precision reference, adaptive dead time control of the gate signals and thermal shutdown. Features n n n n n n n n n n n n n Self-synchronization to main channel output Free-run mode for buck regulation of DC input Leading edge pulse width modulation Voltage-mode control with current injection and input line feed-forward Operates from AC or DC input up to 75V Wide 4.5V to 30V bias supply range Wide 0.75V to 12V output range. Top and bottom gate drivers sink 2.5A peak...