LM5041A Series

The LM5041B PWM controller contains all of the features necessary to implement either current-fed or voltage-fed push-pull or bridge power converters. These "Cascaded" topologies are well suited for multiple output and higher power applications. The LM5041B includes these four control outputs: the buck stage controls (HD and LD) and the push-pull control outputs (PUSH and PULL). Push-pull outputs are driven at 50% nominal duty cycle at one half of the switching frequency of the buck stage and can be configured for either a guaranteed overlap time (for current-fed applications) or a guaranteed non-overlap time (for voltage-fed applications). Push-pull stageMOSFETscan be driven directly from the internal gate drivers while the buck stage requires an external driver such as the LM5102. The LM5041B includes a high-voltage start-up regulator that operates over a wide input range of 15V to 100V. The PWM controller is designed for high-speed capability including an oscillator frequency range up to 1 MHz and total propagation delays of less than 100 ns. Additional features include line Under-Voltage Lock-Out(UVLO), Soft-Start, an error amplifier, precision voltage reference, and thermal shutdown. The differences between LM5041, LM5041A and LM5041B are as follows: In the LM5041A and the LM5041B version, the hiccup mode over-current protection is not employed and the VCC bias regulator is not disabled by a low state at the SS pin. In the LM5041B version, both the high and low side buck stage gate drivers are forced to a low state when the controller is disabled. In the LM5041 and the LM5041B version, the buck stage controller is disabled by either a low state at theUVLOpin or a low state at the SS pin. Also in the LM5041B version, the REF pin 5V regulator is not disabled by aUVLOpin low state. The LM5041B PWM controller contains all of the features necessary to implement either current-fed or voltage-fed push-pull or bridge power converters. These "Cascaded" topologies are well suited for multiple output and higher power applications. The LM5041B includes these four control outputs: the buck stage controls (HD and LD) and the push-pull control outputs (PUSH and PULL). Push-pull outputs are driven at 50% nominal duty cycle at one half of the switching frequency of the buck stage and can be configured for either a guaranteed overlap time (for current-fed applications) or a guaranteed non-overlap time (for voltage-fed applications). Push-pull stageMOSFETscan be driven directly from the internal gate drivers while the buck stage requires an external driver such as the LM5102. The LM5041B includes a high-voltage start-up regulator that operates over a wide input range of 15V to 100V. The PWM controller is designed for high-speed capability including an oscillator frequency range up to 1 MHz and total propagation delays of less than 100 ns. Additional features include line Under-Voltage Lock-Out(UVLO), Soft-Start, an error amplifier, precision voltage reference, and thermal shutdown. The differences between LM5041, LM5041A and LM5041B are as follows: In the LM5041A and the LM5041B version, the hiccup mode over-current protection is not employed and the VCC bias regulator is not disabled by a low state at the SS pin. In the LM5041B version, both the high and low side buck stage gate drivers are forced to a low state when the controller is disabled. In the LM5041 and the LM5041B version, the buck stage controller is disabled by either a low state at theUVLOpin or a low state at the SS pin. Also in the LM5041B version, the REF pin 5V regulator is not disabled by aUVLOpin low state.