LM25149 Series

42-V synchronous buck DC/DC controller with ultra-low IQ and integrated active EMI filter

Catalog

42-V synchronous buck DC/DC controller with ultra-low IQ and integrated active EMI filter

Part	Outputs and Type	Outputs and Type	Frequency - Switching	Voltage - Input [Min]	Voltage - Input [Max]	Supplied Contents	Regulator Topology	Board Type	Voltage - Output	Utilized IC / Part	Main Purpose	Current - Output	Frequency - Switching [Min]	Frequency - Switching [Max]	Output Phases	Mounting Type	Supplier Device Package [y]	Supplier Device Package	Supplier Device Package [x]	Control Features	Voltage - Supply (Vcc/Vdd) [Max]	Voltage - Supply (Vcc/Vdd) [Min]	Synchronous Rectifier	Topology	Operating Temperature [Max]	Operating Temperature [Min]	Duty Cycle (Max) [Max]	Number of Outputs	Function	Clock Sync	Output Type	Output Configuration	Package / Case
Texas Instruments LM25149-Q1EVM-2100	Non-Isolated	1	2.1 MHz	3.5 V	42 V	Board(s)	Buck	Fully Populated	5 V	LM25149-Q1	DC/DC Step Down	8 A
Texas Instruments LM25149RGYR													100 kHz	2.2 MHz	1	Surface Mount	3.5	24-VQFN	5.5	Current Limit Enable Frequency Control Power Good Ramp Soft Start Sync	42 V	3.5 V		Buck	150 °C	-40 °C	100 %	1	Step-Down		Transistor Driver	Positive	24-VFQFN Exposed Pad

Catalog

42-V synchronous buck DC/DC controller with ultra-low IQ and integrated active EMI filter

Key Features

• Functional Safety-CapableDocumentation available to aid functional safety system designTwo integrated EMI mitigation mechanismsActive EMI Filter for enhanced EMI performance at lower frequenciesSelectable dual random spread spectrum (DRSS) for enhanced EMI performance across low and high-frequency bandsEMI reduced by an average of 25 dBµVReduces the external differential-mode input filter size by 50% and lowers systems costOptimized for CISPR 32 Class B requirementsVersatile synchronous buck DC/DC controllerWide input voltage range of 3.5 V to 42 V1% accurate, fixed 3.3-V, 5-V, 12-V, or adjustable output from 0.8 V to 36 V150°C maximum junction temperatureShutdown mode current: 2.3 µANo-load sleep current: 9.5 µAStackable up to two phasesAdvanced dropout with frequency foldbackSwitching frequency from 100 kHz to 2.2 MHzSYNC in and SYNC out capabilityInherent protection features for robust designInternal hiccup-mode overcurrent protectionENABLE and PGOOD functionsVCC, VDDA, and gate-drive UVLO protectionInternal or external loop compensationThermal shutdown protection with hysteresisCreate a custom design using the LM25149 withWEBENCH Power DesignerFunctional Safety-CapableDocumentation available to aid functional safety system designTwo integrated EMI mitigation mechanismsActive EMI Filter for enhanced EMI performance at lower frequenciesSelectable dual random spread spectrum (DRSS) for enhanced EMI performance across low and high-frequency bandsEMI reduced by an average of 25 dBµVReduces the external differential-mode input filter size by 50% and lowers systems costOptimized for CISPR 32 Class B requirementsVersatile synchronous buck DC/DC controllerWide input voltage range of 3.5 V to 42 V1% accurate, fixed 3.3-V, 5-V, 12-V, or adjustable output from 0.8 V to 36 V150°C maximum junction temperatureShutdown mode current: 2.3 µANo-load sleep current: 9.5 µAStackable up to two phasesAdvanced dropout with frequency foldbackSwitching frequency from 100 kHz to 2.2 MHzSYNC in and SYNC out capabilityInherent protection features for robust designInternal hiccup-mode overcurrent protectionENABLE and PGOOD functionsVCC, VDDA, and gate-drive UVLO protectionInternal or external loop compensationThermal shutdown protection with hysteresisCreate a custom design using the LM25149 withWEBENCH Power Designer

Description

The LM25149 is a 42-V, ultra-low IQsynchronous buck DC/DC controller for high-current, single-output applications. The controller uses a peak current-mode control architecture for easy loop compensation, fast transient response, and excellent load and line regulation. The LM25149 can be set up in interleaved dual-phase mode with accurate current sharing for high-current applications. It can operate with VINas low as 3.5 V, at nearly 100% duty cycle if needed. The LM25149 has two unique EMI reduction features: active EMI filter and dual random spread spectrum (DRSS). The active EMI filter senses any noise or ripple voltage on the DC input bus and injects an out-of-phase cancellation signal to reduce the disturbance. DRSS combines low-frequency triangular and high-frequency randomized modulations to mitigate EMI across lower and higher frequency bands, respectively. This hybrid technique aligns with the multiple resolution bandwidth (RBW) settings specified in industry-standard EMC tests. Additional features of the LM25149 include 150°C maximum junction temperature operation, user-selectable diode emulation for lower current consumption at light-load conditions, open-drain power-good flag for fault reporting and output monitoring, precision enable input, monotonic start-up into prebiased load, integrated VCC bias supply regulator and bootstrap diode, internal 3-ms soft-start time, and thermal shutdown protection with automatic recovery. The LM25149 controller comes in a 3.5-mm × 5.5-mm thermally enhanced, 24-pin VQFN package with an exposed pad to aid in thermal dissapation. The LM25149 is a 42-V, ultra-low IQsynchronous buck DC/DC controller for high-current, single-output applications. The controller uses a peak current-mode control architecture for easy loop compensation, fast transient response, and excellent load and line regulation. The LM25149 can be set up in interleaved dual-phase mode with accurate current sharing for high-current applications. It can operate with VINas low as 3.5 V, at nearly 100% duty cycle if needed. The LM25149 has two unique EMI reduction features: active EMI filter and dual random spread spectrum (DRSS). The active EMI filter senses any noise or ripple voltage on the DC input bus and injects an out-of-phase cancellation signal to reduce the disturbance. DRSS combines low-frequency triangular and high-frequency randomized modulations to mitigate EMI across lower and higher frequency bands, respectively. This hybrid technique aligns with the multiple resolution bandwidth (RBW) settings specified in industry-standard EMC tests. Additional features of the LM25149 include 150°C maximum junction temperature operation, user-selectable diode emulation for lower current consumption at light-load conditions, open-drain power-good flag for fault reporting and output monitoring, precision enable input, monotonic start-up into prebiased load, integrated VCC bias supply regulator and bootstrap diode, internal 3-ms soft-start time, and thermal shutdown protection with automatic recovery. The LM25149 controller comes in a 3.5-mm × 5.5-mm thermally enhanced, 24-pin VQFN package with an exposed pad to aid in thermal dissapation.