link to page 32 EVALUATION KIT AVAILABLE Click here for production status of specific part numbers. MAX25601A/MAX25601B/Synchronous Boost andMAX25601C/MAX25601DSynchronous Buck LED ControllersGeneral DescriptionBenefits and Features The MAX25601A/B/C/D is a synchronous boost control- ● Integration Minimizes BOM for High-Brightness LED ler followed by a synchronous buck LED controller. The Driver, Saving Space and Cost 4.5V to 40V input voltage range of the boost controller is • Wide Input-Voltage Range from 4.5V to 40V ideal for automotive applications, and acts as a pre-boost • Wide Boost-Output Range up to 65V power supply for the second-stage buck LED controller. • Programmable Switching Frequency Optimizes The synchronous boost is a current-mode controller Component Size that can be be paralleled with another device to provide • External MOSFETs Can be Sized for Appropriate higher output power. A SYNCOUT pin provides the clock Current to drive the RT/SYNCIN pin of the other device, enabling • Synchronous Rectification Provides High Efficiency two-phase 180-degree out-of-phase operation. The boost and Fast Transient Response converter can be programmed with a switching frequency • Average Current-Mode Control for Buck Eliminates of 200kHz to 2.2MHz. Spread spectrum is included to Compensation Components reduce EMI. An internal digital soft-start feature is pro- ● Wide Dimming Ratio Allows High Contrast Ratio vided to enable a smooth power up of the boost output. • Analog Dimming and PWM Dimming Protection features like hiccup mode, overvoltage protec- • Analog Voltage-Controlled PWM Dimming tion, and thermal shutdown are provided. ● Protection Features and Wide Temperature Range The synchronous buck LED controller uses Maxim's F3 Increase System Reliability Architecture, a proprietary average-current-mode control • Short Circuit, Overvoltage, and Thermal Protection scheme to regulate the inductor current at a constant • -40°C to +125°C Operating Temperature Range switching frequency without any control-loop compensa- tion. Inductor current is sensed in the bottom synchronous Simplified Application Circuit n-channel MOSFET. The device operates over a wide INPUT RIN LBOOST BOOST 4.5V to 65V input range at switching frequencies as high VOUT as 1MHz. Both analog and PWM dimming are included. CIN N1 C LED current can be monitored on the IOUTV pin. BOOST INP INN DH1 INPUT AND BIAS Both controllers have high- and low-side gate drivers LX1 with at least 1A peak source and sink-current capabil- SYNC IN/OUT DL1 N2 ity. Adaptive non-overlap control logic prevents shoot- BOOST through currents during transition. Both the boost and the FLTB, IOUTV VOUT MAX25601 buck faults are monitored on the FLT pin. OUT, FB N3 The MAX25601A/C is available in a 32-pin SWTQFN PWM, ANALOG DH2 BUCK L DIMMING BUCK VOUT package and the MAX25601B/D is available in a 28-pin LX2 TSSOP package. The 32-pin package features an BUCK TON CBUCK SETTING DL2 N4 additional switch control that can be used in high-beam/ COMP CSP BUCK low-beam and heads-up display applications. CCOMP RCS_LED VOUT Applications RCOMP CSN ● Automotive Exterior Lighting: High-Beam/Low-Beam/ SHUNT_DRV* Signal/Position Lights, Daytime Running Lights PWM_HUD SHUNT_CTRL* (DRLs), Matrix Light, Pixel Light, and Other Adaptive N5 Front-Light Assemblies * MAX25601A/C ONLY ● Commercial, Industrial, and Architectural Lighting Ordering Information appears at end of data sheet. 19-100564; Rev 3; 1/20
