MAX25610A/MAX25610B Synchronous Buck and Buck-Boost LED Driver/DC-DC Converter Electrical Characteristics (continued) (INP = 12V, INN = AGND = PGND, PWMDIM = INN, Limits are 100% tested at TA = 25°C and TA = 125°C. Limits over the operating temperature range and relevant supply voltage range are guaranteed by design and characterization from TA = -40°C to TA = 125°C.) PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITSINTERNAL OSCILLATOR MAX25610A 370 400 430 kHz Switching Frequency fSW Dithering off MAX25610B 2 2.18 2.36 MHz MAX25610A only 100 Minimum On-Time tON_MIN ns MAX25610B only 56 85 Maximum Duty Cycle DMAX MAX25610A only 89 91 94 % Frequency Dither +6 % OVERVOLTAGE Overvoltage Threshold Rising INPSTOP Buck-boost mode INP rising 33 34.5 36 V Overvoltage Threshold Falling INPSTART Buck-boost mode INP falling 32 33.3 34.5 V PWM DIMMING (PWMDIM) Set with external RC on PWMFRQ pin, Ramp Frequency − 3.33 × 3 = 10 f 200 1000 Hz DIM R × PWMFRQ CPWMFRQ PWM Frequency Accuracy Ideal external resistor and capacitor -10 +10 % DIM Comparator Offset Voltage VDIMOFS Voltages referred to INN 0.2 V DIM Comparator for 100% Duty Cycle 3.3 V V PWM Duty Cycle Accuracy PWMDIM - VINN = 0.9V 23.5 25 26.5 % VPWMDIM - VINN = 2.3V 72 75 78 PWMDIM Logic-Level Low VPWMDIM_H 0.4 V PWMDIM Logic-Level High VPWMDIM_L 2.0 V ANALOG DIMMING (REFI)/INTERNAL SENSE Buck mode 8.5V < V RREFI = 4.59kΩ INP - VPGND < 33V (Note 3) (Note 4) 2.75 2.85 2.95 RREFI = 8.76kΩ Buck mode 8.5V (Note 3) 1.4325 1.5 1.5675 Current Regulation < VINP - VPGND < R A REFI = 21.8kΩ, 33V TJ = 0°C to +125°C 0.564 0.6 0.636 (Note 3) Buck mode 8.5V RREFI = 21.8kΩ, < VINP - VPGND TJ = -40°C to +125°C 0.550 0.6 0.650 < 33V (Note 3) www.maximintegrated.com Maxim Integrated │ 4