MAX25600 Synchronous High-Voltage Four-Switch Buck- Boost LED Controller Electrical Characteristics (continued) (VIN = 12V, VUVEN = 12V, 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.) PARAMETERSYMBOLCONDITIONSMINTYPMAX UNITSPWM DIMMING Internal Ramp Frequency fRAMP 180 200 220 Hz External Sync Frequency Range 30 2000 Hz External Sync Low Level Voltage VLTH 0.4 V External Sync High Level Voltage VHTH 2.0 V DIM Comparator Offset Voltage 170 200 230 mV V Internal PWM Duty Cycle V PWM = 1.0V 28.6 PWM % VPWM = 1.7V 53.6 DIM Voltage for 100% Duty Cycle 3.2 V DIMMING MOSFET GATE DRIVER Peak Pullup Current IDIMOUTPU PWM = 0V, (VISP - VDIMOUT) = 5V 30 50 85 mA Peak Pulldown Current IDIMOUTPD (VISP - VDIMOUT) = 0V 10 25 45 mA DIMOUT Low Voltage with -4.6 -5.0 -5.4 V Respect to ISP DIM Turn-On Comparator ISP rising 5.7 V DIM Turn-Off Comparator ISP falling 5.3 V FAULT Minimum On Time (Buck) tON_MIN 150 240 ns FB Overvoltage Threshold VTH_OVP FB rising 1.22 1.24 1.28 V FB Overvoltage Hysteresis 0.1 V Short Fault Threshold FB falling 150 mV Soft-Start Pullup Current 15 µA FLT Output Voltage ISINK is 1mA after fault 0.05 0.3 V FLT Leakage Current VFLT = 5.5V 1 µA Hiccup Activation Threshold 400 mV OFF TIME CONTROL Linear Range of Pulse Doubler 5 µs THERMAL SHUTDOWN Thermal Shutdown Threshold TSHUTDOWN Temperature Rising 165 °C Thermal Shutdown Hysteresis THYS 15 °C Note 1: The MAX25600 is guaranteed to meet performance specifications over the -40°C to +125°C operating junction-temperature range. High junction temperatures degrade operating lifetimes. Operating lifetime is derated for junction temperatures greater than +125°C. Note 2: The MAX25600 includes overtemperature protection that is intended to protect the device during momentary overload conditions. Junction temperature will exceed the maximum operating junction temperature when overtemperature protection is active. Continuous operation above the specified absolute maximum operating junction temperature may impair device reliability. www.maximintegrated.com Maxim Integrated │ 5