LTC7871 ELECTRICAL CHARACTERISTICSThe l denotes the specifications which apply over the full operatingtemperature range, otherwise specifications are at TA = 25°C, VHIGH = 48V, VRUN = 5V unless otherwise noted. (Note 2) SYMBOLPARAMETERCONDITIONSMINTYPMAXUNITS Synchronizable Frequency SYNC = External Clock l 60 750 kHz Spread Spectrum Frequency VSYNC = 5V, RFREQ = 51.1k, MFR_SSFM = 0x00 –12 12 % Modulation Range θ2 – θ1 Phase 2 Relative to Phase 1 180 Deg θ3 – θ1 Phase 3 Relative to Phase 1 60 Deg θ4 – θ1 Phase 4 Relative to Phase 1 240 Deg θ5 – θ1 Phase 5 Relative to Phase 1 120 Deg θ6 – θ1 Phase 6 Relative to Phase 1 300 Deg θCLKOUT – θ1 CLKOUT Phase to Phase 1 30 Deg Clock Output High Voltage ILOAD = 0.5mA V5 – 0.2 V5 V Clock Output Low Voltage ILOAD = –0.5mA 0.2 V SYNC Pin Input Threshold SYNC Pin Rising 2 V SYNC Pin Falling 1.1 V SYNC Pin Input Resistance 100 kΩ Power Good and FAULT PGOOD Voltage Low IPGOOD = 2mA 0.1 0.3 V PGOOD Leakage Current VPGOOD = 5V ±1 µA PGOOD Trip Level, VFBHIGH/VFBLOW VFBHIGH/VFBLOW Ramping Negative –10 % With Respect to the Regulated Voltage VFBHIGH/VFBLOW Ramping Positive 10 % PGOOD Delay PGOOD Pin High to Low 40 µs FAULT Voltage Low IFAULT = 2mA 0.1 0.3 V FAULT Voltage Leakage Current VFAULT = 5V ±1 µA FAULT Delay FAULT Pin High to Low 120 µs VLOW OV Comparator Threshold 1.15 1.2 1.25 V VLOW OV Comparator Hysteresis VOVLOW > 1.2V 5 µA VHIGH OV Comparator Threshold 1.15 1.2 1.25 V VHIGH OV Comparator Hysteresis VOVHIGH > 1.2V 5 µA VHIGH UV Comparator Threshold 1.15 1.2 1.25 V VHIGH UV Comparator Hysteresis VUVHIGH < 1.2V 5 µA PWM Outputs PWM Output High Voltage ILOAD = 0.5mA l V5 – 0.5 V PWM Output Low Voltage ILOAD = –0.5mA l 0.5 V PWM Output Current in Hi-Z State ±5 µA DIGITAL I/O: CSB, SCLK, SDI, SDO VIL Digital Input Low Voltage Pins CSB, SCLK, SDI 0.5 V VIH Digital Input High Voltage Pins CSB, SCLK, SDI 1.8 V VOL Digital Output Voltage Low Pin SDO, Sinking 1mA 0.3 V RCSB CSB Pin Pull-Up Resistor 300 kΩ RSCLK SCLK Pin Pull-Down Resistor 300 kΩ RSDI SDI Pin Pull-Down Resistor 300 kΩ Rev. 0 6 For more information www.analog.com Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Order Information Pin Configuration Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Serial Port Serial Port Register Details Typical Applications Package Description Typical Application Related Parts