link to page 32 link to page 30 link to page 32 link to page 30 LTC3894 ELECTRICAL CHARACTERISTICSThe l denotes the specifications which apply over the specified operatingjunction temperature range, otherwise specifications are at TA = 25°C. VIN = 12V, unless otherwise noted. (Note 2)SYMBOLPARAMETERCONDITIONSMINTYPMAXUNITS IQ(VINR) Total Input Supply Current in Regulation at VIN = 12V No Load in Burst Mode (Note 7) Figure 14 Circuit, VOUT = 3.3V 16 µA Figure 12 Circuit, VOUT = 5V 22 µA VIN = 48V Figure 14 Circuit, VOUT = 3.3V 9 µA Figure 12 Circuit, VOUT = 5V 11 µA Output Sensing VFB Regulated Feedback Voltage VITH = 1.2V (Note 8) l 0.788 0.800 0.812 V Feedback Voltage Line Regulation VIN = 4.5V to 150V (Note 8) ±0.002 0.015 %/V Feedback Voltage Load Regulation VITH = 0.6V to 1.8V (Note 8) 0.03 0.15 % gm(EA) Error Amplifier Transconductance VITH = 1.2V, ∆IITH = ±5µA (Note 8) 2 mS IFB Feedback Input Bias Current –10 ±50 nA Current Sensing V – SENSE(MAX) Maximum Current Sense Threshold VFB = 0.7V, VSENSE = 3.3V l 88 100 112 mV (V + – SENSE – VSENSE ) I + + SENSE SENSE+ Pin Input Current VSENSE = 3.3V 0.1 1 µA I – – SENSE SENSE– Pin Input Current in Non-Sleep VSENSE = 3.3V 200 300 µA Mode (Note 6) V – SENSE = 5V 880 1260 µA Start-Up and Shutdown VRUN RUN Pin Enable Threshold VRUN Rising l 1.14 1.24 1.34 V VRUNHYS RUN Pin Hysteresis 125 mV ISS Soft-Start Pin Charging Current VSS = 0V or 0V to 0.8V 8 11 14 µA VOVLO Overvoltage Lockout Threshold VOVLO Rising Up l 0.77 0.8 0.82 V Hysteresis 30 mV Gate Driver and VIN-Cap LDO VUVLO Undervoltage Lockout DRVUV = 0 (VIN-VCAP) Ramping Up Threshold l 3.4 3.75 4.3 V (VIN-VCAP) Ramping Down Threshold l 3.25 3.50 3.75 V Hysteresis 0.25 V DRVUV = Floating (VIN-VCAP) Ramping Up Threshold l 5.5 6.0 6.55 V (VIN-VCAP) Ramping Down Threshold l 5.2 5.55 5.85 V Hysteresis 0.45 V VCAP Gate Bias LDO Output Voltage (VIN-VCAP) ICAP = 0mA, 9V ≤ VIN ≤ 150V (Note 9) l 7.5 8.0 8.5 V VCAPDROP Gate Bias LDO Dropout Voltage (VIN-VCAP) VIN = 5V, ICAP = 15mA (Note 9) 4.1 4.4 V ∆VCAP(LOAD) Gate Bias LDO Load Regulation ICAP = 0mA to 20mA –2.8 –1.3 % RUP Gate Pull-Up Resistance Gate High 2 Ω RDN Gate Pull-Down Resistance Gate Low 0.9 Ω tON(MIN) Gate Minimum On-Time (Note 10) 125 ns Switching Frequency and Clock Synchronization f Programmable Switching Frequency RFREQ = 25kΩ 100 kHz RFREQ = 64.9kΩ 375 440 505 kHz RFREQ = 105kΩ 810 kHz Rev. A For more information www.analog.com 3 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Order Information Electrical Characteristics Pin Configuration Electrical Characteristics Typical Performance Characteristics Pin Functions Functional Diagram Operation Applications Information Typical Applications Package Description Revision History Typical Application Related Parts