Datasheet LT8710 (Analog Devices) - 4
| Manufacturer | Analog Devices |
| Description | Synchronous SEPIC/Inverting/Boost Controller with Output Current Control |
| Pages / Page | 44 / 4 — e lecTrical characTerisTics The. denotes the specifications which apply … |
| File Format / Size | PDF / 657 Kb |
| Document Language | English |
e lecTrical characTerisTics The. denotes the specifications which apply over the full operating
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LT8710
e lecTrical characTerisTics The
l
denotes the specifications which apply over the full operating temperature range, otherwise specifications for each channel are at TA = 25°C. VIN = 12V, VEN/FBIN = 12V, VBIAS = 12V, unless otherwise noted (Note 2). PARAMETER CONDITIONS MIN TYP MAX UNITS
Positive FBX Pin Bias Current VFBX = Positive FBX Reg Voltage, Current into Pin l 81.9 83.7 85.6 µA Negative FBX Pin Bias Current VFBX = Negative FBX Reg Voltage, Current Out of Pin l 81.1 83.1 85.2 µA FBX Amp Transconductance, ΔI = 2μA 200 µmhos EA1 or EA2 FBX Amp Voltage Gain, EA1 or EA2 70 V/V FBX Line Regulation 4.5V ≤ VIN ≤ 80V, VBIAS = 0V –0.02 –0.001 0.02 %/V Output Current Sense Regulation VISN = 80V, VFBX = 1V l 43 50 57 mV Voltage, VISP – VISN VISN = 12V, VFBX = 1V l 43 50 57 mV VISN = 0V, VFBX = 1V l 40 50 60 mV VISN = 12V, VFBX = 1V, INTVEE in UVLO and VSS > 1.8V l 17 25 34 mV IMON Regulation Voltage, EA3 VFBX = 1V l 1.184 1.213 1.24 V VFBX = 1V, INTVEE in UVLO and VSS > 1.8V l 0.885 0.916 0.947 V Output Current Sense Amp ΔI = 10μA 1000 µmhos Transconductance, A6 Output Current Sense Amp Voltage 11.9 V/V Gain, A6 Output Current Sense Amp Input Negative Input Range, VISP – VISN –51.8 mV Dynamic Range, A6 Positive Input Range, VISP – VISN 500 mV IMON Amp Transconductance, EA3 ΔI = 2μA, VFBX = 1V 165 µmhos IMON Amp Voltage Gain, EA3 VFBX = 1V 65 V/V EN/FBIN Input Regulation Voltage, EA4 VFBX = 1V l 1.55 1.607 1.662 V EN/FBIN Amp Transconductance, EA4 ΔI = 2µA, VFBX = 1V 140 µmhos EN/FBIN Amp Voltage Gain, EA4 VFBX = 1V 55 V/V MODE Forced CCM Threshold To Exit Forced CCM Mode, MODE Rising l 1.19 1.224 1.258 V To Enter Forced CCM Mode, MODE Falling l 1.125 1.175 1.23 V MODE Forced CCM Threshold 49 mV Hysteresis DCM Comparator Threshold in VISN = 80V, To Enter DCM Mode, VISP – VISN Falling l –4.5 2.8 10 mV Pulse-Skipping Mode, MODE = 2V VISN = 12V, To Enter DCM Mode, VISP – VISN Falling l –4.5 2.8 10 mV VISN = 0V, To Enter DCM Mode, VISP – VISN Falling l –7.5 2.8 13 mV DCM Comparator Threshold in VISN = 80V, To Enter DCM Mode, VISP – VISN Falling l –220 –300 –380 mV Forced CCM, MODE =0V VISN = 12V, To Enter DCM Mode, VISP – VISN Falling l –220 –300 –380 mV VISN = 0V, To Enter DCM Mode, VISP – VISN Falling l –220 –300 –380 mV
Oscillator
Switching Frequency, fOSC RT = 46.4k l 640 750 860 kHz RT = 357k l 85 100 115 kHz Switching Frequency in Foldback Compared to Normal fOSC 1/5 ratio Switching Frequency Range Free-Running or Synchronizing l 100 750 kHz SYNC High Level for Sync l 1.5 V SYNC Low Level for Sync l 0.4 V SYNC Clock Pulse Duty Cycle VSYNC = 0V to 3V 20 80 % Recommended Min SYNC Ratio 3/4 fSYNC/fOSC 8710f 4 For more information www.linear.com/LT8710
e lecTrical characTerisTics The
l
denotes the specifications which apply over the full operating temperature range, otherwise specifications for each channel are at TA = 25°C. VIN = 12V, VEN/FBIN = 12V, VBIAS = 12V, unless otherwise noted (Note 2). PARAMETER CONDITIONS MIN TYP MAX UNITS
Positive FBX Pin Bias Current VFBX = Positive FBX Reg Voltage, Current into Pin l 81.9 83.7 85.6 µA Negative FBX Pin Bias Current VFBX = Negative FBX Reg Voltage, Current Out of Pin l 81.1 83.1 85.2 µA FBX Amp Transconductance, ΔI = 2μA 200 µmhos EA1 or EA2 FBX Amp Voltage Gain, EA1 or EA2 70 V/V FBX Line Regulation 4.5V ≤ VIN ≤ 80V, VBIAS = 0V –0.02 –0.001 0.02 %/V Output Current Sense Regulation VISN = 80V, VFBX = 1V l 43 50 57 mV Voltage, VISP – VISN VISN = 12V, VFBX = 1V l 43 50 57 mV VISN = 0V, VFBX = 1V l 40 50 60 mV VISN = 12V, VFBX = 1V, INTVEE in UVLO and VSS > 1.8V l 17 25 34 mV IMON Regulation Voltage, EA3 VFBX = 1V l 1.184 1.213 1.24 V VFBX = 1V, INTVEE in UVLO and VSS > 1.8V l 0.885 0.916 0.947 V Output Current Sense Amp ΔI = 10μA 1000 µmhos Transconductance, A6 Output Current Sense Amp Voltage 11.9 V/V Gain, A6 Output Current Sense Amp Input Negative Input Range, VISP – VISN –51.8 mV Dynamic Range, A6 Positive Input Range, VISP – VISN 500 mV IMON Amp Transconductance, EA3 ΔI = 2μA, VFBX = 1V 165 µmhos IMON Amp Voltage Gain, EA3 VFBX = 1V 65 V/V EN/FBIN Input Regulation Voltage, EA4 VFBX = 1V l 1.55 1.607 1.662 V EN/FBIN Amp Transconductance, EA4 ΔI = 2µA, VFBX = 1V 140 µmhos EN/FBIN Amp Voltage Gain, EA4 VFBX = 1V 55 V/V MODE Forced CCM Threshold To Exit Forced CCM Mode, MODE Rising l 1.19 1.224 1.258 V To Enter Forced CCM Mode, MODE Falling l 1.125 1.175 1.23 V MODE Forced CCM Threshold 49 mV Hysteresis DCM Comparator Threshold in VISN = 80V, To Enter DCM Mode, VISP – VISN Falling l –4.5 2.8 10 mV Pulse-Skipping Mode, MODE = 2V VISN = 12V, To Enter DCM Mode, VISP – VISN Falling l –4.5 2.8 10 mV VISN = 0V, To Enter DCM Mode, VISP – VISN Falling l –7.5 2.8 13 mV DCM Comparator Threshold in VISN = 80V, To Enter DCM Mode, VISP – VISN Falling l –220 –300 –380 mV Forced CCM, MODE =0V VISN = 12V, To Enter DCM Mode, VISP – VISN Falling l –220 –300 –380 mV VISN = 0V, To Enter DCM Mode, VISP – VISN Falling l –220 –300 –380 mV
Oscillator
Switching Frequency, fOSC RT = 46.4k l 640 750 860 kHz RT = 357k l 85 100 115 kHz Switching Frequency in Foldback Compared to Normal fOSC 1/5 ratio Switching Frequency Range Free-Running or Synchronizing l 100 750 kHz SYNC High Level for Sync l 1.5 V SYNC Low Level for Sync l 0.4 V SYNC Clock Pulse Duty Cycle VSYNC = 0V to 3V 20 80 % Recommended Min SYNC Ratio 3/4 fSYNC/fOSC 8710f 4 For more information www.linear.com/LT8710
