Linear Technology Analog Devices LT8708, Datasheet

Page: 5 / 64

LT8708
5
Rev 0
For more information www.analog.com
PARAMETER CONDITIONS MIN TYP MAX UNITS
SWEN Internal Pull-Down Release Voltage SHDN = 3V
l
0.75 0.8 V
MODE Pin Continuous Conduction Mode (CCM)
Threshold
l
0.4 V
MODE Pin Hybrid DCM/CCM Mode (HCM) Range
l
0.8 1.2 V
MODE Pin Discontinuous Conduction Mode (DCM)
Range
l
1.6 2.0 V
MODE Pin Burst Mode Operation Threshold
l
2.4 V
DIR Pin Forward Operation Threshold
l
1.6 V
DIR Pin Reverse Operation Threshold
l
1.2 V
RVSOFF Output Voltage Low I
RVSOFF
= 200μA
l
0.08 0.5 V
RVSOFF Falling Threshold Voltage
l
1.155 1.209 1.275 V
RVSOFF Threshold Voltage Hysteresis 165 mV
Soft-Start Charging Current V
SS
= 0V 13 19 25 μA
ICN Rising Threshold for FDCM Operation MODE = 1V (HCM), DIR = 3.3V
l
235 255 280 mV
ICN Falling Threshold for CCM Operation MODE = 1V (HCM), DIR = 3.3V
l
185 205 235 mV
IMON_INP Rising Threshold for RDCM Operation MODE = 1V (HCM), DIR = 0V
l
235 255 280 mV
IMON_INP Falling Threshold for CCM Operation MODE = 1V (HCM), DIR = 0V
l
185 205 235 mV
Voltage Regulation Loops (Refer to Block Diagram to Locate Amplifiers)
Regulation Voltage for FBOUT
Regulate V
C
to 1.2V
l
1.193 1.207 1.222 V
Regulation Voltage for FBIN Regulate V
C
to 1.2V
l
1.184 1.205 1.226 V
Line Regulation for FBOUT and FBIN Error Amp
Reference Voltage
V
INCHIP
= 12V to 80V. Not Switching 0.002 0.005 %/V
FBOUT Pin Bias Current Current Out of Pin 15 nA
FBOUT Error Amp EA4 g
m
345 μmho
FBOUT Error Amp EA4 Voltage Gain 245 V/V
VOUTLOMON Voltage Activation Threshold Falling
l
1.185 1.207 1.225 V
VOUTLOMON Threshold Voltage Hysteresis 24 mV
VOUTLOMON Pin Bias Current V
VOUTLOMON
=1.24V, Current Into Pin
V
VOUTLOMON
=1.17V, Current Into Pin
l
0.8
0.01
1 1.2
μA
μA
FBIN Pin Bias Current Current Out of Pin 10 nA
FBIN Error Amp EA3 g
m
235 μmho
FBIN Error Amp EA3 Voltage Gain 150 V/V
VINHIMON Voltage Activation Threshold Rising
l
1.185 1.207 1.23 V
VINHIMON Threshold Voltage Hysteresis 24 mV
VINHIMON Pin Bias Current V
VINHIMON
= 1.17V, Current Out of Pin
V
VINHIMON
= 1.24V, Current Out of Pin
l
0.8
0.03
1 1.2
μA
μA
Current Regulation Loops (Refer to Block Diagram to Locate Amplifiers)
Regulation Voltages for IMON_INP and IMON_OP
V
C
= 1.2V
l
1.185 1.209 1.231 V
Regulation Voltages for IMON_INN and IMON_ON V
C
=1.2V
l
1.185 1.21 1.24 V
ELECTRICAL CHARACTERISTICS
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
INCHIP
= 12V, SHDN = 3V, DIR = 3.3V unless otherwise noted (Note 3).