Datasheet
4
LT1374
1374fd
Switch Voltage Drop
SWITCH CURRENT (A)
0
SWITCH VOLTAGE (mV)
250
200
400
125°C
25°C
350
300
45
1374 G18
150
100
50
0
1
2
3
500
450
–40°C
Feedback Pin Voltage
TEMPERATURE (°C)
–50
2.430
2.425
2.420
2.415
2.410
100
1374 G03
–25 0 25 50 75 125
FEEDBACK VOLTAGE (V)
Switch Peak Current Limit
DUTY CYCLE (%)
0
SWITCH PEAK CURRENT (A)
6.5
6.0
5.5
5.0
4.5
4.0
3.5
3.0
80
1374 G02
20
40
60
100
TYPICAL
MINIMUM
Shutdown Pin Bias Current
TEMPERATURE (°C)
–50
500
400
300
200
8
4
0
25 75
1374 G04
–25 0
50 100 125
CURRENT (µA)
CURRENT REQUIRED TO FORCE SHUTDOWN
(FLOWS OUT OF PIN). AFTER SHUTDOWN,
CURRENT DROPS TO A FEW µA
AT 2.38V STANDBY THRESHOLD
(CURRENT FLOWS OUT OF PIN)
Standby and Shutdown Thresholds
Shutdown Supply Current
JUNCTION TEMPERATURE (°C)
–50
2.40
2.36
2.32
0.8
0.4
0
25 75
1374 G05
–25 0
50 100 125
SHUTDOWN PIN VOLTAGE (V)
STANDBY
START-UP
SHUTDOWN
INPUT VOLTAGE (V)
0
INPUT SUPPLY CURRENT (µA)
25
20
15
10
5
0
5 101520
1374 G06
25
V
SHDN
= 0V
Note 5: Boost current is the current flowing into the boost pin with the pin
held 5V above input voltage. It flows only during switch on time.
Note 6: V
IN
supply current is the current drawn when the BIAS pin is held
at 5V and switching is disabled. If the BIAS pin is unavailable or open
circuit, the sum of V
IN
and BIAS supply currents will be drawn by the V
IN
pin.
Note 7: Switch on resistance is calculated by dividing V
IN
to V
SW
voltage
by the forced current (4.5A). See Typical Performance Characteristics for
the graph of switch voltage at other currents.
ELECTRICAL CHARACTERISTICS
Note 8: Transconductance and voltage gain refer to the internal amplifier
exclusive of the voltage divider. To calculate gain and transconductance,
refer to the SENSE pin on the fixed voltage parts. Divide values shown by
the ratio V
OUT
/2.42.
Note 9: Slope compensation is the current subtracted from the switch
current limit at 80% duty cycle. See Maximum Output Load Current in the
Applications Information section for further details.
TYPICAL PERFOR A CE CHARACTERISTICS
UW