LT1074_15 Datasheet, PDF (3/16 Pages) Linear Technology – Step-Down Switching Regulator

LT1074/LT1076
ELECTRICAL CHARACTERISTICS The ● denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T_A = 25°C. T_j = 25°C, V_IN = 25V, unless otherwise noted.
PARAMETER
Switch “On” Voltage (Note 2)
Switch “Off” Leakage
Supply Current (Note 3)
Minimum Supply Voltage
Switch Current Limit (Note 5)
Maximum Duty Cycle
Switching Frequency
Switching Frequency Line Regulation
Error Amplifier Voltage Gain (Note 7)
Error Amplifier Transconductance
Error Amplifier Source and Sink Current
Feedback Pin Bias Current
Reference Voltage
Reference Voltage Tolerance
Reference Voltage Line Regulation
V_C Voltage at 0% Duty Cycle
Multiplier Reference Voltage
Shutdown Pin Current
Shutdown Thresholds
Thermal Resistance Junction to Case
CONDITIONS
LT1074
LT1076
LT1074
LT1076
I_SW = 1A, T_j ≥ 0°C
I_SW = 1A, T_j < 0°C
I_SW = 5A, T_j ≥ 0°C
I_SW = 5A, T_j < 0°C
I_SW = 0.5A
I_SW = 2A
V_IN ≤ 25V, V_SW = 0
V_IN = V_MAX, V_SW = 0 (Note 8)
V_IN = 25V, V_SW = 0
V_IN = V_MAX, V_SW = 0 (Note 8)
V_FB = 2.5V, V_IN ≤ 40V
40V < V_IN < 60V
V_SHUT = 0.1V (Device Shutdown) (Note 9)
Normal Mode
Startup Mode (Note 4)
LT1074
LT1076
I_LIM Open
R_LIM = 10k (Note 6)
R_LIM = 7k (Note 6)
I_LIM Open
R_LIM = 10k (Note 6)
R_LIM = 7k (Note 6)
T_j ≤ 125°C
T_j > 125°C
V_FB = 0V through 2kΩ (Note 5)
8V ≤ V_IN ≤ V_MAX (Note 8)
1V ≤ V_C ≤ 4V
Source (V_FB = 2V)
Sink (V_FB = 2.5V)
V_FB = V_REF
V_C = 2V
V_REF (Nominal) = 2.21V
All Conditions of Input Voltage, Output
Voltage, Temperature and Load Current
8V ≤ V_IN ≤ V_MAX (Note 8)
Over Temperature
V_SH = 5V
V_SH ≤ V_THRESHOLD (≅2.5V)
Switch Duty Cycle = 0
Fully Shut Down
LT1074
LT1076
MIN TYP MAX UNITS
1.85
V
2.1
V
2.3
V
2.5
V
●
1.2
V
●
1.7
V
5
300
µA
10
500
µA
150
µA
250
µA
●
8.5
11
mA
●
9
12
mA
●
140 300
µA
●
7.3
8
V
●
3.5
4.8
V
● 5.5
6.5
8.5
A
4.5
A
3
A
●2
2.6
3.2
A
1.8
A
1.2
A
● 85
90
%
90
100 110
kHz
● 85
120
kHz
● 85
125
kHz
20
kHz
●
0.03
0.1
%/V
2000
V/V
3700 5000 8000 µmho
100 140 225
µA
0.7
1
1.6
mA
●
0.5
2
µA
● 2.155 2.21 2.265
V
±0.5 ±1.5
%
●
±1
±2.5
%
●
●
●5
●
● 2.2
● 0.1
0.005 0.02
%/V
1.5
V
–4
mV/°C
24
V
10
20
µA
50
µA
2.45
2.7
V
0.3
0.6
V
2.5
°C/W
4.0
°C/W
sn1074 1074fds
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