Datasheet

LT1176/LT1176-5
3
11765fb
ELECTRICAL CHARACTERISTICS
PARAMETER CONDITIONS MIN TYP MAX UNITS
Switch ON Voltage (Note 2) I
SW
= 0.2A
I
SW
= 1A
l
l
1.1
1.4
V
V
Switch OFF Leakage V
IN
= 25V, V
SW
= 0
V
IN
= V
MAX
, V
SW
= 0 (Note 8)
150
250
µA
µA
Supply Current (Note 3) V
FB
= 2.5V, V
IN
≤ 35V
V
SHDN
= 0.1V (Device Shutdown) (Note 9)
l
l
7.5
140.0
10
300
mA
µA
Minimum Supply Voltage Normal Mode
Startup Mode (Note 4)
l
l
7.3
3.5
8.0
4.8
V
V
Switch Current Limit (Note 5) I
LIM
Open
R
LIM
= 10k (Note 6)
R
LIM
= 7k (Note 6)
l
1.2 1.7
1.2
0.8
2.2 A
A
A
Maximum Duty Cycle
l
85 90 %
Switching Frequency
V
FB
= 0V Through 2k (Note 5) (LT1176)
V
SENSE
= 0V (Note 5) (LT1176-5)
l
90
85
100
20
20
110
120
kHz
kHz
kHz
kHz
Switching Frequency Line Regulation 8V ≤ V
IN
≤ V
MAX
(Note 8)
l
0.03 0.1 %/V
Error Amplifier Voltage Gain (Note 10) 1V ≤ V
C
≤ 4V 2000 V/V
Error Amplifier Transconductance (Note 10) 3700 5000 8000 µmho
Error Amplifier Source and Sink Current Source (V
FB
= 2V or V
SENSE
= 4V)
Sink (V
FB
= 2.5V or V
SENSE
= 5.5V)
100.0
0.7
140
1.0
225.0
1.6
µA
mA
Feedback Pin Bias Current (LT1176) V
FB
= V
REF
l
0.5 2 µA
Reference Voltage (LT1176) V
C
= 2V
l
2.155 2.21 2.265 V
Reference Voltage Tolerance (LT1176) V
REF
(Nominal) = 2.21V
All Conditions of Input Voltage, Output Voltage,
Temperature and Load Current
l
±0.5
±1.0
±2
±3
%
%
Sense Voltage (LT1176-5) V
C
= 2V
l
4.85 5 5.15 V
Sense Voltage Tolerance (LT1176-5) V
OUT
(Nominal) = 5V
All Conditions of Input Voltage,
Temperature and Load Current
l
±0.5
±0.1
±2
±3
%
%
Sense Pin Divider Resistance (LT1176-5) 3 5 8 kΩ
Output Voltage Line Regulation 8V ≤ V
IN
≤ V
MAX
(Note 8)
l
0.005 0.02 %/V
V
C
Voltage at 0% Duty Cycle
Overtemperature
l
1.5
–4.0
V
mV/°C
Multiplier Reference Voltage 24 V
Shutdown Pin Current V
SHDN
= 5V
V
SHDN
≤ V
THRESHOLD
(@ 2.5V)
l
l
5 10 20
50
µA
µA
Shutdown Thresholds Switch Duty Cycle = 0
Fully Shutdown
l
l
2.2
0.1
2.45
0.30
2.7
0.5
V
V
Status Window As a Percent of Output Voltage ±4 ±5 ±6 %
Status High Level I
STATUS
= 10µA Sourcing
l
3.5 4.5 5.0 V
The l 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.