LT1082_1 Datasheet, PDF (3/12 Pages) Linear Integrated Systems – 1A High Voltage, Efficiency Switching Voltage Regulator

LT1082
ELECTRICAL CHARACTERISTICS The q denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T_A = 25°C. V_IN = 15V, V_C = 0.5V, V_FB = V_REF, output pin open, unless otherwise
specified.
SYMBOL PARAMETER
CONDITIONS
MIN TYP MAX UNITS
I_Q
f
BV
V_FB
V_SAT
I_LIM
∆I_IN
∆I_SW
DC_MAX
Supply Current
Control Pin Threshold
Normal/Flyback Threshold
on Feedback Pin
Switching Frequency
Output Switch Breakdown Voltage
Control Voltage to Switch
Current Transconductance
Flyback Reference Voltage
Change in Flyback Reference Voltage
Flyback Reference Voltage Line Regulation
Flyback Amplifier Transconductance (g_m)
Flyback Amplifier Source
and Sink Current
Output Switch “On” Resistance (Note 2)
Switch Current Limit
(LT1082C)
Switch Current Limit
(LT1082I)
Switch Current Limit
(LT1082M)
Supply Current Increase
During Switch-On Time
Maximum Switch Duty Cycle
Flyback Sense Delay Time
Shutdown Mode Supply Current
Shutdown Mode
Threshold Voltage
3V ≤ V_IN ≤ V_MAX, V_C = 0.6V
Duty Cycle = 0
q
q
800µA ≥ I_FB ≥ 450µA
3V ≤ V_IN ≤ V_MAX, I_SW = 1.5mA
q
I_FB = 60µA
q
60µA ≤ I_FB ≤ 200µA
I_FB = 60µA, 3V ≤ V_IN ≤ V_MAX
∆I_C = ±10µA
V_C = 0.6V Source
q
I_FB = 60µA Sink
q
I_SW = 0.7A (LT1082C), I_SW = 0.5A (LT1082M) q
Duty Cycle = 20%
q
Duty Cycle ≤ 50%
q
Duty Cycle = 80% (Note 3)
q
Duty Cycle = 20%
q
Duty Cycle ≤ 50%
q
Duty Cycle = 80% (Note 3)
q
Duty Cycle = 20%
q
Duty Cycle ≤ 50%
q
Duty Cycle = 80% (Note 3)
q
3V ≤ V_IN ≤ V_MAX, V_C = 0.05V
3V ≤ V_IN ≤ V_MAX
q
4.5 7.0
0.7 0.9 1.1
0.5
1.25
0.58 0.67 0.8
50 60 70
45
75
12
100 115
1.5
17 18.6 20.5
16
21.5
3.5 4.6 6.5
0.01 0.03
150 300 500
15 32
70
30 50
90
0.8 1.2
1.07
2.6
1.0
2.6
0.8
2.4
0.85
2.8
0.8
2.8
0.65
2.6
0.75
3.0
0.7
3.0
0.6
2.8
35
45
85 92
97
1.5
120 350
70 150 250
50
300
mA
V
V
V
kHz
kHz
kHz
V
A/V
V
V
V
%/ V
µmho
µA
µA
Ω
A
A
A
A
A
A
A
A
A
mA /A
%
µs
µA
mV
mV
Note 1: Absolute Maximum Ratings are those values beyond which the
life of a device may be impaired.
Note 2: Measured with V_C in hi clamp, V_FB = 0.8V.
Note 3: For duty cycles (DC) between 50% and 80%, minimum
guaranteed switch current decreases linearly.
sn1082 1082fas
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