Datasheet

LT3782A
3
3782afb
The l denotes the specifi cations which apply over the full operating junction
temperature range, otherwise specifi cations are at T
J
= 25°C. V
CC
= 13V, R
SET
= 80k, no load on any outputs, unless otherwise noted.
PARAMETER CONDITIONS MIN TYP MAX UNITS
Overall
Supply Voltage (V
CC
)
l
640V
Supply Current (I
VCC
)V
C
≤ 0.5V (Switching Off), V
CC
≤ 40V 11 16 mA
Shutdown
RUN Threshold
l
2.3 2.45 2.6 V
RUN Threshold Hysteresis 80 mV
Supply Current in Shutdown 1V ≤ RUN ≤ V
REF
, V
CC
≤ 30V
RUN ≤ 0.3V, V
CC
≤ 30V
0.4
40
0.65
90
mA
µA
RUN Pin Input Current V
RUN
= 2.3V
l
–0.5 –2 µA
Voltage Amplifi er g
m
Reference Voltage (V
REF
)
l
2.42
2.4
2.44 2.464
2.488
V
V
Transconductance V
VC
= 1V, ∆I
VC
= ±2µA
l
200 260 370 µmho
Input Current I
FB
V
FB
= V
REF
l
0.2 0.6 µA
V
C
High I
VC
= 0 1.5 V
V
C
Low I
VC
= 0 0.35 0.4 V
Source Current I
VC
V
VC
= 0.7V – 1V, V
FB
= V
REF
– 100mV 8 11 14 µA
Sink Current I
VC
V
VC
= 0.7V – 1V, V
FB
= V
REF
+ 100mV 13 20 28 µA
V
C
Threshold for Switching Off (BGATE1, BGATE2 Low)
l
0.3 V
Soft-Start Current I
SS
V
SS
= 0.1V – 2.8V 6 10 15 µA
Current Amplifi er CA1, CA2
Voltage Gain ∆V
C
/∆V
SENSE
4
Current Limit (V
SENSE1
+
– V
SENSE1
–
) (V
SENSE2
+
– V
SENSE2
–
)V
FB
= 2.3V 55 63 70 mV
Current Limit Mismatch (∆V
SENSE1
– ∆V
SENSE2
), V
FB
= 2.3V –10 10 mV
Input Current (I
SENSE1
+
, I
SENSE1
–
, I
SENSE2
+
, I
SENSE2
–
)∆V
SENSE
= 0V 60 µA
Oscillator
Switching Frequency R
SET
= 130k
R
SET
= 80k
R
SET
= 40k
l
l
l
130
212
386
154
250
465
177
288
533
kHz
kHz
kHz
Synchronization Pulse Threshold on SYNC Pin Rising Edge V
SYNC
0.8 1.2 2 V
Synchronization Frequency Range
(Note: Operation Switching Frequency Equals
Half of the Synchronization Frequency)
R
SET
= 130k
R
SET
= 80k
R
SET
= 40k
180
290
550
240
392
715
kHz
kHz
kHz
V
RSET
R
SET
= 80k 2.3 V
Maximum Duty Cycle V
FB
= V
REF
– 25mV, R
SET
> 80k
R
SET
= 40k
l
l
90
83
94
90
%
%
Duty Cycle Limit R
SET
= 80k, V
DCL
≤ 0.3V
V
DCL
= 1.2V
V
DCL
= V
RSET
50
75
Max Duty Cycle
%
%
DCL Pin Input Current V
DCL
≤ 0.3V
l
–0.1 –0.3 µA
ELECTRICAL CHARACTERISTICS