Datasheet

LT3742
3
3742fa
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
elecTrical characTerisTics
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
IN
= 5V unless otherwise specified.
PARAMETER CONDITIONS MIN TYP MAX UNITS
FB Pin Bias Current V
FB
= 0.8V, V
C
= 0.4V 50 200 nA
FB Pin Voltage Matching –4 0 4 mV
Error Amplifier Transconductance 250 µmho
Error Amplifier Voltage Gain 500 V/V
V
C
Pin Source Current V
FB
= 0.6V 15 µA
V
C
Pin Sink Current V
FB
= 1V 15 µA
Controller Switching Frequency 440 500 560 kHz
Switching Phase 180 Deg
Maximum Current Sense Voltage V
SENSE
–
= 3.3V
l
50 60 70 mV
Current Sense Matching Between Controllers ±5 %
Current SENSE Pins Total Current SENSE
–
, SENSE
+
= 0V
SENSE
–
, SENSE
+
= 3.3V
–1.0
40
mA
µA
Gate Rise Time C
LOAD
= 3300pF 40 ns
Gate Fall Time C
LOAD
= 3300pF 60 ns
Gate On Voltage (V
G
– V
SW
) V
BIAS
= 12V 6.0 6.7 7.0 V
Gate Off Voltage (V
G
– V
SW
) V
BIAS
= 12V 0.4 0.75 V
PG Pin Voltage Low I
PG
= 100µA 0.20 0.5 V
Lower PG Trip Level (Relative to V
FB
) V
FB
Increasing –7 –10 –13 %
Lower PG Trip Level (Relative to V
FB
) V
FB
Decreasing –10 –13 –16 %
Upper PG Trip Level (Relative to V
FB
) V
FB
Increasing 7 10 13 %
Upper PG Trip Level (Relative to V
FB
) V
FB
Decreasing 4 7 10 %
PG Pin Leakage Current V
PG
= 2V 0.1 µA
PG Pin Sink Current V
PG
= 0.5V 200 500 µA
Bias Pin Voltage V
IN
+ 6.6 V
IN
+ 7 V
IN
+ 7.7 V
SWB Pin Current Limit 250 340 500 mA
SWB Pin Leakage Current V
SWB
= 12V 0.01 1 µA
Bias Supply Switching Frequency 0.88 1.0 1.12 MHz
Note 2: The LT3742E is guaranteed to meet performance specifications
from 0°C to 125°C operating junction temperature range. Specifications
over the –40°C to 125°C operating junction temperature range are
assured by design, characterization and correlation with statistical process
controls.