Datasheet

2
LTC3717
sn3717 3717fs
(Note 1)
Input Supply Voltage (V
CC
, I
ON
) .................36V to –0.3V
Boosted Topside Driver Supply Voltage
(BOOST) ................................................... 42V to –0.3V
SW Voltage .................................................. 36V to –5V
EXTV
CC
, (BOOST – SW), RUN/SS,
PGOOD Voltages....................................... 7V to –0.3V
V
REF
, V
RNG
Voltages ...............(INTV
CC
+ 0.3V) to –0.3V
I
TH
, V
FB
Voltages...................................... 2.7V to –0.3V
TG, BG, INTV
CC
, EXTV
CC
Peak Currents.................... 2A
TG, BG, INTV
CC
, EXTV
CC
RMS Currents .............. 50mA
Operating Ambient Temperature
Range (Note 4) ................................... –40°C to 85°C
Junction Temperature (Note 2)............................ 125°C
Storage Temperature Range ................. –65°C to 150°C
Lead Temperature (Soldering, 10 sec)..................300°C
ORDER PART
NUMBER
LTC3717EGN
Consult LTC Marketing for parts specified with wider operating temperature ranges.
T
JMAX
= 125°C, θ
JA
= 130°C/W
The ● denotes specifications which apply over the full operating
temperature range, otherwise specifications are T
A
= 25°C. V
CC
= 15V unless otherwise noted.
ABSOLUTE AXI U RATI GS
WWWU
PACKAGE/ORDER I FOR ATIO
UU
W
ELECTRICAL CHARACTERISTICS
TOP VIEW
GN PACKAGE
16-LEAD PLASTIC SSOP
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
RUN/SS
PGOOD
V
RNG
I
TH
SGND
I
ON
V
FB
V
REF
BOOST
TG
SW
PGND
BG
INTV
CC
V
CC
EXTV
CC
GN PART
MARKING
3717
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
Main Control Loop
I
Q
Input DC Supply Current
Normal 1000 2000 µA
Shutdown Supply Current V
RUN/SS
= 0V 15 30 µA
V
FB
Feedback Voltage Accuracy I
TH
= 1.2V (Note 3), V
REF
= 2.4V –0.65 0.65 %
∆V
FB(LINEREG)
Feedback Voltage Line Regulation V
CC
= 4V to 36V, I
TH
= 1.2V (Note 3) 0.002 %/V
∆V
FB(LOADREG)
Feedback Voltage Load Regulation I
TH
= 0.5V to 1.9V (Note 3) ● –0.05 –0.3 %
g
m(EA)
Error Amplifier Transconductance I
TH
= 1.2V (Note 3) 0.93 1.13 1.33 mS
t
ON
On-Time I
ON
= 30µA 186 233 280 ns
I
ON
= 60µA 95 115 135 ns
t
ON(MIN)
Minimum On-Time I
ON
= 180µA 50 100 ns
t
OFF(MIN)
Minimum Off-Time I
ON
= 30µA 300 400 ns
V
SENSE(MAX)
Maximum Current Sense Threshold (Source) V
RNG
= 1V, V
FB
= V
REF/2
– 50mV ● 108 135 162 mV
V
PGND
– V
SW
V
RNG
= 0V, V
FB
= V
REF/2
– 50mV ● 76 95 114 mV
V
RNG
= INTV
CC
, V
FB
= V
REF/2
– 50mV ● 148 185 222 mV
V
SENSE(MIN)
Minimum Current Sense Threshold (Sink) V
RNG
= 1V, V
FB
= V
REF/2
+ 50mV ● –140 –165 –190 mV
V
PGND
– V
SW
V
RNG
= 0V, V
FB
= V
REF/2
+ 50mV ● –97 –115 –133 mV
V
RNG
= INTV
CC
, V
FB
= V
REF/2
+ 50mV ● –200 –235 –270 mV
∆V
FB(OV)
Output Overvoltage Fault Threshold 8 10 12 %
∆V
FB(UV)
Output Undervoltage Fault Threshold –25 %
V
RUN/SS(ON)
RUN Pin Start Threshold ● 0.8 1.5 2 V
V
RUN/SS(LE)
RUN Pin Latchoff Enable Threshold RUN/SS Pin Rising 4 4.5 V
V
RUN/SS(LT)
RUN Pin Latchoff Threshold RUN/SS Pin Falling 3.5 4.2 V
I
RUN/SS(C)
Soft-Start Charge Current –0.5 –1.2 –3 µA
I
RUN/SS(D)
Soft-Start Discharge Current 0.8 1.8 3 µA