Linear Technology LTC1736, Datasheet

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2
LTC1736
ABSOLUTE AXI U RATI GS
W W W U
PACKAGE/ORDER I FOR ATIO
U U W
(Note 1)
Input Supply Voltage (V
IN
).........................36V to – 0.3V
Topside Driver Supply Voltage (BOOST)....42V to – 0.3V
Switch Voltage (SW) ....................................36V to – 5V
EXTV
CC
, VIDV
CC
, (BOOST – SW) Voltages .. 7V to – 0.3V
SENSE
+
, SENSE
–
.......................... 1.1(INTV
CC
) to – 0.3V
FCB Voltage ............................(INTV
CC
+ 0.3V) to – 0.3V
I
TH
, V
OSENSE
, V
FB
Voltage .........................2.7V to – 0.3V
RUN/SS, VID0 to VID4, PGOOD Voltages ....7V to – 0.3V
Peak Driver Output Current <10
µ
s (TG, BG) .............. 3A
INTV
CC
Output Current ......................................... 50mA
Operating Ambient Temperature Range
LTC1736C ............................................... 0
°
C to 85
°
C
LTC1736I ............................................ – 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
Consult factory for Military grade parts.
T
JMAX
= 125
°
C,
θ
JA
= 110
°
C/W
1
2
3
4
5
6
7
8
9
10
11
12
TOP VIEW
G PACKAGE
24-LEAD PLASTIC SSOP
24
23
22
21
20
19
18
17
16
15
14
13
C
OSC
RUN/SS
I
TH
FCB
SGND
PGOOD
SENSE
–
SENSE
+
V
FB
V
OSENSE
VID0
VID1
TG
BOOST
SW
V
IN
INTV
CC
BG
PGND
EXTV
CC
VIDV
CC
VID4
VID3
VID2
ELECTRICAL CHARACTERISTICS
LTC1736CG
LTC1736IG
The
●
denotes specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25
°
C. V
IN
= 15V, V
RUN/SS
= 5V unless otherwise noted.
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
Main Control Loop
V
OSENSE
Output Voltage Set Accuracy (Note 3) See Table 1 ● 1 %
∆
V
LINEREG
Reference Voltage Line Regulation V
IN
= 3.6V to 30V (Note 3) 0.001 0.02 %/V
∆
V
LOADREG
Output Voltage Load Regulation (Note 3)
Measured in Servo Loop; V
ITH
= 0.7V ● 0.1 0.3 %
Measured in Servo Loop; V
ITH
= 2V ● – 0.1 – 0.3 %
g
m
Transconductance Amplifier g
m
1.3 mmho
V
FCB
Forced Continuous Threshold ● 0.76 0.8 0.84 V
I
FCB
Forced Continuous Current V
FCB
= 0.85V – 0.17 – 0.3
µ
A
V
OVL
Feedback Overvoltage Lockout ● 0.84 0.86 0.88 V
I
Q
Input DC Supply Current (Note 4)
Normal Mode 450
µ
A
Shutdown V
RUN/SS
= 0V 15 25
µ
A
V
RUN/SS
Run Pin Start Threshold V
RUN/SS
, Ramping Positive 1.0 1.5 1.9 V
V
RUN/SS
Run Pin Begin Latchoff Threshold V
RUN/SS
, Ramping Positive 4.1 4.5 V
I
RUN/SS
Soft-Start Charge Current V
RUN/SS
= 0V – 0.7 – 1.2
µ
A
I
SCL
RUN/SS Discharge Current Soft Short Condition, V
FB
= 0.5V, 0.5 2 4
µ
A
V
RUN/SS
= 4.5V
UVLO Undervoltage Lockout Measured at V
IN
Pin (V
IN
Ramping Down) ● 3.5 3.9 V
∆
V
SENSE(MAX)
Maximum Current Sense Threshold V
FB
= 0.7V ● 60 75 85 mV
I
SENSE
SENSE Pins Total Source Current V
SENSE
–
= V
SENSE
+
= 0.8V 60 80
µ
A
t
ON(MIN)
Minimum On-Time Tested with a Square Wave (Note 8) 160 200 ns
TG Transition Time: (Note 9)
TG t
r
Rise Time C
LOAD
= 3300pF 50 90 ns
TG t
f
Fall Time C
LOAD
= 3300pF 50 90 ns