LTC1735
ABSOLUTE AXI U RATI GS (Note 1)
Input Supply Voltage (VIN).........................36V to – 0.3V
Topside Driver Supply Voltage (BOOST)....42V to – 0.3V
Switch Voltage (SW) ....................................36V to – 5V
EXTVCC Voltage ...........................................7V to – 0.3V
Boosted Driver Voltage (BOOST – SW) .......7V to – 0.3V
SENSE+, SENSE– Voltages .......... 1.1 (INTVCC) to – 0.3V
FCB Voltage ............................(INTVCC + 0.3V) to – 0.3V
ITH, VOSENSE Voltages ...............................2.7V to – 0.3V
RUN/SS, PGOOD (LTC1735F Only)
Voltages .......................................................7V to – 0.3V
Peak Driver Output Current <10µs (TG, BG) .............. 3A
INTVCC Output Current ......................................... 50mA
Operating Ambient Temperature Range
LTC1735C ............................................... 0°C to 85°C
LTC1735I/LTC1735E (Note 8) ............ – 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
UW U
PACKAGE/ORDER I FOR ATIO
TOP VIEW
COSC 1
RUN/SS 2
ITH 3
FCB 4
SGND 5
VOSENSE 6
SENSE– 7
SENSE+ 8
16 TG
15 BOOST
14 SW
13 VIN
12 INTVCC
11 BG
10 PGND
9 EXTVCC
GN PACKAGE
16-LEAD NARROW
PLASTIC SSOP
S PACKAGE
16-LEAD PLASTIC SO
TJMAX = 125°C, θJA = 130°C/W (GN)
TJMAX = 125°C, θJA = 110°C/W (S)
ORDER PART
NUMBER
LTC1735CGN
LTC1735CS
LTC1735IGN
LTC1735IS
LTC1735EGN
GN PART MARKING
1735
1735I
1735E
Consult LTC marketing for parts specified with wider operating temperature ranges.
TOP VIEW
NC 1
COSC 2
RUN/SS 3
ITH 4
FCB 5
SGND 6
VOSENSE 7
PGOOD 8
SENSE– 9
SENSE+ 10
20 NC
19 TG
18 BOOST
17 SW
16 VIN
15 INTVCC
14 BG
13 PGND
12 EXTVCC
11 NC
F PACKAGE
20-LEAD PLASTIC TSSOP
TJMAX = 125°C, θJA = 110°C/W
ORDER PART
NUMBER
LTC1735CF
LTC1735IF
ELECTRICAL CHARACTERISTICS The q denotes specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. VIN = 15V, VRUN/SS = 5V unless otherwise noted.
SYMBOL
PARAMETER
CONDITIONS
MIN TYP MAX
Main Control Loop
IVOSENSE
VOSENSE
∆VLINEREG
∆VLOADREG
Feedback Current
Feedback Voltage
Reference Voltage Line Regulation
Output Voltage Load Regulation
DF Max
Maximum Duty Factor
(Note 3)
(Note 3)
VIN = 3.6V to 30V (Note 3)
(Note 3)
Measured in Servo Loop; VITH = 0.7V
Measured in Servo Loop; VITH = 2V
In Dropout
q 0.792
–4
0.8
0.001
– 25
0.808
0.02
q
q
98
0.1
0.3
– 0.1 – 0.3
99.4
gm
Transconductance Amplifier gm
VFCB
Forced Continuous Threshold
IFCB
Forced Continuous Current
VFCB = 0.85V
1.3
q 0.76
0.8
0.84
– 0.17 – 0.3
2
UNITS
nA
V
%/V
%
%
%
mmho
V
µA
1735fc