LT1959
ABSOLUTE MAXIMUM RATINGS (Note 1)
Input Voltage .......................................................... 16V
BOOST Voltage ........................................................ 30V
BOOST Pin Above Input Voltage ............................. 15V
SHDN Pin Voltage ..................................................... 7V
FB Pin Voltage ....................................................... 3.5V
FB Pin Current ....................................................... 1mA
SYNC Pin Voltage ..................................................... 7V
Operating Junction Temperature Range
LT1959C ................................................ 0°C to 125°C
LT1959I ........................................... – 40°C to 125°C
Storage Temperature Range ................ – 65°C to 150°C
Lead Temperature (Soldering, 10 sec)................. 300°C
PACKAGE/ORDER INFORMATION
FRONT VIEW
7
FB
6
BOOST
TAB
5
VIN
IS
4
GND
GND
3
VSW
2
SHDN
1
VC
R PACKAGE
7-LEAD PLASTIC DD
TJMAX = 150°C, θJA = 30°C/W
WITH PACKAGE SOLDERED TO 0.5 SQUARE INCH
COPPER AREA OVER BACKSIDE GROUND PLANE OR
INTERNAL POWER PLANE. θJA CAN VARY FROM 20°C/W
TO > 40°C/W DEPENDING ON MOUNTING TECHNIQUES
ORDER PART
NUMBER
LT1959CR
LT1959IR
TOP VIEW
VIN 1
BOOST 2
FB 3
GND** 4
8 VSW
7 SYNC
6 SHDN
5 VC
S8 PACKAGE
8-LEAD PLASTIC SO
TJMAX = 150°C, θJA = 80°C/W
**WITH (FUSED GND) GROUND PIN
CONNECTED TO GROUND PLANE OR
LARGE LANDS
ORDER PART
NUMBER
LT1959CS8
LT1959IS8
S8 PART MARKING
1959
1959I
ELECTRICAL CHARACTERISTICS The q denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C, TJ = 25°C, VIN = 5V, VC = 1.5V, Boost = VIN + 5V, switch open, unless
otherwise noted.
PARAMETER
Feedback Voltage (Adjustable)
Reference Voltage Line Regulation
Feedback Input Bias Current
Error Amplifier Voltage Gain
Error Amplifier Transconductance
CONDITIONS
All Conditions
4.3V ≤ VIN ≤ 15V
(Note 2)
∆I (VC) = ±10µA
VC Pin to Switch Current Transconductance
Error Amplifier Source Current
Error Amplifier Sink Current
VC Pin Switching Threshold
VC Pin High Clamp
Switch Current Limit
Slope Compensation
VFB = 1.05V
VFB = 1.35V
Duty Cycle = 0
VC Open, VFB = 1.05V, DC ≤ 50%
DC = 80%
MIN TYP MAX
q 1.19 1.21 1.23
0.01 0.03
q –0.5 0 0.5
200 400
1500 2000 2700
q 1000
3100
5.3
q 140 225 320
q 140 225 320
0.9
2.1
q 4.5 6 8.5
0.8
UNITS
V
%/ V
µA
µMho
µMho
A/ V
µA
µA
V
V
A
A
2