3
LTC1159
LTC1159-3.3/LTC1159-5
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
V
CC
Internal Regulator Voltage V
IN
= 12V to 40V, EXTV
CC
= 0V, I
CC
= 10mA ● 4.25 4.5 4.75 V
V
IN
– V
CC
V
CC
Dropout Voltage V
IN
= 4V, EXTV
CC
= Open, I
CC
= 10mA 300 400 mV
V
EXT
– V
CC
EXTV
CC
Switch Drop V
IN
= 12V, EXTV
CC
= 5V, I
SWITCH
= 10mA 250 350 mV
V
P-GATE
– V
IN
P-Gate to Source Voltage (Off) V
IN
= 12V –0.2 0 V
V
IN
= 40V –0.2 0 V
V
SENSE
+
– Current Sense Threshold Voltage
V
SENSE
–
LTC1159 V
SENSE
–
= 5V, V
FB
= 1.32V (Forced) 25 mV
V
SENSE
–
= 5V, V
FB
= 1.15V (Forced) ● 130 150 170 mV
LTC1159-3.3 V
SENSE
–
= 3.4V (Forced) 25 mV
V
SENSE
–
= 3.1V (Forced) ● 130 150 170 mV
LTC1159-5 V
SENSE
–
= 5.2V (Forced) 25 mV
V
SENSE
–
= 4.7V (Forced) ● 130 150 170 mV
V
SNDN1
SHDN1 Threshold
LTC1159CG, LTC1159-3.3, LTC1159-5 0.5 0.8 2 V
V
SHDN2
SHDN2 Threshold 0.8 1.4 2 V
I
SHDN2
Shutdown 2 Input Current V
SHDN2
= 5V 12 20 µA
I
CT
C
T
Pin Discharge Current V
OUT
in Regulation 50 70 90 µA
V
OUT
= 0V 2 10 µA
t
OFF
Off-Time (Note 5) C
T
= 390pF, I
LOAD
= 700mA, V
IN
= 10V 4 5 6 µs
t
r
, t
f
Driver Output Transition Times C
L
= 3000pF (Pins P-Drive and N-Gate), V
IN
= 6V 100 200 ns
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
V
FB
Feedback Voltage (LTC1159 Only) 1.2 1.25 1.3 V
V
OUT
Regulated Output Voltage V
IN
= 9V
LTC1159-3.3 I
LOAD
= 700mA 3.17 3.30 3.43 V
LTC1159-5 I
LOAD
= 700mA 4.85 5.05 5.25 V
I
IN
V
IN
Pin Current (Note 4)
Normal V
IN
= 12V, EXTV
CC
= 5V 200 µA
V
IN
= 40V, EXTV
CC
= 5V 300 µA
Shutdown V
IN
= 12V, V
SHDN2
= 2V 15 µA
V
IN
= 40V, V
SHDN2
= 2V 25 µA
I
EXTVCC
EXTV
CC
Pin Current (Note 4) EXTV
CC
= 5V, Sleep Mode 250 µA
V
CC
Internal Regulator Voltage V
IN
= 12V to 40V, EXTV
CC
= 0V, I
CC
= 10mA 4.5 V
V
SENSE
+
– Current Sense Threshold Voltage Low Threshold (Forced) 25 mV
V
SENSE
–
High Threshold (Forced) 125 150 175 mV
V
SHDN2
SHDN2 Threshold 0.8 1.4 2 V
t
OFF
Off-Time (Note 5) C
T
= 390pF, I
LOAD
= 700mA, V
IN
= 10V 3.5 5 6.5 µs
–40°C ≤ T
A
≤ 85°C (Note 6)
Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2: T
J
is calculated from the ambient temperature T
A
and power
dissipation P
D
according to the following formulas:
LTC1159CG, LTC1159CG-3.3, LTC1159CG-5: T
J
= T
A
+ (P
D
• 135°C/W)
LTC1159CN, LTC1159CN-3.3, LTC1159CN-5: T
J
= T
A
+ (P
D
• 80°C/W)
LTC1159CS, LTC1159CS-3.3, LTC1159CS-5: T
J
= T
A
+ (P
D
• 110°C/W)
Note 3: On LTC1159 versions which have a SHDN1 pin, it must be at
ground potential for testing.
Note 4: The LTC1159 V
IN
and EXTV
CC
current measurements exclude
MOSFET driver currents. When V
CC
power is derived from the output via
EXTV
CC
, the input current increases by (I
GATECHG
• Duty Cycle)/(Efficiency).
See Typical Performance Characteristics and Applications Information.
Note 5: In applications where R
SENSE
is placed at ground potential, the off-
time increases approximately 40%.
E
LECTR
IC
AL C CHARA TERIST
ICS
The ● denotes specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
IN
= 12V, V
SHDN1
= 0V (Note 3), unless otherwise noted.
