LTC1159/LTC1159-3.3/LTC1159-5
ELECTRICAL CHARACTERISTICS
SYMBOL
V
EXT
– V
CC
V
P-GATE
– V
IN
V
SENSE +
–
V
SENSE –
PARAMETER
EXTV
CC
Switch Drop
P-Gate to Source Voltage (Off)
Current Sense Threshold Voltage
LTC1159
LTC1159-3.3
LTC1159-5
V
SNDN1
V
SHDN2
I
SHDN2
I
CT
t
OFF
t
r
, t
f
SHDN1 Threshold
LTC1159CG, LTC1159-3.3, LTC1159-5
SHDN2 Threshold
Shutdown 2 Input Current
C
T
Pin Discharge Current
Off-Time (Note 4)
Driver Output Transition Times
V
IN
= 12V
V
IN
= 40V
T
A
= 25°C, V
IN
= 12V, V
SHDN1
= 0V (Note 2), unless otherwise noted.
MIN
– 0.2
– 0.2
TYP
250
0
0
25
150
25
150
25
150
0.8
1.4
12
50
4
70
2
5
100
MAX
350
UNITS
mV
V
V
mV
mV
mV
mV
mV
mV
V
V
µA
µA
µA
µs
ns
CONDITIONS
V
IN
= 12V, EXTV
CC
= 5V, I
SWITCH
= 10mA
V
SENSE –
= 5V, V
FB
= 1.32V (Forced)
V
SENSE –
= 5V, V
FB
= 1.15V (Forced)
V
SENSE –
= 3.4V (Forced)
V
SENSE –
= 3.1V (Forced)
V
SENSE –
= 5.2V (Forced)
V
SENSE –
= 4.7V (Forced)
q
q
q
130
130
130
0.6
0.8
170
170
170
2
2
20
90
10
6
200
V
SHDN2
= 5V
V
OUT
in Regulation
V
OUT
= 0V
C
T
= 390pF, I
LOAD
= 700mA, V
IN
= 10V
C
L
= 3000pF (Pins P-Drive and N-Gate), V
IN
= 6V
– 40°C
≤
T
A
≤
85°C (Note 5)
SYMBOL
V
FB
V
OUT
PARAMETER
Feedback Voltage (LTC1159 Only)
Regulated Output Voltage
LTC1159-3.3
LTC1159-5
V
IN
Pin Current (Note 3)
Normal
Shutdown
I
EXTVCC
V
CC
V
SENSE +
–
V
SENSE –
V
SHDN2
t
OFF
EXTV
CC
Pin Current (Note 3)
Internal Regulator Voltage
Current Sense Threshold Voltage
SHDN2 Threshold
Off-Time (Note 4)
C
T
= 390pF, I
LOAD
= 700mA, V
IN
= 10V
V
IN
= 9V
I
LOAD
= 700mA
I
LOAD
= 700mA
V
IN
= 12V, EXTV
CC
= 5V
V
IN
= 40V, EXTV
CC
= 5V
V
IN
= 12V, V
SHDN2
= 2V
V
IN
= 40V, V
SHDN2
= 2V
EXTV
CC
= 5V, Sleep Mode
V
IN
= 12V to 40V, EXTV
CC
= 0V, I
CC
= 10mA
Low Threshold (Forced)
High Threshold (Forced)
CONDITIONS
MIN
1.2
3.17
4.85
TYP
1.25
3.30
5.05
200
300
15
25
250
4.5
25
150
1.4
5
MAX
1.3
3.43
5.25
UNITS
V
V
V
µA
µA
µA
µA
µA
V
mV
mV
V
µs
I
IN
125
0.8
3.5
175
2
6.5
The
q
denotes specifications which apply over the full operating
temperature range.
Note 1:
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 2:
On LTC1159 versions which have a SHDN1 pin, it must be at
ground potential for testing.
Note 3:
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 4:
In applications where R
SENSE
is placed at ground potential, the off-
time increases approximately 40%.
Note 5:
The LTC1159, LTC1159-3.3, and LTC1159-5 are not tested and
not quality assurance sampled at – 40°C and 85°C. These specifications
are guaranteed by design and/or correlation.
Note 6:
The logic-level power MOSFETs shown in Figure 1 are rated for
V
DS(MAX)
= 30V. For operation at V
IN
> 30V, use standard threshold
MOSFETs with EXTV
CC
powered from a 12V supply. See Applications
Information.
3
LINER [ LINEAR TECHNOLOGY ]
