Datasheet

3
LTC1147-3.3
LTC1147-5/LTC1147L
sn1147 1147fds
T
A
= 25°C, V
IN
= 10V, V
SHDN
= 0V, unless otherwise noted.
ELECTRICAL CHARACTERISTICS
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
V
5
– V
4
Current Sense Threshold Voltage (Note 6)
LTC1147-3.3, LTC1147L-3.3 V
SENSE
–
= V
OUT
+ 100mV (Forced) 25 mV
V
SENSE
–
= V
OUT
– 100mV (Forced) 130 150 170 mV
LTC1147–5 V
SENSE
–
= V
OUT
+ 100mV (Forced) 25 mV
V
SENSE
–
= V
OUT
– 100mV (Forced) 130 150 170 mV
LTC1147L V
SENSE
–
= 5V, V6 = V
OUT
/4 + 25mV (Forced) 25 mV
V
SENSE
–
= 5V, V6 = V
OUT
/4 – 25mV (Forced) 130 150 170 mV
V
6
SHDN Pin Threshold
LTC1147-3.3/LTC1147-5/LTC1147L-3.3 0.5 0.8 2 V
I
6
SHDN Pin Input Current
LTC1147-3.3/LTC1147-5/LTC1147L-3.3 0V < V
SHDN
< 8V, V
IN
= 16V 1.2 5 µA
I
2
C
T
Pin Discharge Current V
OUT
in Regulation, V
SENSE
–
= V
OUT
50 70 90 µA
V
OUT
= 0V 2 10 µA
t
OFF
Off-Time (Note 3) C
T
= 390pF, I
LOAD
= 700mA 4 5 6 µs
t
r
, t
f
Driver Output Transition Times C
L
= 3000pF (Pin 8), V
IN
= 6V 100 200 ns
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
V
6
Feedback Voltage (LTC1147L) V
IN
= 9V ● 1.20 1.25 1.30 V
V
OUT
Regulated Output Voltage V
IN
= 9V
LTC1147-3.3/LTC1147L-3.3 I
LOAD
= 700mA ● 3.17 3.33 3.43 V
LTC1147-5 I
LOAD
= 700mA ● 4.85 5.05 5.20 V
I
Q
Input DC Supply Current (Note 2) (Note 5)
LTC1147 Series
Normal Mode 4V < V
IN
< 12V 1.6 2.4 mA
Sleep Mode 4V < V
IN
< 12V 160 260 µA
Sleep Mode (LTC1147-5) 5V < V
IN
< 12V 160 260 µA
Shutdown V
SHDN
= 2.1V, 4V < V
IN
< 12V 10 22 µA
LTC1147L Series
Normal Mode 3.5V < V
IN
< 12V 1.6 2.4 mA
Sleep Mode 3.5V < V
IN
< 12V 160 260 µA
Shutdown (LTC1147L-3.3) V
SHDN
= 2.1V, 3.5V < V
IN
< 12V 10 22 µA
V
5
– V
4
Current Sense Threshold Voltage (Note 6)
LTC1147-3.3 V
SENSE
–
= V
OUT
+ 100mV (Forced) 25 mV
V
SENSE
–
= V
OUT
– 100mV (Forced) ● 125 150 185 mV
LTC1147-5 V
SENSE
–
= V
OUT
+ 100mV (Forced) 25 mV
V
SENSE
–
= V
OUT
– 100mV (Forced) ● 125 150 185 mV
LTC1147L V
SENSE
–
= 5V, 6V = V
OUT
/4 + 25mV (Forced) 25 mV
V
SENSE
–
= 5V, 6V = V
OUT
/4 – 25mV (Forced) 125 150 185 mV
V
6
SHDN Pin Threshold
LTC1147-3.3/LTC1147-5/LTC1147L-3.3 0V < V
SHDN
< 8V, V
IN
= 16V 0.5 0.8 2 V
t
OFF
Off-Time (Note 3) C
T
= 390pF, I
LOAD
= 700mA 3.8 5 6.5 µs
The ● denotes specifications which apply over the full specified
temperature range.
Note 1: T
J
is calculated from the ambient temperature T
A
and power
dissipation P
D
according to the following formulas:
LTC1147CN8-3.3/LTC1147CN8-5: T
J
= T
A
+ (P
D
)(110°C/W)
LTC1147LIS/LTC1147IS8/LTC1147LCS/
LTC1147CS8-3.3/LTC1147CS8-5: T
J
= T
A
+ (P
D
)(150°C/W)
Note 2: Dynamic supply current is higher due to the gate charge being
delivered at the switching frequency. See Applications Information.
Note 3: In applications where R
SENSE
is placed at ground potential, the off-
time increases approximately 40%.
Note 4: The LTC1147C is guaranteed to meet specified performance from
0°C to 70°C and is designed, characterized and expected to meet these
extended temperature limits, but is not tested at –40°C and 85°C. The
LTC1147I is guaranteed to meet the extended temperature limits.
Note 5: The LTC1147L/LTC1147L-3.3 allow operation to V
IN
= 3.5V.
Note 6: The LTC1147L is tested with external feedback resistors resulting
in a nominal output voltage of 2.5V.
–40°C ≤ T
A
≤ 85°C (Note 4), V
IN
= 10V, unless otherwise noted.