Datasheet

3
LTC1751/LTC1751-3.3/LTC1751-5
The ● denotes specifications which apply over the full specified
temperature range, otherwise specifications are at T
A
= 25°C. C
FLY
= 1µF, C
IN
= 10µF, C
OUT
= 10µF unless otherwise noted.
ELECTRICAL CHARACTERISTICS
Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2: Based on long term current density limitations.
Note 3: The LTC1751EMS8-X is guaranteed to meet performance
specifications from 0°C to 70°C. Specifications over the –40°C to 85°C
operating temperature range are assured by design, characterization and
correlation with statistical process controls.
Note 4: The no load input current will be approximately I
CC
plus twice the
standing current in the resistive output divider.
Note 5: R
OUT
≡ (2V
IN
– V
OUT
)/I
OUT
.
Note 6: See Figure 2.
TYPICAL PERFOR A CE CHARACTERISTICS
UW
Output Voltage vs Load Current
LOAD CURRENT (mA)
0
3.20
OUTPUT VOLTAGE (V)
3.25
3.30
3.35
3.40
25 50 75 100
1751 G01
125 150
T
A
= 25°C
C
FLY
= 1µF
V
IN
= 2V
V
IN
= 2.5V
INPUT VOLTAGE (V)
2.0
OUTPUT VOLTAGE (V)
3.30
3.35
4.0
1751 G02
3.25
3.20
2.5
3.0
3.5
4.5
3.40
I
OUT
= 40mA
C
FLY
= 1µF
C
OUT
= 10µF
T
A
= –40°C
T
A
= 85°C
T
A
= 25°C
INPUT VOLTAGE (V)
2.0
SUPPLY CURRENT (µA)
20
30
4.0
1751 G03
10
0
2.5
3.0
3.5
4.5
40
I
OUT
= 0mA
C
FLY
= 1µF
V
SHDN
= V
IN
T
A
= 85°C
T
A
= 25°C
T
A
= –40°C
Output Voltage vs Input Voltage
No Load Supply Current
vs Input Voltage
(LTC1751-3.3)
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
LTC1751-3.3/LTC1751-5
UVL PGOOD Undervoltage Low Threshold Relative to Regulated V
OUT
(Note 6) ● –11 –7 –3 %
UVH PGOOD Undervoltage High Threshold Relative to Regulated V
OUT
(Note 6) ● –8 –4.5 –2 %
V
OL
PGOOD Low Output Voltage I
PGOOD
= –500µA ● 0.4 V
I
OH
PGOOD High Output Leakage V
PGOOD
= 5.5V ● 1 µA
LTC1751/LTC1751-3.3/LTC1751-5
I
SHDN
Shutdown Supply Current V
IN
≤ 3.6V, V
OUT
= 0V, V
SHDN
= 0V ● 0.01 2 µA
3.6V < V
IN
, V
OUT
= 0V, V
SHDN
= 0V ● 5 µA
V
IH
SHDN Input Threshold (High) ● 1.5 V
V
IL
SHDN Input Threshold (Low) ● 0.3 V
I
IH
SHDN Input Current (High) SHDN = V
IN
● –1 1 µA
I
IL
SHDN Input Current (Low) SHDN = 0V ● –1 1 µA
t
r
V
OUT
Rise Time V
IN
= 3V, I
OUT
= 0mA, 10% to 90% (Note 6) 0.6ms/nF • C
SS
sec
f
OSC
Switching Frequency Oscillator Free Running 800 kHz