LTC3108
3
3108fc
For more information www.linear.com/LTC3108
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2: The LTC3108 is tested under pulsed load conditions such that T
J
≈
T
A
. The LTC3108E is guaranteed to meet specifications from 0°C to 85°C
junction temperature. Specifications over the –40°C to 125°C operating
junction temperature range are assured by design, characterization and
correlation with statistical process controls. The LTC3108I is guaranteed
over the full –40°C to 125°C operating junction temperature range.
Note that the maximum ambient temperature is determined by specific
operating conditions in conjunction with board layout, the rated thermal
package thermal resistance and other environmental factors. The junction
temperature (T
J
) is calculated from the ambient temperature (T
A
) and
power dissipation (P
D
) according to the formula: T
J
= T
A
+ (P
D
• θ
JA
°C/W),
where θ
JA
is the package thermal impedance.
Note 3: Specification is guaranteed by design and not 100% tested in
production.
Note 4: Failure to solder the exposed backside of the package to the PC
board ground plane will result in a thermal resistance much higher than
43°C/W.
Note 5: The absolute maximum rating is a DC rating. Under certain
conditions in the applications shown, the peak AC voltage on the C2 pin
may exceed ±8V. This behavior is normal and acceptable because the
current into the pin is limited by the impedance of the coupling capacitor.
elecTrical characTerisTics
The l denotes the specifications which apply over the full operating
junction temperature range, otherwise specifications are for T
A
= 25°C (Note 2). VAUX = 5V, unless otherwise noted.
PARAMETER CONDITIONS MIN TYP MAX UNITS
Output Voltage VS1 = VS2 = GND
VS1 = VAUX, VS2 = GND
VS1 = GND, VS2 = VAUX
VS1 = VS2 = VAUX
l
l
l
l
2.30
3.234
4.018
4.90
2.350
3.300
4.100
5.000
2.40
3.366
4.182
5.10
V
V
V
V
V
OUT
Quiescent Current V
OUT
= 3.3V, V
OUT2_EN
= 0V 0.2 µA
VAUX Quiescent Current No Load, All Outputs Charged 6 9 µA
LDO Output Voltage 0.5mA Load
l
2.134 2.2 2.266 V
LDO Load Regulation For 0mA to 2mA Load 0.5 1 %
LDO Line Regulation For VAUX from 2.5V to 5V 0.05 0.2 %
LDO Dropout Voltage I
LDO
= 2mA
l
100 200 mV
LDO Current Limit V
LDO
= 0V
l
4 11 mA
V
OUT
Current Limit V
OUT
= 0V
l
2.8 4.5 7 mA
VSTORE Current Limit VSTORE = 0V
l
2.8 4.5 7 mA
VAUX Clamp Voltage Current into VAUX = 5mA
l
5 5.25 5.55 V
VSTORE Leakage Current VSTORE = 5V 0.1 0.3 µA
V
OUT2
Leakage Current V
OUT2
= 0V, V
OUT2_EN
= 0V 0.1 µA
VS1, VS2 Threshold Voltage
l
0.4 0.85 1.2 V
VS1, VS2 Input Current VS1 = VS2 = 5V 0.01 0.1 µA
PGOOD Threshold (Rising) Measured Relative to the V
OUT
Voltage –7.5 %
PGOOD Threshold (Falling) Measured Relative to the V
OUT
Voltage –9 %
PGOOD V
OL
Sink Current = 100µA 0.15 0.3 V
PGOOD V
OH
Source Current = 0 2.1 2.2 2.3 V
PGOOD Pull-Up Resistance 1 MΩ
V
OUT2_EN
Threshold Voltage V
OUT2_EN
Rising
l
0.4 1 1.3 V
V
OUT2_EN
Pull-Down Resistance 5 MΩ
V
OUT2
Turn-On Time 5 µs
V
OUT2
Turn-Off Time (Note 3) 0.15 µs
V
OUT2
Current Limit V
OUT
= 3.3V
l
0.15 0.3 0.45 A
V
OUT2
Current Limit Response Time (Note 3) 350 ns
V
OUT2
P-Channel MOSFET On-Resistance V
OUT
= 3.3V (Note 3) 1.3 Ω
N-Channel MOSFET On-Resistance C2 = 5V (Note 3) 0.5 Ω
