LTC114 4
12
1144fa
For more information www.linear.com/LTC1144
LINEAR TECHNOLOGY CORPORATION 1994
LT 0414 REV A • PRINTED IN USA
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900
●
FAX: (408) 434-0507
●
www.linear.com/LTC1144
relaTeD parTs
Typical applicaTion
PART NUMBER DESCRIPTION COMMENTS
LTC1054 15V, 100mA Inverting Charge Pump V
IN
= 3.5V to 15V, V
OUT(MAX)
= ±15V, I
Q
= 2.5mA, I
SD
= <1µA, DIP-8,
S0-8 Packages
LTC1046 6V, 100mA Inverting Charge Pump V
IN
= 1.5V to 6V, V
OUT(MAX)
= 3V, I
Q
= 200µA, I
SD
= <1µA, SO-8 Package
LT
®
3463/
LT3463A
250mA (I
SW
), Boost/Inverter Dual, Micropower
DC/DC Converter with Integrated Schottky Diodes
V
IN
= 2.4V to 15V, V
OUT(MAX)
= ±40V, I
Q
= 40µA, I
SD
= <1µA, DFN Package
LT1615/
LT1615-1
300mA/80mA I
SW
, Constant Off-Time, High Efficiency
Step-Up DC/DC Converter
V
IN
= 1.2V to 15V, V
OUT(MAX)
= 34V, I
Q
= 20µA, I
SD
= <1µA, ThinSOT Package
LT3467/
LT3467A
1.1A (I
SW
), 1.3MHz/2.1MHz, High Efficiency Step-Up
DC/DC Converter with Integrated Soft-Start
V
IN
= 2.4V to 16V, V
OUT(MAX)
= 40V, I
Q
= 1.2mA, I
SD
= <1µA, ThinSOT Package
LT1931/
LT1931A
1A (I
SW
), 1.2MHz/2.2MHz High Efficiency Inverting
DC/DC Converter
V
IN
= 2.6V to 16V, V
OUT(MAX)
= 34V, I
Q
= 4.2mA/5.5mA, I
SD
= <1µA,
ThinSOT Package
Regulated –5V Output Voltage
Figure 12 shows a regulated –5V output with a 9V input.
With a 0mA to 5mA load current, the R
OUT
is below 20Ω.
Paralleling for Lower Output Resistance
Additional
flexibility of the LTC1144 is shown in Figure 13.
Tw o LTC1144s are connected in parallel to provide a lower
effective output resistance. However, if the output resis
-
tance is dominated by 1/(f ×
C1), increasing the capacitor
size (C1) or increasing the frequency will be of more benefit
than the paralleling circuit shown.
Figure 12. A Regulated –5V Supply
Figure 13. Paralleling for Lower Output Resistance
1
2
3
4
8
7
6
5
+
+
100µF
–5V
36k
300k
LTC1144
V
OUT
= –(V
+
V
C1
C2
20µF
1
2
3
4
8
7
6
5
LTC1144
+
+
C1
10µF
1/4 CD4077*
* THE EXCLUSIVE NOR GATE
SYNCHRONIZES BOTH LTC1144s
TO MINIMIZE RIPPLE
1
2
3
4
8
7
6
5
LTC1144
+