LTC1983-3/LTC1983-5
10
1983fc
For more information www.linear.com/LTC1983-3
operaTion
(Refer to Block Diagram)
in the low I
Q
mode, it is necessary to switch the part in
and out of shutdown at the minimum allowable frequency
(refer to Figure 3) for a given output load.
General Layout Considerations
Due to the high switching frequency and high transient
currents produced by the LTC1983, careful board layout
is a must. A clean board layout using a ground plane and
short connections to all capacitors will improve perfor
-
mance and
ensure proper regulation under all conditions
(refer to Figures
4a and 4b). You will not get advertised
performance with careless layout.
OUTPUT CURRENT (µA)
1
10
100
1000
MAXIMUM SHDN OFF TIME (ms)
1000
1983 F03b
1 10 100
SHDN ON PULSE WIDTH = 200µs
C
OUT
= 10µF
1 V
IN
2 V
OUT
3 C
+
SHDN 6
GND 5
C
–
4
C
OUT
C
FLY
V
IN
: 2.3V TO 5.5V
V
OUT
1983 F04a
C
IN
1 V
IN
2 V
OUT
3 C
+
SHDN 6
GND 5
C
–
4
C
IN
C
OUT
C
FLY
V
OUT
1983 F04b
BOTTOM LAYER TOP LAYER
Figure 3
Figure 4a. Recommended Component
Placement for a Single Layer Board
Figure 4b. Recommended Component
Placement for a Double Layer Board
