LM82CIMQA National Semiconductor, LM82CIMQA Datasheet - Page 6

• Manufacturer Part Number: LM82CIMQA
• Description: IC,SSOP,16PIN
• Manufacturer: National Semiconductor

Specifications of LM82CIMQA

• Rohs Compliant: NO

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Application Information
Low ESR Capacitor Manufacturers
Other Applications
Paralleling Devices
Any number of LM828s can be paralleled to reduce the out-
put resistance. Each device must have its own pumping ca-
pacitor C
shown in Figure 3. The composite output resistance is:
Cascading Devices
Cascading the LM828s is an easy way to produce a greater
negative voltage (e.g. A two-stage cascade circuit is shown
in Figure 4).
If n is the integer representing the number of devices cas-
caded, the unloaded output voltage V
tive output resistance is equal to the weighted sum of each
individual device:
Murata
Taiyo Yuden
Tokin
1
Manufacturer
R
, while only one output capacitor C
out
= nR
out_1
+ n/2 R
FIGURE 3. Lowering Output Resistance by Paralleling Devices
FIGURE 4. Increasing Output Voltage by Cascading Devices
out_2
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out
+ ... + R
is (-nV
Phone
(Continued)
out
out_n
in
is needed as
). The effec-
Ceramic chip capacitors
Ceramic chip capacitors
Ceramic chip capacitors
(Continued)
6
This can be seen by first assuming that each device is 100
percent efficient. Since the output voltage is different on
each device the output current is as well. Each cascaded de-
vice sees less current at the output than the previous so the
R
the number of n is practically limited since the increasing of
n significantly reduces the efficiency, and increases the out-
put resistance and output voltage ripple.
OUT
voltage drop is lower in each device added. Note that,
Capacitor Type
DS100137-9
DS100137-10