LM2660/LM2661
Application Information
(Continued)
size capacitor usually has a higher ESR compared with a
bigger size capacitor of the same type. For lower ESR, use
ceramic capacitors.
DS012911-32
FIGURE 3. Output Source Resistance vs Oscillator Frequency
TABLE 3. Low ESR Capacitor Manufacturers
Manufacturer
Nichicon Corp.
AVX Corp.
Sprague
Sanyo
Phone
(708)-843-7500
(803)-448-9411
(207)-324-4140
(619)-661-6835
FAX
(708)-843-2798
(803)-448-1943
(207)-324-7223
(619)-661-1055
Capacitor Type
PL, PF series, through-hole aluminum electrolytic
TPS series, surface-mount tantalum
593D, 594D, 595D series, surface-mount tantalum
OS-CON series, through-hole aluminum electrolytic
Other Applications
PARALLELING DEVICES
Any number of LM2660s (or LM2661s) can be paralleled to reduce the output resistance. Each device must have its own pumping
capacitor C
1
, while only one output capacitor C
out
is needed as shown in
Figure 4.
The composite output resistance is:
DS012911-22
FIGURE 4. Lowering Output Resistance by Paralleling Devices
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