MIC2560 Micrel Semiconductor, MIC2560 Datasheet - Page 8

• Manufacturer Part Number: MIC2560
• Description: PCMCIA Card Socket VCC and VPP Switching Matrix
• Manufacturer: Micrel Semiconductor

MIC2560
High Current V
+12V Supply
Figure 5 shows the MIC2560 with V
by a simple charge pump. This enables the system designer
to achieve full V
is often helpful in battery powered systems that only provide
+12V when it is needed. These on-demand +12V supplies
generally have a quiescent current draw of a few milliam-
MIC2560
Figure 5. Circuit for generating bias drive for the V
CC
performance without a +12V supply, which
CC
Operation Without a
Drive Enable
CC
+5V
switch bias provided
0.01µF
2
3
4
5
6
7
8
MIC2560
4.7k
16
15
14
13
12
11
10
9
1N914
8
0.1µF
peres, which is far more than the microamperes used by the
MIC2560. The charge pump of figure 5 provides this low
current, using about 100 A when enabled. When V
12V is selected, however, the on-demand V
must be used, as this charge pump cannot deliver the current
required for Flash memory programming. The Schottky diode
may not be necessary, depending on the configuration of the
on-demand +12V generator and whether any other loads are
on this line.
CC
switches when +12V is not readily available.
1N914
0.02µF
Switched V PP IN
(Optional Schottky)
November 1999
PP
generator
PP OUT
Micrel
=