AN938 Datasheet, PDF (5/33 Pages) STMicroelectronics – The L4973 family is a 3.5 A monolithic DC-DC converter

AN938
1
Description
Description
For a better understanding of the device and operation, a short description of the main
building blocks is given in Figure 2 and 3 with packaging options and complete block
diagram.
Figure 2. Pin out - power DIP18 and SO20 packages
OSC
OUT
OUT
GND
GND
GND
V_CC
V_CC
BOOT
1
18
2
17
3
16
4
15
5
14
6
13
7
12
8
11
9
10
D94IN162A
SYNC
SS
V5.1
GND
GND
GND
VFB
COMP
INH
Po werd ip (12+3+3)
OSC
OUT
OUT
GND
GND
GND
GND
V_CC
V_CC
BOOT
1
20
2
19
3
18
4
17
5
16
6
15
7
14
8
13
9
12
10
11
D94IN163A
SO20 (12+4+4)
SYNC
SS
V5.1
GND
GND
GND
GND
VFB
COMP
INH
AM03484v1
Figure 3. Device block diagram
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Doc ID 5410 Rev 10
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