TDA7278 Datasheet, PDF (6/15 Pages) STMicroelectronics – HIGH-EFFICIENCY CD ACTUATOR DRIVER

TDA7278
Figure 2: Test Circuit
470pF
10µF
10µF
ST CAP 22
VREF (2) 38
VHIGH 11
VBAT
47µH
10
OUT
AUXIL.
STEP UP
SYNC
23
OSCILL
VBAT
4
30
37 35
V bg
43
ER
+
-
VHIGH
VBAT
DRIV
5 FL IN 1
S
-
Q
R
+
VHIGH
DRIV
VHIGH
DRIV
100µH
8 H IN 1
10µF
7 H OUT 1A
9 H OUT 1B
FOCUS
ACTUATOR
FEEDBAKC
&
COMPENSATION
NETWORK
(see fig.4)
INP 13
IRC 14
STEP LP
or
STEP DOWN
STRUCTURE
(see fig.3)
2µF
VCPU 15
OUT1 16
OUT2
17
SSCAP 12
VBG 18
100nF
24
ENABLE
VHIGH
DRIV
-
Vbg
+
VBAT
REFERENCE _Vbg
and
THERMAL
CRES 20
1µF
19
RESET
CONTROL
Vbg
VBAT
21
WD INP
BEMP 41
BLOW
40
VCPU
39
VCON
Vbg/2
+
-
Vbg/2
+
-
VHIGH
VBAT
DRIV
29 FL IN 3
S
ER
-
Q
R
+
VHIGH
+
DRIV
-
VHIGH
DRIV
100µH
26 H IN 3
10µF
27 H OUT 3A
25 H OUT 3B
TRACKING
ACTUATOR
VHIGH
VBAT
DRIV
3 FL IN 2
S
ER
-
Q
R
+
VHIGH
+
DRIV
-
VHIGH
DRIV
100µH
1 H IN 2
10µF
2 H OUT 2A
44 H OUT 2B
M ^SPINDLE
MOTOR
VHIGH
VBAT
DRIV
31 FL IN 4
S
ER
-
Q
R
+
VHIGH
+
DRIV
-
VHIGH
DRIV
100µH
33 H IN 4
10µF
32 H OUT 4A
34 H OUT 4B
M ^SLEDGE
MOTOR
6
28 42
36
GND
D94AU111A
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