AN1139 STMicroelectronics, AN1139 Datasheet - Page 53

• Manufacturer Part Number: AN1139
• Description: L6254 - L6268 - L6269 12V DISK DRIVE POWER COMBO IC
• Manufacturer: STMicroelectronics

Figure 37a. Mathcad Analisys of the Spindle Speed Control Loop
VELOCITY LOOP TRANSFER FUNCTION :
i
f( ) n
S( ) n
n
Sz
Sp
Kc
Zfilter( ) n
, 2 1.99 3
Rc Cc1
Rc
Cc1 Cc2
1
10
2 i
.
1
.
. .
Cc1 Cc2
n
Cc1 Cc2
1
1
.
Kc
..
10
.
.
n
S( ) n
S( ) n
.
Sz
S( ) n
Sp
Filter zero
Filter pole
1
1
fz
fp
AN1139 APPLICATION NOTE
. 2
. 2
Sz
Sp
fz 0.37
fp
=
=
4.071
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