AN1139 STMicroelectronics, AN1139 Datasheet - Page 55

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

Figure 37c. Mathcad Analisys of the Spindle Speed Control Loop
Close Loop Gain
arg(
20 log(
.
C( ) n
)
C( ) n
.
C( ) n
360
. 2
)
180
135
135
180
90
45
45
90
50
40
30
20
10
0
10
20
30
40
50
0
0.01
1 H( ) n
0.01
H( ) n
0.1
0.1
CLOSE LOOP MAGNITUDE RESPONSE in DB
CLOSE LOOP PHASE RESPONSE in degrees
1
1
f( ) n
f( ) n
10
10
AN1139 APPLICATION NOTE
100
100
1000
1000
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