CSP1027 Datasheet, PDF (39/64 Pages) Agere Systems – CSP1027 Voice Band Codec for Cellular Handset and Modem Applications

Data Sheet
December 1999
CSP1027 Voice Band Codec for
Cellular Handset and Modem Applications
7 Application Information (continued)
0
–20 _CEXT ₌
–40 ^{50 pF}
–60
–80
–100
–120
–140
–160
CEXT =
20 pF
CEXT =
10 pF
–180
–200
5 10 15 20 25 30 35 40 45 50
FREQUENCY (MHz)
PROC
5.0 V
3.0 V
5.0 V
3.0 V
5.0 V
3.0 V
CEXT
10 pF
10 pF
20 pF
20 pF
50 pF
50 pF
XLO
XHI
C0
C1
C2
Z(ω)
C1 = C2 = CEXT
C0 = PARASITIC CAPACITANCE OF
CRYSTAL (7 pF MAXIMUM)
5-7610 (F)
Figure 31. Negative Resistance of Crystal Oscillator Circuit, VDD = 4.75 V
0
–20 CEXT =
50 pF
–40
–60
–80
–100
–120
–140
–160
CEXT =
20 pF
CEXT =
10 pF
–180
–200
6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40
FREQUENCY (MHz)
PROC
5.0 V
3.0 V
5.0 V
3.0 V
5.0 V
3.0 V
CEXT
10 pF
10 pF
20 pF
20 pF
50 pF
50 pF
XLO
XHI
C0
C1
C2
Z(ω)
C1 = C2 = CEXT
C0 = PARASITIC CAPACITANCE OF
CRYSTAL (7 pF MAXIMUM)
5-7611 (F)
Figure 32. Negative Resistance of Crystal Oscillator Circuit, VDD = 3.0 V
Lucent Technologies Inc.
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