U2894B Datasheet, PDF (8/16 Pages) TEMIC Semiconductors – Modulation PLL for GSM, DCS and PCS Systems

U2894B
VS2
4
CPC
I
I_CPCK /4
1.1 V
Ref
up
Ref
GND
2230 Ω
2
2
n ^{= Transistor with an emitter area–factor of “n”}
Figure 7. Charge pump
VS2
VSP
4
4
down
2I
CPO
2I
GNDP
14555
ND/RD
NND/NRD
2 kΩ 2 kΩ
V_{Ref_div}
PU, PUMIX
20 kΩ
30 kΩ
Figure 9. Power-up
GND
14557
Figure 8. Dividers
GND
14556
VS2
MC
GND
2x
60 µA
N–divider
Logic R–divider
MUX
14898
Figure 10. Mode control
C (U) ^â‰
2.5 pF @ 2 V
C (U) is a non-linear junction capacitance
14559
Figure 11. ESD-protection diodes
8 (16)
Rev. A4, 30-Sep-98