U2893B Datasheet, PDF (7/14 Pages) TEMIC Semiconductors – Modulation PLL for GSM, DCS and PCS Systems

U2893B
Mode Selection
The device can be programmed to different modes via an external resistor (including short, open) connected between
Pin MC and VS2. The mode selection controls the N-, R-divider ratios, and the polarity of the charge pump current.
Mode Selection
Mode Resistance between Pin MC
and Pin VS2
1
0 (<50 W)
2
W 2.7 k (±5%)
3
10 kW (±5%)
4
36 kW (±5%)
5
R (>1 MW)
1) _{Frequencies referred to PFD input!}
N-Divider
3:1
2:1
2:1
3:1
3:1
R-Divider
5:1
5:1
6:1
6:1
6:1
CPO Current Polarity Application
f_N < f_R ¹⁾ f_N < f_R ¹⁾
Sink
Source
Source
Source
Sink
Source
Sink
Sink
Sink
Source
GSM
PCS
DCS
GSM
GSM
Equivalent Circuits at the IC’s Pins
NI,IN,^{ÏÏÏÏÏÏÏQQ ÏÏÏÏÏÏÏ}
ÏÏÏÏ₂₂₃₀
ÏÏ _MDLO
ÏÏÏÏÏÏÏÏ _{Vref_input}
Vbias_MDLO
2230
250
Vref_MDLO
30p
Baseband input
NRRFF^{ÏÏÏÏÏÏ}
1k Vbias_RF
890
890
Vref_RF
LO input
Figure 5. I/Q modulator
1k
Vbias_LO
ÏÏ _1.6k
1.6k
Ï _MIXLO
ÏÏ _40p
Ï ^Vref_LO
RF input
LO input
Output
Figure 6. Mixer
Vref_output
Output
Ï _VS1
ÏÏ _MDO
Ï _NMDO
ÏÏÏÏÏÏÏÏ _GND
Ï_VS3
ÏÏÏÏÏ_6.3
ÏMIXO
ÏÏÏÏ_GND
TELEFUNKEN Semiconductors
7 (14)
Rev. A1, 29-Jan-97
Preliminary Information