U3600BM_05 Datasheet, PDF (20/44 Pages) ATMEL Corporation – Single-chip Cordless Telephone IC

9. Channel Frequencies, Dividers and Country Settings
To meet all requirements of various countries – France (F), Spain (E), Netherlands (NL), USA,
Portugal (P), Taiwan, New Zealand and Korea – and modes – base (b), handset (h) – several
bits have to be set which do not change for the different channels. These settings are called
country settings.
• The country-setting bits contain:
• Rough adjustments for 2 VCOs
• Setting three integer divider in the mixer PLL and modulator PLL
• Conversion gain adjustment of mixer PLL
• Modulator gain
• Setting of the pulling direction of PLL2 (value dependent, if TX frequency is higher or lower
than LO frequency)
• Demodulator gain
Name Register
RA1[1:0]
RA2[1:0]
D1[1:0]
D20
M12
D3[1:0]
KV[3:1]
GMOD[1:0]
IMIXI
DR1[1:0]
FRMT
GDEM
Function
Rough adjust VCO1
Rough adjust VCO2
Integer divider D1
Integer divider D2
Integer divider M12
Integer divider D3
Conversion gain VCO2
Modulator gain
Reverse inputs of PC of
PLL
Additional divider M for
reference frequency f_Ref1
Frequency range
Mixer T
Demodulator gain
Notes
00: is the highest frequency
00: is the highest frequency
Division by 2, 4, 6, 8
Division by 6, 8
Doubles reference frequency
of PLL2 when set to “1”
Division by 1, 2, 4
00: gain minimal
0: if fVCO2 lower than fVCO3
“0” means no reduction, >0
only necessary in E, NL,
Portugal
0: output frequency < 5 MHz
0: high gain
1: low gain
Note:
Setting the fractional dividers:
For N, Q_M, send the binary equivalent of the numbers given below.
For P_M (integer part of modulator PLL), send the D2 complement (16 – P_M)
i.e., Fb1 (P_M = 7, Q_M = 159 => integer: send 16 – P_M = 9, fractional: send 159)
Number of
Positions
3
4
4
2
2
3
6
3
2
4
2
2
20 U3600BM
4516D–CT0–10/05