TDA7326 Datasheet, PDF (10/16 Pages) STMicroelectronics – AM-FM RADIO FREQUENCY SYNTHESIZER

TDA7326
4.0 BIT ORGANIZATION OF THE BUS TRANSFER OPERATION
Loading registers for all bytes of the programmable counters and all control registers
0
1
PC7
PC6
LPF1/
LPF2
CURR1
SWM
DIR
AM
FM
1
0 PC5 PC4 PC3 PC2 PC1 PCO ⇒
®
1
1
SC5
(0)*
SC4
SC3
SC2 SC1 SC0
0
0
0
0
0 S_OUT CURR2 fref
Loading registers for all bytes of the programmable counters and all control registers
0
1
PC7
PC6
LPF2/
LPF1
CURR1
SWM
DIR
AM
FM
1
0 PC5 PC4 PC3 PC2 PC1 PCO ⇒
®
1
1
SC5
(0)*
SC4
SC3
SC2 SC1 SC0
Loading registers for 11 or 12 bits of the programmable counters
1
0 PC5 PC4 PC3 PC2 PC1 PC0 1
1
SC5
(0)*
SC4
SC3
SC2
SC1
SC0
Loading registers for 5 or 6 bits of the programmable counters
1
1
SC5
(0)*
SC4
SC3
SC2
SC1 SC0
Setting control register for loop filter selection charge pump current bit 1, mode AM/FM selection
0
1
X
X
LPF2/ CURR1 SWM/ AM
LPF1
DIR FM
Test mode inizialization (Test0 = Test1 = Test2 = 0)
0
0 TST0 TST1 TST2 SOUT CURR2 fREF
Setting control register for switch output pin 9, charge pump current bit 2, reference frequency select
0
0
0
0
0 SOUT CURR2 fREF
(*) This bit has to be ”0” for fREF = ”1” (fREF = 25kHz in FM mode or 2.5KHz AM swallow mode)
5.0 FREQUENCY PROGRAMMATION
5.1 AM/FM Computation Resume
FM SWALLOW MODE
fREF = 12.5KHz
FVCO = (64 ⋅ PC + SC + 64) ⋅ fREF
F_VCO = (DIV_VAL+ 64) ⋅ f_REF
swallow 6bit
f_REF = 25KHz
F_VCO = (32 ⋅ PC + SC + 32) ⋅ f_REF
FVCO = (DIV_VAL+ 32) ⋅ fREF
swallow 5bit (bit SC5 = 0)
where:
PC = Program Counter Value (PC7 to PC0)
SC = Swallow Counter Value (SC5 to SC0)
DIV_VAL = Divider Factor
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