S1A0903X01-Q0R0 Samsung Electronics, S1A0903X01-Q0R0 Datasheet - Page 23

• Manufacturer Part Number: S1A0903X01-Q0R0
• Description: AM/FM 1 Chip Tuner with PLL
• Manufacturer: Samsung Electronics

AM/FM 1CHIP TUNER WITH PLL
1/N BLOCK
1/N block is used for frequency down-scaling from AM OSC. or FM OSC. to reference frequency Fr and
Prescaler, Swallow Counter, Main Counter is used for a natural number dividing.
Reference Divider : makes Fr divided by R[3:0] divisor from X'tal.
N = (16
= 17
Fc is derived from OSC. divided by N, N2 is derived from N[16:4] and N1 is derived from N[3:0]
Prescaler : operates on FM MODE.
Swallow Counter : counts down with N1 divisor and divides Fp by 17 on operation of swallow counter and
divide by 16 until S.C reloads N1 at the end of Fc 1 period.
Main Counter : makes Fc divided by N2 divisor from Fp divided by 16 or 17
A
B
N1 + 16
OS1
N2) + N1
1
0
FM OSC/2
AM OSC
(N2 - N1)
17XN1
XIN
OS0
N1
17
0
0
[A]
Figure 7. 1/N counting method
[B]
[C]
Figure 6. 1/N block diagram
1/16, 1/17
Input Frequency
Prescaler
N2
16X(N2-N1)
16
FM / 2
AMLF
Reference
Divider
fp
N[3:0]
N[15:0]
Swallow
Counter
Counter
12
Main
R[3:0]
fc
counting number of M.C
counting number of S.C
divisor of Prescaler
counting number of M.C
fr
AM = fr=fc=AMOSC/N
FM = fr=fc=FMOSC/2N
N Divider
Frequency
Detector
Input Frequency Range
Phase
0.5
5
E
80 MHz
10 MHz
S1A0903X01
23