T4260-IL Atmel, T4260-IL Datasheet - Page 23

• Manufacturer Part Number: T4260-IL
• Description: IC RECEIVER AM/FM FRONT 44-SSOP
• Manufacturer: Atmel

Specifications of T4260-IL

• Frequency: AM, FM
• Modulation Or Protocol: AM, FM
• Applications: AM/FM Radio Receiver
• Current - Receiving: 85mA
• Data Interface: PCB, Surface Mount
• Antenna Connector: PCB, Surface Mount
• Voltage - Supply: 8 V ~ 10 V
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-SSOP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Features: -
• Sensitivity: -
• Memory Size: -
• Data Rate - Maximum: -

Figure 11. Block Diagram of the PLL Core
PLL Core Block Diagram
Description
4528J–AUDR–11/04
LATCH N - DIV 1
f
ref
18 - BIT
LATCH R - DIV.
MUX N1 N2
SHIFT 2 BIT
R - DIVIDER
SHIFT 2 BIT
DIVIDER
14 - BIT
N/N+1
B5
18 - BIT
LATCH N - DIV 2
The two N-dividers are stored in two 18-bit memory register (LATCH N-DIV) and the
R-divider in a 14-bit memory register (LATCH R-DIV). One of the two N-dividers
(N1 or N2) can be activated by bit 5 as active N-divider (with the 18-bit multiplexer
MUX).
The (divider) 2-bit shift mode can be activated with bit 32 = 0. The N- and R-divider are
shifted two bits to the right in this shift mode. Because the two lowest R-divider bits
(bit 124 and bit 125) are 0 they do not have to be evaluated. In opposite to the R-divider
the lowest two N-divider bits (bit 102 and bit 103 or bit 80 and bit 81, depends on the
active N-divider) are special evaluated in the ACCU block if fractional mode is active
(bit 144 = 0). The two lowest N- and R-divider bits are also called shift bits.
The SWITCH N+1, N block is steering the division through N or N+1 in the N-divider if
fractional and 2-bit shift mode are active. There is only a division by N if the fractional
mode is deactivated in 2-bit shift mode.
The output signals of the 18-bit N-divider and 14-bit R-divider will be compared in the
PHASEDETECTOR which one activates the sink and source currents of the charge
pumps (CP).
2 - BIT (LSB)
DETECTOR
PHASE
SWITCH N+1, N
ACCU 2 - BIT
B60, B144
SWITCH
PREAMP
DELAYTIME
high cur. CP
HCDEL 1 HCDEL 2
CHARGE
PUMP
BIT 18
BIT 32
B61
FILTER
AM/FM
AM/FM
B62,63
B145
AM - LOOP
FM - LOOP
FILTER
FILTER
VCO
T4260
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