T4260-ILSH Atmel, T4260-ILSH Datasheet - Page 21

• Manufacturer Part Number: T4260-ILSH
• Description: IC AM/FM FRONT END W/PLL 44SSOP
• Manufacturer: Atmel

Specifications of T4260-ILSH

• 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: Lead free / RoHS Compliant
• Features: -
• Sensitivity: -
• Memory Size: -
• Data Rate - Maximum: -

10.17 Fractional Mode
10.18 Spurious Suppression
4528N–AUDR–11/09
The activated fractional mode (bit 144 = 0) in connection with the direct shift (bit 32 = 0) allows
fast frequency changes (with the help of the 2-bit shift) with a four times higher step frequency.
After the frequency change, the normal step frequency is active again.
If the fractional mode is deactivated (bit 144 = 1) and direct shift mode is active, (bit 32 = 0) the
VCO frequency is set to the next lower frequency which is many times the amount frequency of
4 times step frequency. This means that the 2 shifted bits of the active N-Divider are not used in
this mode. The shift bits are interpreted as logic 0.
The fractional mode with direct shift mode deactivated (bit 32 = 1) allows normal frequency
changes with a step frequency of 12.5 kHz.
Table 10-19. Fractional Mode
In fractional and direct shift mode the spurious suppression is able by SW wire and SW impulse.
Table 10-20. Spurious Suppression by SW Wire
Table 10-21. Spurious Suppression by Correction Current Charge Pump
SW Impulse
Fractional
SW Wire
OFF
OFF
OFF
ON
ON
ON
B144
B61
B60
0
1
0
1
0
1
T4260
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