T4260-IL Atmel, T4260-IL Datasheet - Page 20

• 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: -

DAC1, 2 (Pins 1, 2)
20
T4260
Table 25. Oscillator Operating Modes
For automatic tuner alignment, the DAC1 and DAC2 of the IC can be controlled by set-
ting gain and offset values. The principle of the operation is shown in Figure 7. The gain
is in the range of 0.67
For alignment, DAC1 and DAC2 are connected to the varicaps of the preselection filter
and the IF filter. For alignment, offset and gain are set for having the best tuner tracking.
Figure 7. Block Diagram of DAC1, 2
The gain of DAC1 and DAC2 has a range of approximately 0.67
2.09
(2.09 - 0.67)/255 = 0.00557
38 to 45 (2
(2
Table 26. Gain of DAC1, 2
Note:
0.6728
0.6783
0.6838
0.6894
0.9959
2.0821
2.0877
2.0932
0
Approximately
Approximately
to 2
Oscillator
Gain DAC1
Gain DAC2
OFF
ON
ON
7
V(TUNE). This range is divided into 255 steps. One step is approximately
) as given in Table 26.
Offset = 64 (intermediate position)
...
...
V(TUNE)
V(TUNE)
V(TUNE)
V(TUNE)
V(TUNE)
V(TUNE)
V(TUNE)
V(TUNE)
0
to 2
7
VTUNE
) and the gain of DAC2 can be controlled by the bits 66 to bit 73
Oscillator Buffer
B45
B73
...
...
0
0
0
0
0
1
1
1
OUTPUT
V
INPUT
OFF
TUNE
B44
B72
...
...
0
0
0
0
0
1
1
1
V(TUNE). The gain of DAC1 can be controlled by the bits
to 2.09
Gain
B43
B71
...
...
0
0
0
0
1
1
1
1
B42
B70
V
...
...
0
0
0
0
1
1
1
1
TUNE
AMLF (standard)
AMLF (standard)
INPUT f. DAC’s
AMLF (Pin 17)
. The offset range is +0.98 V to -0.98 V.
B41
B69
Offset
...
...
+/-
0
0
0
0
1
1
1
1
B40
B68
...
...
0
0
0
0
0
1
1
1
DAC1, 2
B39
B67
...
...
0
0
1
1
1
0
1
1
B38 Decimal Gain
B66 Decimal Gain
...
...
0
1
0
1
0
1
0
1
B65
0
1
1
4528J–AUDR–11/04
V(TUNE) to
253
254
255
58
...
...
0
1
2
3
B64
X
0
1