T4260-ILQH Atmel, T4260-ILQH Datasheet - Page 23

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

Specifications of T4260-ILQH

• 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: -

10.21 DAC1, 2 (Pins 1, 2)
4528N–AUDR–11/09
For automatic tuner alignment, the DAC1 and DAC2 of the IC can be controlled by setting gain
and offset values. The principle of the operation is shown in
of 0.67
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 10-3. Block Diagram of DAC1, 2
The gain of DAC1 and DAC2 has a range of approximately 0.67
This range is divided into 255 steps. One step is approximately (2.09 – 0.67)/255 =
0.00557
gain of DAC2 can be controlled by the bits 66 to bit 73 (2
Table 10-25. Gain of DAC1, 2
Note:
0.6728
0.6783
0.6838
0.6894
0.9959
2.0821
2.0877
2.0932
Approximately
Approximately
Gain DAC1
Gain DAC2
Offset = 64 (intermediate position)
...
...
V
V(TUNE)
V(TUNE)
V(TUNE)
V(TUNE)
V(TUNE)
V(TUNE)
V(TUNE)
V(TUNE)
V(TUNE). The gain of DAC1 can be controlled by the bits 38 to 45 (2
TUNE
to 2.09
VTUNE
B45
B73
...
...
0
0
0
0
0
1
1
1
V
TUNE
B44
B72
...
...
0
0
0
0
0
1
1
1
. The offset range is +0.98V to –0.98V. For alignment, DAC1
Gain
B43
B71
...
...
0
0
0
0
1
1
1
1
B42
B70
...
...
0
0
0
0
1
1
1
1
Offset
B41
B69
+/-
...
...
0
0
0
0
1
1
1
1
0
to 2
Figure
B40
B68
...
...
0
0
0
0
0
1
1
1
7
) as given in
DAC1, 2
V(TUNE) to 2.09
10-3. The gain is in the range
B39
B67
...
...
0
0
1
1
1
0
1
1
B38
B66
Table
...
...
0
1
0
1
0
1
0
1
0
10-25.
Decimal Gain
Decimal Gain
to 2
T4260
7
V(TUNE).
) and the
253
254
255
58
...
...
0
1
2
3
23