AD6650ABCZ Analog Devices Inc, AD6650ABCZ Datasheet - Page 35

• Manufacturer Part Number: AD6650ABCZ
• Description: DIVERSITY IF-TO-BASEBAND GSM/EDGE NARROW-BAND RECEIVER
• Manufacturer: Analog Devices Inc

Reg.
(Hex)
D
E
F
Mnemonic
AGC Control 1
8 to 0: VGA Gain
AGC Control 2
AGC Control 3
15 to 8: Hysteresis
7 to 0: Requested Level
10 to 8: Loop Gain
Exponent
7 to 6: Reserved
5 to 0: Loop Gain
Mantissa
Bit
Width
9
16
8
8
11
3
2
6
Description
VGA gain (dB) = (0.094) × VGA gain word.
This drives the VGA directly when force VGA
gain = 1.
AGC hysteresis and requested level.
Upper hysteresis threshold = requested level
+ hysteresis.
Lower hysteresis threshold = requested level
− hysteresis.
The gain word does not change if the peak
measurement falls between the upper and
lower hysteresis threshold.
The requested level for the slow loop. The
full-scale input into the AD6650 is
2 V p-p = 4 dBm.
Loop gain = (mantissa/256) × ½
Loop gain exponent (slow loop).
Reserved.
Loop gain mantissa (slow loop).
Rev. A | Page 35 of 44
exponent
.
Additional Information
Code
0
1
2
.
.
382
383
Code
0
1
2
.
.
254
255
Code
0
1
2
.
.
254
255
Code
0
1
.
.
6
7
N/A
Code
0
1
2
.
.
62
63
Gain (dB)
0 dB
0.094 dB
0.188 dB
.
.
35.9 dB
36.002 dB
Hysteresis (dB)
0
±.094 dB
±.188 dB
.
.
±23.876 dB
±23.97 dB
Requested
Level (dBm)
+4 dBm
+3.906 dBm
+3.812 dBm
.
.
−19.8 dBm
−19.97 dBm
Loop Gain Exp
2
2
.
.
2
2
Mantissa
0
1
2
.
.
62
63
0
1
6
7
AD6650