ad6472 Analog Devices, Inc., ad6472 Datasheet - Page 6

• Manufacturer Part Number: ad6472
• Description: 2 Pair/1 Pair Etsi Compatible Hdsl Analog Front End
• Manufacturer: Analog Devices, Inc.

AD6472
Receive Channel
Hybrid Amplifier
The hybrid amplifier performs balanced to unbalanced
conversion.
Programmable Gain Amplifier (PGA)
The PGA can be programmed to amplify the receive signal
from between –6 dB and 9 dB. Refer to Table II for PGA gain
control information.
Receive Channel
MODE_SEL1
0
0
1
1
Pin
5
6
7
8
9
11
13
HYB_IN1_A
HYB_IN1_B
HYB_IN2_A
HYB_IN2_B
PGA_GC2
0
0
0
0
1
1
1
1
Mnemonic
AA_FLTR_BP
PWRDN
ADC_BUF_BP
TX_GAIN_SEL
TX_DRVR_BP
TX_LPF_BP
LOOPBACK
10k
10k
10k
10k
Figure 3.
10k
10k
Filter Control Bit
MODE_SEL0
0
1
0
1
Gain Control Bit
TO PGA
PGA_GC1
0
0
1
1
0
0
1
1
Table IV. Configuration Control
Logic 0 = Function
Receive Filter in Circuit
Low Power Selected
ADC Buffer in Circuit
0 dB Attenuation
Line Driver in Circuit
Transmit Filter in Circuit
Normal Operation
Table III.
Table II.
–6–
Transmit and Receive Filters
Refer to Table III for transmit and receive channels filter
control information. The receive channel filters meet ETSI
requirements.
Analog-to-Digital Converter (ADC)
The receive channel ADC has a pipeline architecture with 12-
bit resolution. The ADC can be clocked at 2320 kHz, maxi-
mum. Output data is provided in 2s complement form.
Timing Recovery D/A
The AD6472 has an integrated D/A converter to control an
external VCXO used for timing recovery. The D/A is 7 bits and
monotonic. The D/A accepts 7 bits inverted format input data
serially with the MSB first.
Configuration Control
Table IV presents control information that you use to configure
the AD6472.
PGA_GC0
0
1
0
1
0
1
0
1
Receive Clock
Frequency (kHz)
1168/2
Reserved
1160
1160
2
–6
–3
Binary Count
GAIN (dB)
0
3
6
9
9
9
Logic 1 = Function
Receive Filter Bypassed
Normal Operating Mode
ADC Buffer Bypassed
6 dB Attenuation
Line Driver Bypassed
Transmit Circuit Bypassed
Analog Loopback Selected
3 dB Frequency
(kHz)
Rx = 320/Tx = 320
Reserved
Rx = 640/Tx = 535
Rx = 640/Tx = 535
REV. 0