AM79212JC AMD (ADVANCED MICRO DEVICES), AM79212JC Datasheet - Page 8

• Manufacturer Part Number: AM79212JC
• Manufacturer: AMD (ADVANCED MICRO DEVICES)

Specifications of AM79212JC

• Lead Free Status / RoHS Status: Supplier Unconfirmed

PIN DESCRIPTIONS
ASLIC Device
AD, BD
A and B Line Drivers (Output)
These pins provide the currents to the A and B leads of
the subscriber loop.
BAL1, BAL2
Pre-balance (Input)
These pins receive voltages that are added to the VTX
output signal. They can be used to cancel out the
metering echo in the transmit path.
BGND
Battery Ground
This pin connects to the ground return for Central Office
or talk battery.
C2–C1
ASLIC Device Control (Input)
These ternary logic input pins control the operating state
of the ASLIC device.
C5–C3
Test Relay Control (Input)
These are control inputs for the test relay drivers in the
ASLIC device. A logic Low turns on the relay driver and
activates the relay. C3 controls RY1OUT, C4 controls
RY2OUT, and C5 controls RY3OUT.
GND
Ground
Analog and digital ground return for VCC.
HPA, HPB
High-Pass Filter Capacitor Connections
These pins connect to CHP, the external high-pass filter
capacitor that isolates the DC control loop from the voice
transmission path.
IDC
DC Loop Control Current (Input)
The DC loop current control line from the ASLAC device
is connected to this pin. An internal resistance is
provided between the IDC pin and RSN. An external
noise filter capacitor should be connected between this
pin and VREF.
IDIF
A – B Leg Current (Output)
The current at this pin is proportional to the difference
of the currents flowing out of the AD pin and into the BD
pin of the ASLIC device.
8
Am79212/Am79C202 Data Sheet
P R E L I M I N A R Y
ISUM
A + B Leg Current (Output)
The current at this pin is proportional to the absolute
value of the sum of the currents flowing out of the AD
pin and into the BD pin of the ASLIC device.
RINGOUT, RY1OUT, RY2OUT, RY3OUT
Relay Drivers (Output)
These are open collector, high-current relay driver
outputs with emitters internally connected to BGND. To
absorb the inductive pulse from the relay coils, an
internal Zener diode is connected between the collector
of each driver and BGND.
RSN
Receive Summing Node (Input)
The metallic current (both AC and DC) between AD and
BD is equal to the ASLIC device current gain, K1, times
the current into this pin. Networks that program receive
gain and two-wire impedance connect to this node. This
input is nominally at VREF potential.
RSVD
Reserved (Input)
This is used during AMD testing. In the application, this
pin must be floating.
SA, SB
A and B Lead Voltage Sense (Input)
These pins sense the voltages on the line side of the
fuse resistors at the A and B leads. External sense
resistors, RSA and RSB, are required to protect these
pins from lightning or power cross conditions.
TMG
Thermal Management
A resistor connected from this pin to VBAT reduces the
on-chip power dissipation by absorbing excess power
from the ASLIC device for short loop conditions.
VBAT
Battery Voltage (Power)
This pin supplies battery voltage to the line drivers.
VCC
Power Supply (Power)
This pin is the positive supply for low-voltage analog and
digital circuits in the ASLIC device.