am79r251 Advanced Micro Devices, am79r251 Datasheet - Page 20

• Manufacturer Part Number: am79r251
• Description: Intelligent Subscriber Line Interface Circuit Islic
• Manufacturer: Advanced Micro Devices

Am79R251 Ringing Specifications
Am79R251 Current-Limit Behavior
Am79R251 Fault Indications
20
Notes:
1. Unless otherwise specified, test conditions are: VCC = 5 V, RMG1 = RMG2 = 1 k , BATH = -68 V,
2. These tests are performed with the following load impedances:
3. Not tested or partially tested in production. This parameter is guaranteed by characterization or correlation
4. This parameter is tested at 1 kHz in production. Performance at other frequencies is guaranteed by
5. When the Am79R251 and ISLAC device is in the anti-sat operating region, this parameter is degraded. The
6. –55 dBm gain tracking level not tested in production. This parameter is guaranteed by characterization and
7. This spec is valid from 0 V to VBL or –50 V, whichever is lower in magnitude.
8. Other ringing-voltage characteristics are set by the ISLAC device.
Peak Ringing Voltage
Disconnect
Tip Open
Standby
No Fault
Thermal Shutdown
Active Ringing
SLIC Mode
BATL = -40 V, BATP = +52 V, RRX = 150 k , RL = 600 , RSA = RSB = 200 k , RFA = RFB = 50
ISLAC device. When the Am79R251 is tested by itself, its operating conditions must be simulated
as if it were connected to an ideal ISLAC device.
Frequency < 12 kHz – Longitudinal impedance = 500 ; metallic impedance = 300
Frequency > 12 kHz – Longitudinal impedance = 90 ; metallic impedance = 135
to other tests.
characterization.
exact degradation depends on system design.
correlation to other tests.
, CHP = 22 nF, CAD = CBD = 22 nF, IRSN = 50 A. DC-feed conditions are normally set by the
Item
Fault
Applied fault between ground and T/R
VBH applied to Tip or Ring
Short to GND
Short Tip-to-VBH
Short Ring-to-GND
ISLAC generating internal ringing
RT Network
Active Internal Ringing
Condition
IMT operates normally (Vref ±1V)
IMT above 2.8 V; ILG operates normally
Condition
Am79R251
30 K
VREF
Indication
VBH+5
30 K
Min
390 pf
Min
Typ
VBH/200K
Typ
100
30
30
30
1
VBP–5
Max
Max
100
Unit
Unit
V
Unit
mA
A
A
Note
Note
Note
8
7