L9214A/G
Low-Cost Ringing SLIC
Preliminary Data Sheet
October 2001
Operating States
Table 2. Control States
B3
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
B2
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
B1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
B0
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
State
Disconnect
Ringing, (line reverse with high slope)
Unused*
Ringing, (line forward with high slope)
Disconnect
Reverse active and on-hook, fast polarity reversal
Scan
Forward active and on-hook, fast polarity reversal
Disconnect
Ringing, (line reverse with low slope)
Unused*
Ringing, (line forward with low slope)
Disconnect
Reverse active and on-hook, slow polarity reversal
Scan
Forward active and on-hook, slow polarity reversal
* In this state, all supervision functions are disabled, on hook transmission is disabled, pin PT is positive with respect to PR, VBAT1 is applied to
tip/ring, and the tip to ring voltage will be equivalent to the scan state.
■ Loop closure and common-mode detect are active.
State Definitions
■ Ring trip detector is turned off to conserve power.
Forward Active (Fast Polarity Reversal)
■ On-hook transmission is enabled.
Off-hook
■ Overhead is set to nominal 17.0 V for undistorted
transmission of 0 dBm into 600 Ω.
■ Pin PT is positive with respect to PR.
■ VBAT2 is applied to tip/ring drive amplifiers for the
majority of loop lengths. This may also be derived
from VBAT1 through a power control resistor.
Forward Active (Slow Polarity Reversal)
Off-hook
■ Loop closure and common-mode detect are active.
■ Ring trip detector is turned off to conserve power.
■ Same as the forward active (fast polarity reversal)
state, but with slower polarity reversal.
■ Overhead is set for undistorted transmission of
+3.17 dBm into 600 Ω.
On-hook
On-hook
■ Same as the forward active (fast polarity reversal)
state, but with slower polarity reversal.
■ Pin PT is positive with respect to PR.
■ VBAT1 is applied to tip/ring drive amplifiers. The tip to
ring on-hook differential voltage will be between
–42.5 V and –56.5 V with a primary battery of –65 V.
12
Agere Systems Inc.
AGERE [ AGERE SYSTEMS ]
