L3000N datasheet(11/32 Pages) STMICROELECTRONICS

Part #	L3000N

Description	SLIC KIT OPTIMIZED FOR APPLICATIONS WITH BOTH FIRST AND SECOND GENERATION COMBOS

PDF	32 Pages

Scroll/Zoom	100%

Manufacturer	STMICROELECTRONICS [STMicroelectronics]

Direct Link	http://www.st.com

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11 / 32 page

If, for example, the loop resistance is 400

Ω the

GDK output will be 0 only when the limiting current

value is 40 or 25mA.

The card controller can program consecutive Test

Mode and Conversation Mode with different limiting

current in order to individuate the range of loop re-

sistance as shown in the flow chart of fig. 6.

The information of the Loop Resistance Range

can be very useful to optimize the transmission

characteristics of the Line Card to each line.

For example, if a second generation COMBO like

TS5070 is used the Card Controller can use this

information to change the Tx, RX Gains and echo

cancellation characteristics into the programma-

ble COMBO improving the quality of the system.

Limiting Current

GDK = 0

GDK = 1

60mA

40mA

25mA

(0 – 300) ohm

(0 – 650) ohm

(0 – 1300) ohm

>300 ohm

>650 ohm

>1300 ohm

Figure 6: Procedure for Loop Resistance Evaluation.

L3000N - L3092

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L3000N Datasheet(PDF) 11 Page - STMicroelectronics