AT&T AT&T manual Unique Tip Ring Line ZTN78 Circuitry

Tip Ring Line (ZTN78)

The Tip Ring Line Circuit Pack interfaces eight analog tip and ring voice terminal lines (single-line voice terminals) and the TDM bus. Figure 3-10 shows the following Tip and Ring

Line unique circuitry:

● Ringing application circuit

● Port Input/Output (I/O) circuit

● Eight port circuits.

NPE O

NPE 1

P O R T

I/O

CIRCUIT

ON-BOARD

MICRO-

PROCESSOR

RINGING

APPLICATION

CIRCUIT

POWER

●

SUPPLY

–48V TO –24V

POWER

CONDITIONER

						PORT
						CIRCUIT
							0
					CODEC			ELECTRONIC
						HYBRID			BATTERY
									FEED
				●
						❘				T.O \
						❘
						❘				R.O
			●			❘				T.3
						PORT
			●
		●				CIRCUIT				R.3
							3
	●
										T.4
			●			PORT
		●
	●					CIRCUIT				R.4
							4
●
							❘
							❘
							❘			T.7
						PORT
						CIRCUIT				R.7
	●
							7
											/

TO ANALOG TIP/RING TERMINALS

Figure 3-10. Unique Tip Ring Line (ZTN78) Circuitry

3-20