Data Sheet
February 2001
L7583A/B/C/D Line Card Access Switch
The L7583 operates off of a 5 V supply only. This gives
the device extremely low idle and active power dissipa-
tion and allows use with virtually any range of battery
voltage. This makes the L7583 especially appropriate
for remote power applications such as DAML or FOC/
FITL or other Bellcore TA 909 applications where
power dissipation is particularly critical.
Description (continued)
The L7583Bxx and L7583Dxx versions provide only an
integrated diode bridge along with current limiting and
thermal shutdown (see Figure 2 for version B). This will
cause positive faults to be directed to ground and neg-
ative faults to battery. In either polarity, faults are
reduced by the current-limit and/or thermal shutdown
mechanisms.
A battery voltage is also used by the L7583, only as a
reference for the integrated protection circuit. The
L7583 will enter an all OFF state upon loss of battery.
To protect the L7583 from an overvoltage fault condi-
tion, use of a secondary protector is required. The sec-
ondary protector must limit the voltage seen at the tip/
ring terminals to prevent the breakdown voltage of the
switches from being exceeded. To minimize stress on
the solid-state contacts, use of a foldback- or crowbar-
type secondary protector is recommended. With proper
choice of secondary protection, a line card using the
L7583 will meet all relevant ITU-T, LSSGR, FCC, or
UL* protection requirements.
During power ringing, to turn on and maintain the ON
state, the ring access switch and ring test switch will
draw a nominal 2 mA or 4 mA from the ring generator.
The L7583A/B/C/D device is packaged in a 24-pin,
plastic DIP (L7583AF/BF/CF/DF) and in a 28-pin,
plastic SOG (L7583AAJ/BAJ/CAJ/DAJ).
* UL is a registered trademark of Underwriters Laboratories, Inc.
Pin Information
FGND
1
28 VBAT
FGND
NC
1
2
24 VBAT
SCR
AND
TRIP
CKT
NC
NC
2
3
4
27
26
NC
NC
23 NC
3
22 NC
NC
25 NC
SW1
SW2
NC
4
21 RTESTin
20 RBAT
19 RLINE
18 RRINGING
17 RTESTout
TTESTin
TBAT
SW1
SW2
TTESTin
5
6
7
24
23
RTESTin
RBAT
5
TBAT
SW3
SW4
SW3
SW4
6
TLINE
TRINGING
TTESTout
NC
TLINE
22
21
SW5
RLINE
SW6
SW5
7
8
TRINGING
NC
SW6
SW7
SW8
SW7
8
9
10
11
20
19
18
NC
TTESTout
NC
RRINGING
RTESTout
LATCH
SW9
SW10
SW8
LATCH
INTESTin
INRING
9
16
15
14
13
SW9
SW10
10
11
12
VDD
CONTROL
LOGIC
VDD 12
17
16
INTESTin
CONTROL
LOGIC
TSD
INRING
TSD
13
14
INTESTout
DGND
INTESTout
15
DGND
12-2364.a (F)
12-2365.d (F)
Note: Shown with A/C version protection. The 24-pin DIP is avail-
able with either A/C or B/D version protection.
Note: Shown with B/D version protection. The 28-pin SOG is avail-
able with either A/C or B/D version protection.
Figure 1. 24-Pin, Plastic DIP (600 mil)
Figure 2. 28-Pin, Plastic SOG
2
Lucent Technologies Inc.
AGERE [ AGERE SYSTEMS ]
