L7583A/B/C/D Line Card Access Switch
Data Sheet
February 2001
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.
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.
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.
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.
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.
Pin Information
F
GND
NC
NC
T
TESTin
T
BAT
T
LINE
T
RINGING
T
TESTout
NC
1
2
3
SW1
SW2
SCR
AND
TRIP
CKT
24 V
BAT
23 NC
22 NC
21 R
TESTin
F
GND
NC
NC
NC
T
TESTin
1
2
3
4
SW1
SW2
28 V
BAT
27 NC
26 NC
25 NC
24 R
TESTin
23 R
BAT
SW3
SW5
SW6
SW7
SW4
4
5
6
7
SW7
SW8
SW10
SW3
SW5
SW4
SW6
5
6
7
8
9
SW8
SW9
SW10
20 R
BAT
19 R
LINE
18 R
RINGING
17 R
TESTout
16 LATCH
15 IN
TESTin
CONTROL
LOGIC
T
BAT
T
LINE
T
RINGING
NC
22 R
LINE
21 NC
20 R
RINGING
19 R
TESTout
18 LATCH
8
9
SW9
T
TESTout
10
NC 11
V
DD
12
T
SD
13
V
DD
10
T
SD
11
D
GND
12
14 IN
RING
13 IN
TESTout
CONTROL
LOGIC
17 IN
TESTin
16 IN
RING
15 IN
TESTout
12-2365.d (F)
D
GND
14
12-2364.a (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 ]
