L7583A Datasheet, PDF (16/20 Pages) Agere Systems – Line Card Access Switch

L7583A/B/C/D Line Card Access Switch
Data Sheet
February 2001
Application (continued)
Table 16. Truth Table for L7583A/B
INRING
0V
0V
0V
5V
5V
0V
5V
5V
Don’t
Care
INTESTin INTESTout
0V
0V
5V
0V
5V
5V
0V
5V
Don’t
Care
0V
5V
0V
0V
0V
5V
5V
5V
Don’t
Care
TSD
5 V/Float¹
5 V/Float¹
5 V/Float¹
5 V/Float¹
5 V/Float¹
5 V/Float¹
5 V/Float¹
5 V/Float¹
0 V²
TESTin
Switches
Off
Off
On
Off
Off
On
Off
Off
Off
Break
Switches
On
Off
Off
Off
Off
Off
Off
Off
Off
Ring Test
Switches
Off
Off
Off
Off
On
Off
Off
Off
Off
Ring TESTout
Switches Switches
Off
Off³
Off
On⁴
Off
Off⁵
On
Off⁶
Off
Off⁷
Off
On⁸
Off
Off⁹
Off
Off⁹
Off
Off⁹
1. If TSD = 5 V, the thermal shutdown mechanism is disabled. If TSD is floating, the thermal shutdown mechanism is active.
2. Forcing TSD to ground overrides the logic input pins and forces an all OFF state.
3. Idle/Talk state.
4. TESTout state.
5. TESTin state
6. Power ringing state.
7. Ringing generator test state.
8. Simultaneous TESTout and TESTin state.
9. All OFF state.
A parallel in/parallel out data latch is integrated into the L7583A/B. Operation of the data latch is controlled by the
logic level input pin LATCH. The data input to the latch is the INPUT pin of the L7583A/B, and the output of the data
latch is an internal node used for state control.
When the LATCH control pin is at logic 0, the data latch is transparent and data control signals flow directly from
INPUT, through the data latch to state control. Any changes in INPUT will be reflected in the state of the switches.
When the LATCH control pin is at logic 1, the data latch is active—the L7583A/B will no longer react to changes at
the INPUT control pin. The state of the switches is now latched; that is, the state of the switches will remain as they
were when the LATCH input transitioned from logic 0 to logic 1. The switches will not respond to changes in INPUT
as long as LATCH is held high.
Note that the TSD input is not tied to the data latch. TSD is not affected by the LATCH input. TSD input will override
state control via INPUT and LATCH.
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Lucent Technologies Inc.