Data Sheet
March 1997
L7554 Low-Power SLIC
Electrical Characteristics (continued)
Table 9. Logic Inputs and Outputs
All outputs except RGDET are open-collector with internal pull-up resistor. RGDET is open-collector without inter-
nal pull-up.
Parameter
Input Voltages
Low Level (permissible range)
High Level (permissible range)
Input Currents
Low Level (VCC = 5.25 V, VI = 0.4 V)
High Level (VCC = 5.25 V, VI = 2.4 V)
Output Voltages (open-collector with internal pull-up
resistor)
Low Level (VCC = 4.75 V, IOL = 360 µA)
High Level (VCC = 4.75 V, IOH = –20 µA)
Symbol
VIL
VIH
IIL
IIH
Min
Typ
Max
Unit
–0.5
0.4
0.7
V
2.0
2.4
VCC
V
—
–115 –200
µA
—
–60
–100
µA
VOL
0
0.2
0.4
V
VOH
2.4
—
VCC
V
Ring Trip Requirements
s Ringing signal:
— Voltage, minimum 35 Vrms, maximum 100 Vrms.
— Frequency, 17 Hz to 23 Hz.
— Crest factor, 1.4 to 2.
s Ringing trip:
— ≤100 ms (typical), ≤250 ms (VBAT = –33 V, loop
length = 530 Ω).
s Pretrip:
— The circuits in Figure 3 will not cause ringing trip.
200 Ω
TIP
SWITCH CLOSES < 12 ms
6 µF
TIP
10 kΩ
2 µF
100 Ω
TIP
Figure 3. Ring Trip Circuits
RING
RING
RING
12-2572 (C)
Lucent Technologies Inc.
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