Data Sheet
January 2000
L7556, L7557 Low-Power SLICs
with Battery Switch
Recommended Operating Conditions
Parameter
Min
Ambient Temperature
–40
VCC Supply Voltage
4.75
VBAT1 Supply Voltage
–24
VBAT2 Supply Voltage
–16
Loop Closure Threshold-detection Programming Range
—
dc Loop Current-limit Programming Range
5
On- and Off-hook 2-wire Signal Level
—
ac Termination Impedance Programming Range
150
Typ
Max
Unit
—
85
°C
5.0
5.25
V
–48
–60
V
–28
VBAT1
V
10
ILIM
mA
22
45
mA
1
2.2
Vrms
600
1300
Ω
Electrical Characteristics
Minimum and maximum values are testing requirements. Typical values are characteristic of the device and are
the result of engineering evaluations. Typical values are for information purposes only and are not part of the test-
ing requirements. Minimum and maximum values apply across the entire temperature range (–40 °C to +85 °C)
and the entire battery range unless otherwise specified. Typical is defined as 25 °C, VCC = 5.0 V, VBAT1 = –48 V,
VBAT2 = –48 V, and ILIM= 40 mA. Positive currents flow into the device. Test circuit is Figure 4 unless noted.
Table 4. Power Supply
Parameter
Min
Power Supply—Powerup, No Loop Current:
ICC
—
IBAT (VBAT = –48 V)
—
Power Dissipation (VBAT = –48 V)
—
Power Supply Rejection 500 Hz to 3 kHz (See Figures 5, 6, 15, and 16.)1:
VCC
35
VBAT
45
Thermal Protection Shutdown (Tjc)
—
Thermal Resistance, Junction to Ambient (θJA)
—
1. This parameter is not tested in production. It is guaranteed by design and device characterization.
Typ
2.8
–2.3
125
—
—
175
60
Max
Unit
—
mA
—
mA
155
mW
—
dB
—
dB
—
°C
—
°C/W
Lucent Technologies Inc.
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