Le79R241 Data Sheet
17
Zarlink Semiconductor Inc.
6.2 DC Specifications
Unless otherwise specified, test conditions are: VCC = 5 V, RMGP
i
= RMGL
i
= 1 k, BATH =
–90 V, BATL = –36 V, RRX = 150 k, RL = 600 , RSA = RSB = 200 k, RFA = RFB = 50 ,
CHP = 22 nF, CAD = CBD = 22 nF, IRSN = 50 A, Active low battery. DC-feed conditions are
normally set by the 790 series codec. When the Le79R241 ISLIC device is tested by itself, its
operating conditions must be simulated as if it were connected to an ideal 790 series codec.
No. Item Condition Min. Typ. Max. Unit Note
1
Two-wire loop voltage
(including offset)
Standby mode, open circuit,
|VBH| < 55 V
|VBH| > 55 V
GND VB
Any Active mode (does not
include OHT),
RL = 600 , I
RSN
= 50 µA
OHT mode, RL = 2200
I
RSN
= 20 µA
VBH – 8
48
13.88
19.8
VBH–7
51
15
22
VBH–6
55.5
55.5
16.13 V 2.
2
Feed resistance per leg
at pins AD & BD
Standby mode 130 250 375
ohm
s
2.
3
Feed current limit
Feed current
Standby mode, RL = 600
18 34 45 mA
IMT current
Standby mode, RL = 2200
44.6 56
µA
ILG current
Standby mode
A to VBH
B to Ground
28
28
4
Ternary input voltage
boundaries for LD pin.
Mid-level input source
must be Vref.
Low boundary
Mid boundary
High boundary
Input high current
Input low current
Mid-level current
VREF–0.
3
CREF – 1
V
REF
108
47
51
0.6
VREF+0.
3
V
V
V
µA
µA
µA
2.
2.
2.
5 Logic Inputs P1, P2, P3
Input high voltage
Input low voltage
Input high current
Input low current
2.0
-20
-20
0
0
0.8
20
20
V
V
µA
µA
6 VTX output offset –50 0 +50 mV
7 VREF input current VREF = 1.4 V 50 µA 2.
8 CREF input current CREF = 3.3 V -3 0 3 µA 2.
9
ß, DC Ratio of VSAB to
loop voltage:
Tj < 145°C, VSA – VSB = 22 V 0.0088 0.0097 0.0106 V/V
10
Fault Indicator
Threshold
Voltage Output on IMT 2.8 CREF – 0.3 V CREF V 2.
11
Gain from VLB pin to A
or B pin, KLG
30 V/V
12 VLB pin input current VLB = VREF ± 1 V 0 100 µA 2.
13 ILOOP/IMT ILOOP = 10 mA 283 308 333 A/A
14 ILONG/ILG ILONG = 10 mA 575 615 655 A/A
390 pf
RT Network
30 k
Ω
30 k
Ω
VREF
V
SAB
V
SA
V
SB
–
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=
