Current detectors are designed to automatically detect loop current in the network control unit
of fax, modem and other office equipment. Comparing to photo coupler and relay used in the
same application, current detector offers following advantages:
Features
Low threshold current
Low input impedance
High isolation voltage
Current direction detection capability
High sensitivity of current detection function
Ultra-compact size
Superior reliability
Nemko/CB Report/VDE approvals
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Applications
The most common applications of current detectors include:
Fax Machine
Cordless Phone
Fax Card
Modem
Answering Machine
PBX
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Application Example
Cyntec's current detectors, designed to work with current over 10mA, are most suitable for
detecting loop current generated in the Network Control Unit (NCU). They offer a lot of
advantages to replace photocoupler and relay. A typical application is shown as below:
A current detector provides two basic functions
1. Manual operation:
When manually operating the telephone in a fax machine, the internal telephone function will
be disabled according to the output signal of the current detector.
2. Automatic operation:
Under automatic operation, a relay is used to replace the actual telephone hook. By
detecting the loop current condition, current detector sends a signal to provide the status of
the telephone line.
CURRENT
DETECTOR
RELAY
TELEPHONE
MODEM
TELEPHONE
RINGER
T
R
OP1 OP2 CHK* FAX
L1 L2
Current Detector
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Threshold Current
* 2mA for MA91000063
** 5mA for MA91000063
Specifications
*Vs= 0 dBm, Fc=1 KHz, Zs=600. Zl=600 Vi=-6 dBm
Item MA91000009 MA91000018 MA91000036 MA91000045 MA91000063
Supply Voltage (Vcc) +5V 5% +5V 5% +5V 5% +5V 5% +5V 5%
Isolation Voltage 4KV AC 4KV AC 2.2KV AC 3.75KV AC 2.2KV AC
Primary/Secondary for 1min. for 1min. for 1min. for 1min. for 1min.
o
Operating Temp. Range +0 C ~+50 +0 +50 -10 +70 +0 +50 +0 +50
Storage Temp. Range -20 ~+80 -20 +80 -20 +80 -20 +80 -20 +80
Input Resistance 3W max. 5W max. 5W max. 5W max. 5W max.
Input Inductance 0.5 mH Max. 0.7 mH Max. 0.7 mH Max. 0.7 mH Max. 1.2 mH Typ.
I/O Loss (Vo/Vi) * - - 33dB 3dB 0~3dB -
o oo oo oo oo
C C ~ C C ~ C C ~ C C ~ C
oo oo oo oo oo
C C C ~ C C ~ C C ~ C C ~ C
Item Condition Pin/Symbol Min. Typ. Max.
OP1 3.5V
OP2 3.5V
OP1 0.8V
OP2 3.5V
OP1 3.5V
OP2 0.8V
O
Input Current Ta=25 2 C Ii 120mA
Supply Current Ta=25 2 C Ic 10mA
O
L1 L2 5mA*
L1 L2 10mA**
L2 L1 10mA**
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Outline Dimension (Unit: mm)
Item MA91000009 MA91000018 MA91000036 MA91000045 MA91000063
Wide (W) 34.5 27 27 27 27
Thickness (T) 10 10 10 10 10
Height (H) 18 18 16 18 16
Pitch (P) 4 3 4 4 4
Distance 1 (D1) 15.24 10.16 5.08 7.62 5.08
Distance 2 (D2) 2 2 5 2 5
Item MA91000009 MA91000018 MA91000036 MA91000045 MA91000063
1 L1 L1 L1 L1 L1
2 L2 L2 L2 L2 L2
3 GND GND GND GND GND
4 CHK OP2 CHK CHK CHK
5 OP2 OP1 OP2 OP2 OP2
6 OP1 Vcc OP1 OP1 OP1
7 Vcc Vcc Vcc Vcc
Pin Assignment
MA910000XX
CYNTEC XXXX
12 34567
5.0 1
T Max.
0.25 Typ
H Max.
D1
2.54 X P
D2 Max.
W Max.
(Unit: mm)
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