peb2025 ETC-unknow, peb2025 Datasheet - Page 7

• Manufacturer Part Number: peb2025
• Description: Isdn Exchange Power Controller
• Manufacturer: ETC-unknow

PEB 2025
Functional Description
Figure 2 shows the IEPC organization. The exchange power controller contains one line driver for
each of the four transmission lines. A line oriented register architecture allows very simple software
control.
Figure 3 shows the functional diagram of one of the four line drivers. The IEPC consists of a high
voltage analog part and a low voltage digital part.
The ground battery (positive supply voltage) has to be connected to GND (pin 11).
When powering up the IEPC, the line drivers are switched off and all registers are cleared. The
same initialized state can be achieved by an external high signal applied to the pin RES.
Analog Part
Power Switches
The negative pole of the supply, e.g. an exchange battery, has to be connected to the pin
V
.
BAT
After an ON-command to line i, a high voltage MOS-FET will connect the negative supply voltage
V
from
to aFi.
BAT
Current Control
The current of each negative wire (aFi) is controlled individually.
R
The maximum feeding current is programmed by an external resistor
connected between pin
I
R
and GND (see figure 1) and is same to all four lines.
Imax
C
aFi Line Control: Connecting an external capacitor
between CLCi and GND (see figure 1),
Ti
the IEPC offers a special time and current dependent turn off characteristic. The IEPC will limit the
aFi line current to protect the IEPC against over currents and to avoid discharging of the feeding
source. Figure 4 shows this transient permitted overload (TPO) state.
Semiconductor Group
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