peb2025 ETC-unknow, peb2025 Datasheet - Page 15

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

State Diagram
Figure 6 shows the state diagram of one IEPC line driver.
A logic high on the RES input sets the device into the initial state. The line driver is switched off and
all registers are cleared. The same initialized state is achieved by powering up the IEPC. After an
ON-command (ON = 1) the line drivers will turn on and the IEPC is in the FEEDING-state. To return
to the OFF-state the ON-bit must be cleared (ON = 0).
In the FEEDING-state the current
cases happens:
1. If an external capacitor
2. If
The temperature of each line driver is controlled separately. If the temperature of the line driver
exceeds the shut-off temperature, the transmission line will turn off and the line driver is in the
STOP-state. In this case the shut-off temperature of the other three line drivers will be increased.
There are two different ways to leave the STOP-state:
1. If the automatic restart bit is set (AR = 1) the IEPC returns after a delay time to the FEEDING-
2. If no automatic restart mode is selected (AR = 0) the IEPC returns to the OFF-state. In this case
As soon as the STOP-state is reached the IEPC sends an interrupt signal to the microprocessor
(interrupt-pin is active low).
If the line driver is not in the terminal overload state, every rising edge of the read signal resets the
interrupt bit INTi (D0i) of the selected line i. The current overload-bit C0i (D2i) will be reseted too.
If the line driver i is in the terminal overload state the rising edge of the read signal has no effect on
the interrupt bit.
The internal interrupts INT0 - INT3 are anded to the open drain output pin INT. So the interrupt pin
stays activ low until all interrupt bits INT
Semiconductor Group
IEPC stays in the Transient Permitted Overload-state (TPO). Exceeding the time-current-limit
the line driver turns off and the IEPC is in the STOP-state. The current overload-bit will be set
(CO = 1) and
completely, an ON command will be ignored. If no exceeding happens the line driver returns to
the FEEDING-state.
current overload bit will not be set.
state automatically. The ON/OFF register will not be cleared.
the ON/OFF register will be cleared.
I
aFi
I
max
is detected and CLCi is connected to GND the IEPC limits the driver current. The
C
Ti
will be discharged by an resistor of the IEPC. Until
C
Ti
is connected between CLCi and GND and
I
aFi
is controlled. If overcurrent is detected one of the following
i
are reseted.
15
I
aFi
C
I
Ti
max
isn´t discharged
is detected the
PEB 2025