Operating Information
Fuse Considerations
To prevent excessive current from flowing through the input sup-
ply line, in the case of a short-circuit across the converter input, an
external fuse should be installed in the non-earthed input supply
line. We recommend using a fuse rated at approximately 2 to 4
times the value calculated in the formula below:
POmax
Iin
=
max
(hmin × V min
)
I
Refer to the fuse manufacturer for further information.
Remote Control (RC)
Turn-on or turn-off can be realized by using the RC-pin. If pin 11
is connected to pin 17 the power modules turns off. Normal
operation is achieved if pin 11 is open (NC). To ensure safe turn-off
the voltage difference between pin 11 and 17 shall be less than
1.0V. RC is an open collector compatible output with a sink
capacity of 1mA (see fig. 1).
PKF 4211A with 51 µH common mode and 10 µH series inductor
Radiated EMS (Electro-Magnetic Fields)
Radiated EMS is measured according to test methods in
IEC Standard publ. 801-3. No deviation outside the VO tolerance
band will occur under the following conditions:
Frequency range
0.01...200 MHz
200...1,000 MHz
1...12 GHz
Voltage level
3 Vrms/m
3 Vrms/m
PKF 4211A I
10 Vrms/m
Conducted EMS
Electro Magnetic Susceptibility is measured by injection of
electrical disturbances on the input terminals. No deviation
outside the VO tolerance band will occur under the following
conditions:
Frequency range Voltage level
Figure 1
30...300 MHz
1.0 Vrms
The signal is amplitude modulated with 1 kHz/80% and applied
in both differential and common mode.
Turn-on/off Input Voltage
The power module monitors the input voltage and will turn on
and turn off at predetermined levels set by means of external resis-
tors.
ESD
Electro Static Discharge is tested according to IEC publ. 801-2.
No destruction will occur if the following voltage levels are applied
to any of the terminal pins:
To increase V a resistor should be connected between pin 11
Ion
and 17 (see fig. 2).
The resistance is given by the following equation:
Test
Voltage level
4 kV
2 kV
For VI>34.5V,
Air discharge
Contact discharge
Riunom=(2655-V )/(V -34.5) kW
I
I
VI is the desired turn-on input voltage. The values are nominal and
apply when the unadjusted module turns on at 34.5V.
EFT
Electrical Fast Transients on the input terminals could affect the
output voltage regulation causing functional errors on the Printed
Board Assembly (PBA). The PKF power modules withstand EFT
levels of 0.5 kV keeping VO within the tolerance band and
2.0 kV without destruction. Tested according to IEC publ. 801-4.
To decrease VIon a resistor should be connected between pin 10
and 11 (see fig. 2). The resistance is given by the following equa-
tion:
For 30.5<V <34.5 V,
I
Rinnom=45×(V -30.5)/(34.5-V ) kW
I
I
Output Ripple & Noise (VOac)
VI is the desired turn-on input voltage. The values are nominal and
apply when the unadjusted module turns on at 34.5V.
Output ripple is measured as the peak to peak voltage of the fun-
damental switching frequency.
6
EN/LZT 146 79 R1A ©Ericsson Microelectronics AB, June 2001
ERICSSON [ ERICSSON ]
