PKB 4713 PINB
Operating Information
Input Voltage
Current Limiting
The input voltage range 36...75Vdc meets the
requirements of the European Telecom Standard ETS 300
132-2 for normal input voltage range in -48V and -60V
DC power systems, -40.5...-57.0V and -50.0...-72V
respectively. At input voltages exceeding 75V, the power
loss will be higher than at normal input voltage and T
C
must be limited to absolute max +110
o
C. The absolute
maximum continuous input voltage is 80V DC.
Remote ON/OFF (RC)
All PKB 4000 series DC/DC converters include current
limiting circuitry that allows them to withstand
continuous overloads or short circuit conditions on the
output. The output voltage will decrease towards zero for
output currents in excess of max output current (I
Omax
).
The converter will resume normal operation after removal
of the overload. The load distribution system should be
designed to carry the maximum short circuit output
current specified.
Over Voltage Protection (OVP)
The PKB 4000 series DC/DC converters have two remote
on/off options available. The standard converter is
provided with "negative logic" remote on/off. The
negative logic remote on/off turns the converter off during
a logic high voltage on the on/off pin and on during a
logic low state. The second option is "positive Logic"
remote on/off which can be ordered by adding the suffix
"P" to the end of the part number such as PKB 4613 PIP.
"Positive logic" remote on/off turns the converter on
during a logic high and off during a logic low state.
Standard Remote Control
RC (primary)
Low
Open/High
Module
ON
OFF
Optional (P) Remote Control
RC (primary)
Low
Open/High
Module
OFF
ON
The PKB 4000 series DC/DC converters have latching
output overvoltage protection. In the event of an
overvoltage condition, the converter will shut down. The
converter can be restarted by cycling the input voltage.
Output Voltage Adjust (Trim)
All PKB 4000 series DC/DC converters have an Output
Voltage Adjust pin (Trim). This pin can be used to adjust
the output voltage above or below V
Oi
. When increasing
the output voltage, the voltage at the output pins
(including any remote sensing offset) must be kept below
the overvoltage trip point. Also note that at elevated
output voltages the maximum power rating of the
module remains the same, and the output current
capability will decrease correspondingly. These converters
trim according to the industry standard method.
To decrease V
O
connect R
TRIM-DOWN
from -SENSE to
TRIM
R
TRIM-DOWN
=5.11 100
-
2 kΩ
The remote on/off is referenced to the primary side. A
mechanical switch or an open collector transistor or FET
must be provided between the -V
in
and the remote on/off
inputs to drive the RC inputs to turn the module on and
off.
In situations where it is desired to have the converter
power up automatically without the need for control
signals or a switch, the RC pin can be wired directly to the
-Input circuit on the application board.
Remote Sense
(
∆%
)
To increase V
O
connect R
TRIM-UP
from +SENSE to TRIM
R
TRIM-UP
=5.11 V
O
(100+
∆%
)
1.225
∆%
Output Voltage Trim for 12V
1000000
100000
Adjust Resistor Value (KOhm)
(
(100+2
∆%
) kΩ
∆%
)
The remote sense circuitry will compensate for moderate
amounts of resistance in the distribution system and allow
for voltage regulation at the load or other selected point.
The remote sense lines will carry very little current and do
not need a large cross sectional area. However, the sense
lines on a pcb should be located close to a ground trace or
ground plane. In a discrete wiring situation, the use of
twisted pair wires or other technique to reduce noise
susceptibility is highly recommended.
The converter will compensate for up to 0.5V voltage
drop between the sense voltage and the voltage at the
power module output pins. The output voltage and the
remote sense voltage offset must be less than the
minimum over voltage trip point.
6
10000
1000
100
10
1
0
2
4
6
8
10
12
Decrease
Increase
14
16
18
20
Change In Output Voltage (
∆
)
%
EN/LZT 108 6071 P1D ©Ericsson Inc., Power Modules , February 2003
ERICSSON [ ERICSSON ]
