Ericsson Internal
PRODUCT SPECIFICATION 2 (12)
Prepared (also subject responsible if other) No.
EMQTUWX 3/1301-BMR 629 5118 Uen
Approved Checked Date Rev Reference
EMAOLII 2012-09-26 C
Inhibit Control The products are fitted with
a remote control function
by using the Inhibit/UVLO
pin. The Inhibit control
function allows the product
to be turned on/off by an
external device like a
semiconductor or
mechanical switch. The RC
pin has an internal pull up.
An external pull-up resistor
should never be used with
the inhibit pin.
When the Inhibit pin is left open, the regulator will turn on
when the input voltage is applied. Turn off is achieved by
connecting the Inhibit pin to the GND.
The reference figure abov e shows the typical application of
the inhibit function. The input i s not compatible with TTL logic
device. An open-collector (or open-drain) discrete transistor is
recommended for control. Turning the discrete transistor on
applies a low voltage to the Inhibit control pin and disables the
output of the module. If this device is then turned off, the
module executes a soft-start power-up sequ ence. A regulated
output voltage is produced within 20 ms.
External Decoupling Capacitors
Input capacitors:
The PMR 5118UW requires a minimum input capacitance of e
1000 µF. The ripple current rat ing of the input capacitor must
be at least 600 mA rms. An optional 22 µF X5R/X7R ceramic
capacitor is recommended to reduce RMS ripple current.
The size and value of the input capacitor is determined by the
converter’s transient performance capability. This minimum
value assumes that the converter is supplied with a
responsive, low inductance input source. This sourc e sho uld
have ample capacitive decoupling, and be distributed to the
converter via PCB power and ground planes.
Ceramic capacitors should be located as close as possible to
the module's input pins, within 0.5 inch (1,3 c m). Adding
ceramic capacitance is necessary to reduce the high-
frequency ripple voltage at the module's input. This reduces
the magnitude of the ripple current through the electrolytic
capacitor, as well as the amount of ripple current reflected
back to the input source. Additional ceramic capacitors can be
added to further reduce the RMS ripple current requirement
for the electrolytic capacitor.
The main considerations when selecting input capacitors are
the RMS ripple current rating, temperature stabil ity, and less
than 100 m of equivalent series resista nce (ESR).
Regular tantalum capacitors are not recommended for the
input bus. These capacitors requ ire a recommended minimum
voltage rating of 2× (maximum dc voltage + ac ripple). This is
standard practice to ensure reliability. No tantalum capacitor s
were found with a sufficient voltage rating to meet this
requirement.
Output capacitors:
The PMR 5118UW module requires a minimum output
capacitance of 660µF of polymer-aluminum, tantulum, or
polymer-tantalum type.
The required capacitance above the minimum is determin ed
by actual transient deviation requirements. See
“TurboTrans Technology” information below.
For both input and output capacitors, when the operating
temperature is below 0°C, the ESR of aluminium electrolytic
capacitors increases. For these app lications, OS-CON, poly-
aluminium, and polymer-tantal um types should be considered.
If the TurboTrans feature is not used, minimum ESR and
maximum capacitor limits must be followed. System stability
may be effected and increased output capacitance may be
required without TurboTrans.
When using the PMR 5118UW, observe the minimum ESR of
the entire output capacitor bank. The minimum ESR limit of
the output capacitor bank is 7m.
When using PMR 5118UW without the TurboTrans feature,
the maximum amount of capacitanc e is 1000 µF of ceramic
type. Large amounts of capacitance may reduce system
stability.
Utilizing the TurboTrans feature improves system stability,
improves transient response, and reduces the amount of
output capacitance required to meet system transient design
requirements. For detaile information, see “TurboTrans
Technology” information below .
Output Voltage Adjust (Vadj)
The product has an Output Voltage Adjust function. The
function can be used to adjust the output voltage in the rang e
from 0.7V to 3.6V.
The Vo Adjust control sets the output voltage of the PMR
5118UW. The adjustment me thod requires the addition of a
single external resistor, RSET, that must be connected directly
between pins Vo Adjust (pin 18) an d AGND (pin 4). The value
of the required resistor can be calcul ated using the following
formula.
)()(
k49.6
7.0
O
V
7.0
k1.30
SET
R
Note:
(1) : Use a 0.05 W resistor with a tolerance of 1% and
SET
R
temperature stability of 100 ppm/°C (or better). Connect the
E
PMR 5000 series PoL Regulator
Input 4.5 - 14 V, Output up to 50 A / 180 W
EN/LZT 146 410 R1B March 2013
© Ericsson AB
Technical Specification