PQ60150EKXXX Datasheet, PDF (11/15 Pages) SynQor Worldwide Headquarters – Thermal shutdown protects converter from abnormal environmental conditions

Technical Specification
Input: 35-75V
Output: 15V
Current: 3.3A
Part No.: PQ60150EKx03
BASIC OPERATION AND FEATURES
The single stage power converter switches at a fixed
frequency for predictable EMI performance. Rectification of
the transformer’s output is accomplished with synchronous
rectifiers. These devices, which are MOSFETs with a very low
on-state resistance, dissipate far less energy than Schottky
diodes. This is the primary reason that the PowerQor
converter has such high efficiency, even at very low output
voltages and very high output currents.
Dissipation throughout the converter is so low that it does
not require a heatsink for operation. Since a heatsink is not
required, the PowerQor converter does not need a metal
baseplate or potting material to help conduct the dissipated
energy to the heatsink. The PowerQor converter can thus be
built more simply and reliably using high yield surface mount
techniques on a PCB substrate.
The PowerQor series of eighth-brick, quarter-brick and half-
brick converters uses the industry standard footprint and
pin-out configuration.
CONTROL FEATURES
REMOTE ON/OFF (Pin 2): The ON/OFF input, Pin 2, permits
the user to control when the converter is on or off. This input is
referenced to the return terminal of the input bus, Vin(-). There
are two versions of the converter that differ by the sense of the
logic used for the ON/OFF input.
In the positive logic version, the ON/OFF input is active high
(meaning that a high turns the converter on). In the negative
logic version, the ON/OFF signal is active low (meaning that a
low turns the converter on). Figure A details five possible circuits
for driving the ON/OFF pin. Figure B is a detailed look of the
internal ON/OFF circuitry.
REMOTE SENSE(+) (Pins 7 and 5): The SENSE(+) inputs
correct for voltage drops along the conductors that connect the
converter’s output pins to the load.
Pin 7 should be connected to Vout(+) and Pin 5 should be
connected to Vout(-) at the point on the board where regulation
is desired. A remote connection at the load can adjust for a
voltage drop only as large as that specified in this datasheet,
that is
[Vout(+) - Vout(-)] – [Vsense(+) - Vsense(-)] <
Sense Range % x Vout
Pins 7 and 5 must be connected for proper regulation of
the output voltage. If these connections are not made, the
converter will deliver an output voltage that is slightly higher
than its specified value.
Note: the output over-voltage protection circuit senses the
voltage across the output (pins 8 and 4) to determine when
it should trigger, not the voltage across the converter’s sense
leads (pins 7 and 5). Therefore, the resistive drop on the board
should be small enough so that output OVP does not trigger,
even during load transients.
ON/OFF
ON/OFF
ON/OFF
Vin(_)
Remote Enable Circuit
Vin(_)
Vin(_)
Negative Logic
Positive Logic
(Permanently Enabled) (Permanently Enabled)
ON/OFF
5V
TTL/
CMOS
ON/OFF
Vin(_)
Open Collector Enable Circuit
Vin(_)
Direct Logic Drive
Figure A: Various circuits for driving the ON/OFF pin.
ON/OFF
Vin(^_)
10k
50k
100pF
5V
TTL
Figure B: Internal ON/OFF pin circuitry
Product # PQ60150EKx03
Phone [phone]
www.synqor.com
Doc.# 005-0005265 Rev. A
08/20/09
Page 11