PQ60050HZX60 Datasheet, PDF (10/16 Pages) SynQor Worldwide Headquarters – High efficiency, 93% at full rated load current

Applications Section
Input: 35-75V
Output: 5V
Current: 60A
Package: Half-brick
BASIC OPERATION AND FEATURES
This converter series uses a two-stage power conversion topology.
The first stage keeps the output voltage constant over variations in
line, load, and temperature. The second stage uses a transformer
to provide the functions of input/output isolation and voltage step-
down to achieve the low output voltage required.
Both the first stage and the second stage switch 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
significantly less energy than Schottky diodes, enabling the
converter to achieve high efficiency.
Dissipation throughout the converter is so low that it does not
require a heatsink or even a baseplate for operation in many
applications; however, adding a heatsink provides improved thermal
derating performance in extreme situations. To further withstand
harsh environments and thermally demanding applications, certain
models are available totally encased. See Ordering Information
page for available thermal design options.
SynQor half-brick converters use the industry standard footprint
and pin-out.
ON/OFF
ON/OFF
ON/OFF
Vin(^_)
Vin(^_)
Remote Enable Circuit
Negative Logic
(Permanently
Enabled)
ON/OFF
5V
Vin(^_)
Positive Logic
(Permanently
Enabled)
TTL/
CMOS
ON/OFF
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(-).
In negative logic versions, the ON/OFF signal is active low (meaning
that a low voltage turns the converter on). In positive logic versions,
the ON/OFF input is active high (meaning that a high voltage turns
the converter on). Figure A details possible circuits for driving the
ON/OFF pin. Figure B is a detailed look of the internal ON/OFF
circuitry. See Ordering Information page for available enable logics.
REMOTE SENSE Pins 8(+) and 6(-): The SENSE(+) and SENSE(-)
inputs correct for voltage drops along the conductors that connect
the converter’s output pins to the load.
Pin 8 should be connected to Vout(+) and Pin 6 should be connected
to Vout(-) at the point on the board where regulation is desired. 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 9 and 5) to determine when it should trigger,
not the voltage across the converter’s sense leads (Pins 8 and 6).
Therefore, the resistive drop on the board should be small enough
so that output OVP does not trigger, even during load transients.
OUTPUT VOLTAGE TRIM (Pin 7): The TRIM input permits the
user to adjust the output voltage across the sense leads up or down
according to the trim range specifications. SynQor uses industry
standard trim equations.
To decrease the output voltage, the user should connect a resistor
between Pin 7 (TRIM) and Pin 6 (SENSE(–) input). For a desired
decrease of the nominal output voltage, the value of the resistor
should be:
( ) ^100%
Rtrim-down =
Δ% ^{– 2 kΩ}
where
Vin(^_)
Vin(^_)
Open Collector Enable Circuit Direct Logic Drive
Figure A: Various circuits for driving the ON/OFF pin.
18V(max)
5V
50k
ON/OFF
10k
TTL
Vin(^_)
| | ^{Vnominal – Vdesired}
Δ% =
× 100%
Vnominal
To increase the output voltage, the user should connect a resistor
between Pin 7 (TRIM) and Pin 8 (SENSE(+) input). For a desired
increase of the nominal output voltage, the value of the resistor
should be:
( ) _{Rtrim-up =}
Vnominal
1.225
–2
× Vdesired + Vnominal _kΩ
Vdesired – Vnominal
Figure B: Internal ON/OFF pin circuitry
Product # PQ60050HZx60
Phone [phone]
www.synqor.com
Doc.# 005-0005974 Rev. C
12/30/13
Page 10