Q2D30ZEBC4
| Model | Q2D30ZEBC4 |
| Description | 2-OUTPUT DC-DC REG PWR SUPPLY MODULE |
| PDF file | Total 13 pages (File size: 196K) |
| Chip Manufacturer | BEL |
Q2D Series – Quarter-Brick DC/DC Converter
48V Input
Dual Output
Data Sheet
0.2 mA at a low level voltage of
≤
0.8 V, and
sourcing up to 0.5 mA at high logic level of 5 V;
higher current capability is required for control
voltages greater than 5 V. See the Start-up
Information section for system timing waveforms
associated with use of the ON/OFF pin.
Output Voltage Adjust /TRIM (Pin 6)
The converter’s output voltages can be adjusted
simultaneously up 10% or down 10% relative to
the rated output voltages by the addition of an
externally connected resistor.
The TRIM pin should be left open if trimming is
not being used. To minimize noise pickup, a 0.1
µF capacitor is connected internally between the
TRIM and RETURN pins.
Application
Input and Output Impedance
These power converters have been designed to
be stable with no external capacitors when used
in low inductance input and output circuits.
However, in many applications, the inductance
associated with the distribution from the power
source to the input of the converter can affect the
stability of the converter. The addition of a 33 µF
electrolytic capacitor with an ESR < 1
Ω
across
the input helps ensure stability of the converter. In
many applications, the user has to use decoupling
capacitance at the load. The converter will exhibit
stable operation with external load capacitance up
to 10,000 µF on 3.3 V and 4,700uF on 5 V output.
ON/OFF (Pin 2)
Vin (+)
Q
The ON/OFF pin is used to turn the power
converter on or off remotely via a system signal.
There are two remote control options available,
positive logic and negative logic and both are
referenced to Vin(-). Typical connections are
shown in Fig. 11.
Vin (+)
Series
Converter
(Top View)
TM
Vout2 (+)
TRIM
RTN
Rload1
R
T-INCR
Rload2
Vin
ON/OFF
Vin (-)
Vout1 (+)
Q
TM
Fig. 12:
Configuration for Increasing Output Voltage.
Vout2 (+)
TRIM
RTN
Rload1
Rload2
Series
Converter
(Top View)
Vin
ON/OFF
Vin (-)
CONTROL
NPUT
Vout1 (+)
To increase the output voltage (refer to Fig. 12), a
trim resistor, R
T-INCR
, should be connected
between the TRIM (Pin 6) and RETURN (Pin 5),
with a value from the table below.
Vin (+)
Q
Fig. 11:
Circuit Configuration for ON/OFF Function.
Series
Converter
(Top View)
TM
Vout2 (+)
TRIM
RTN
Rload1
R
T-DECR
Rload2
The positive logic version turns on when the
ON/OFF pin is at logic high and turns off when at
logic low. The converter is on when the ON/OFF
pin is left open
.
The negative logic version turns on when the pin
is at logic low and turns off when the pin is at logic
high. The ON/OFF pin can be hard wired directly
to Vin(-) to enable automatic power up of the
converter without the need of an external control
signal.
A mechanical switch, open collector transistor, or
FET can be used to drive the input of the ON/OFF
pin. The device must be capable of sinking up to
Rev. JUN 06, 2002
Vin
ON/OFF
Vin (-)
Vout1 (+)
Fig. 13:
Configuration for Decreasing Output Voltage.
To decrease the output voltage, a trim resistor R
T-
DECR
, (Fig. 13) should be connected between the
TRIM (Pin 6) and Vout1(+) pin (Pin 4), with a
value from the table below, where:
Δ
=
percentage
Vout(NOM).
of
increase
or
decrease
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