2. No load set point is 5 mV higher than the nominal voltage, to partially compensate voltage drop on the output pins.
3. Load regulation is affected with resistance of the output pins (approximately 0.3 mΩ) since there is no remote sense.
4. Cross regulation is affected with resistance of the RETURN pin (approximately 0.3 mΩ) since there is no remote sense.
MCD10084 Rev. 1.0, 25-Sep-08
Page 3 of 15
www.power-one.com
QD48T025033 DC-DC Converter Data Sheet
36-75 VDC Input; 2.5 and 3.3VDC @ 15A Outputs
Physical Information
Pin Connections
1
2
3
7
TOP VIEW
6
5
4
Pin #
1
2
3
4
5
6
7
•
•
•
•
•
Function
Vin (+)
ON/OFF
Vin (-)
Vout1 (+)
RTN [Vout1(-) and Vout2(-)]
TRIM
Vout2 (+)
SIDE VIEW
All dimensions are in inches [mm]
All pins are Ø 0.040” [1.02] with Ø 0.078”
[1.98] shoulder
Pin Material: Brass
Pin Finish: Tin/Lead over Nickel
Converter Weight: 1 oz [28 g] typical
HT
(Maximum Height)
Height
Option
A
B
C
D
+0.000 [+0.00]
-0.038 [- 0.97]
0.303 [7.69]
0.336 [8.53]
0.500 [12.70]
0.400 [10.16]
CL
(Minimum Clearance)
+0.016 [+0.41]
-0.000 [- 0.00]
0.030 [0.77]
0.063 [1.60]
0.227 [5.77]
0.127 [3.23]
Pin
Option
A
B
C
PL
Pin Length
±0.005 [±0.13]
0.188 [4.77]
0.145 [3.68]
0.110 [2.79]
Converter Part Numbering Scheme
Product
Series
Input
Voltage
Mounting
Scheme
Output
Voltage 1
(V
OUT
1 )
Output
Voltage 2
(V
OUT
2)
ON/OFF
Logic
Maximum
Height
[HT]
Pin
Length
[PL]
Special
Features
QD
Dual
Quarter-
Brick
Format
48
T
025
025
⇒
2.5 V
033
033
⇒
3.3 V
-
N
N
⇒
Negative
P
⇒
Positive
B
A
⇒
0.303”
B
⇒
0.336”
C
⇒
0.500”
D
⇒
0.400”
A
0
36-75 V
Through-
hole
Note: Always specify V
OUT
2 as the
higher of the two output voltages.
A
⇒
0.188”
B
⇒
0.145”
C
⇒
0.110”
0
⇒
STD
The example above describes P/N QD48T025033-NBA0: 36-75 V input, dual output, through-hole mounting, 2.5 V and 3.3 V outputs @ 15 A each, negative
ON/OFF logic, a maximum height of 0.336”, and a through the board pin length of 0.188”. Please consult factory regarding availability of a specific version.
RoHS Ordering Information:
•
•
No RoHS suffix character is required for lead-solder-exemption compliance.
For RoHS compliance to all six substances, add the letter "G" as the last letter of the part number.
MCD10084 Rev. 1.0, 25-Sep-08
Page 4 of 15
www.power-one.com
QD48T025033 DC-DC Converter Data Sheet
36-75 VDC Input; 2.5 and 3.3VDC @ 15A Outputs
Operation
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
both outputs.
ON/OFF (Pin 2)
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. 2.
Vin (+)
depending on the signal polarity. 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. For output voltage 3.3 V, trim up to 10% is
guaranteed only at Vin
≥
40 V, and it is marginal (8% to
10%) at Vin = 36 V.
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.
Family
Converter
TM
Vin (+)
Q
Vout2 (+)
TRIM
RTN
Rload1
R
T-INCR
Rload2
(Top View)
Vin
ON/OFF
Vin (-)
Vout1 (+)
Q
TM
Family
Fig. 3:
Configuration for increasing output voltage.
Vout2 (+)
TRIM
RTN
Rload1
Rload2
Converter
(Top View)
Vin
ON/OFF
To increase the output voltage (refer to Fig. 3), 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.
Family
Converter
TM
Vin (-)
CONTROL
INPUT
Vout1 (+)
Fig. 2:
Circuit configuration for ON/OFF function.
Vin (+)
Q
Vout2 (+)
TRIM
RTN
Rload1
R
T-DECR
Rload2
(Top View)
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.
ON/OFF pin is internally pulled-up to 5 V through a resistor.
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 0.2 mA at a low level
voltage of
≤
0.8 V. An external voltage source of
±20
V max.
may be connected directly to the ON/OFF input, in which
case it should be capable of sourcing or sinking up to 1 mA
MCD10084 Rev. 1.0, 25-Sep-08
Vin
ON/OFF
Vin (-)
Vout1 (+)
Fig. 4:
Configuration for decreasing output voltage.
To decrease the output voltage, a trim resistor R
T-DECR
, (Fig.
4) should be connected between the TRIM (Pin 6) and
Vout1(+) pin (Pin 4), with a value from the table below,