WRA-YQD-40&WRB-YQD-40W
Mechanical Specification
Pin
1
2
3,5
4
SINGLE OUTPUT(WRB-YQD-40W)
Assignment
+Vin
-Vin
No pin
CTRL (ON/OFF)
Pin
6
7
8
Assignment
+V
out
-V
out
Trim
DUAL OUTPUT(WRA-YQD-40W)
Pin
1
2
3
Unit:mm
Pin section tolerances:±0.10mm
General tolerances:±0.25mm
4
Assignment
+Vin
-Vin
No pin
CTRL (ON/OFF)
Pin
5
6
7
8
Assignment
+V
out
Common
-V
out
Trim
APPLICATION NOTE
Requirement on output load
In order to ensure the product operate efficiently and reliably,in addition to a
max load(namely full load), a minimum load is specified for this kind of DC/DC
converter.Make sure the specified range of input voltage is not exceeded,the
minimum output load no less than 10% load.If the actual load is less than the
specified minimum load, the output ripple may increase sharply while its
efficiency and reliability will reduce greatly.If the actual output power is very
small,please add an appropriate resistor as extra loading,or contact our
company for other lower output power products.
Recommended Circuit
All the WR-YQD-40W Series have been tested according to the following
recommended testing circuit before leaving factory.This series should be tested
under load(see Figure 1).
If you want to further decrease the input/output ripple,you can increase
capacitance properly or choose capacitors with low ESR.However,the
capacitance of the output filter capacitor must be proper.If the capacitance is
too big,a startup problem might arise.For every channel of output,provided the
safe and reliable operation is ensured,the greatest capacitance of its filter
capacitor sees (Table 1).General:
Cin: 10μF-47μF
Cout: 10μF/100mA
CTRL Terminal
When open or high impedance,the converter work well; When this pin is
′high′;
the converter shutdown; It should be note that the input current (Ic) should
between 5-10mA, exceeding the maximum 20mA will cause permanence
damage to the converter.
The value of R Can be derived as follows :
Input current
While using unstable power source,please ensure the output voltage and ripple
voltage do not exceed indexes of the converter.The preceding power source
must be able to provide for converter sufficient starting current Ip.
General:Ip≤1.6*Iin-max
No parallel connection or plug and play
TYPICAL CHARACTERISTICS
Temperature Derating Graph
AMBIENT TEMPERATURE (℃)
External Output Trimming
ON/OFF Control Pin
CONTROL INPUT.....................................PIN4
CONTROL COMMON................................PIN2
LOGIC COMPATIBILITY......CMOS OR OPEN COLLECTOR TTL
CONTROL VOLTAGE
ON..........................................+5.5VDC min OR OPEN CIRCUIT
OFF......................................+2.5VDC max. OR SHORT TO PIN2
Technical Enquiries-Email:tech@microdc.cn Tel:0086-20-86000646
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