rev.
page 3 of 3
date 11/2010
PART NUMBER: VWRAS2
DESCRIPTION: dc-dc converter
- Input current
Application Notes:
Noꢀinal input voltage range. The input
current of the power supply ꢀust be sufficient
to the startup current (Ip) of the DC/DC ꢀodule
(Figure 2)
- All of the VWRAS2-SIP Series have been tested
according to the following recoꢀꢀended testing
circuit before leaving the factory. This series should
be tested under load(Figure 8). If you want to further
decrease the input/output ripple, you can increase
capacitance properly or choose capacitors with
low ESR. However, the capacitance should not be too
high(Table 2).
Ip
Table 2
Input Voltage
Range
External Capacitor Table
Input Voltage (V)
Single
Dual
Cout(uF)
Cout(uF)
Vout(VDC)
Vout(VDC)
8.8
5
9
12
15
24
2200
1000
±20
6±0
560
-
-
±5
±9
±12
±15
-
±560
±470
±880
±270
-
- Output Load
In order to ensure the product operates
efficiently and reliably, ꢀake sure the specified range
of input voltage is not exceeded.
470
No parallel connection or plug and play.
Figure 3
Teꢀperature Derating Graph
- NC Terꢀinals
Unless otherwise specified, NC terꢀinals of all series
are used for converter's interior circuit
connection, and are not allowed connection of any
external circuit.
Operating Teꢀp.( C )
-
Reꢀote on/off control (see figure 1)
ON: When control pin (CTRL pin 8) open or Ic
<
0.5ꢀA, converter will have norꢀal output.
OFF: With a 8-10ꢀA input current (Ic) to pin 8, output will be disabled. Under no conditions
should input current (Ic) exceed 20ꢀA. The Value of R in Figure 1 can be derived as follows:
Vc - Vd - 0.65V
Ic
Vc= Voltage at control input
Vd= Diode (D1) voltage drop (.7V voltage drop typical)
Ic= Input Current (5ꢀA recoꢀꢀended disable current)
R=
example 1 : Logic circuit — Apply 5V TTL logic signal on Vc to disable output
5V - 0.7V - 0.65V
Choose 720Ω resistor
R=
= 780 Ω
.005A
example 2 : Short Vin to Vc — Apply 12V on Vc to disable output
12V - 0.7V - 0.65V
R=
= 2180 Ω
Choose 2KΩ resistor
.005A
th
20050 SW 112 Ave. Tualatin, Oregon 97062 phone 503.612.2300 fax 503.612.2383 www.v-infinity.com
