CMCG Series
30 Watt Single Output
2:1 Input Voltage Range
Rev. B
Chassis Mount DC/DC Converter
DESIGN & FEATURE CONSIDERATIONS
Remote On/Off
Positive logic remote on/off turns the module on during a logic high voltage on the remote on/off pin and off during a logic low. Negative
logic remote on/off turns the module off during a logic low and on during a logic high. To turn the power module on and off, the user must
supply a switch to control the voltage between the on/off terminal and the -Vin terminal. The switch can be an open collector or equivalent.
A logic low is -0.7V to 1.0V.
A logic high is 2.5V to 100V.
The maximum sink current at the On/Off terminal (Pin 3) during a logic low is 100 mA. The maximum allowable leakage current of a switch
connected to the On/Off terminal (Pin 3) at logic high (2.5V to 100V) is 5uA.
Output Voltage Trim
Output voltage trim allows the user to increase or decrease the output voltage set point of a module.
The output voltage can be adjusted by placing an external resistor (Radj) between the Trim and +Vout or -Vout terminals. By adjusting
Radj, the output voltage can be changed by ±10% of the nominal output voltage.
A 10K, 1 or 10 Turn trimpot is usually specified for continuous trimming. Trim pin may be safely left floating if it is not used.
Connecting the external resistor (Radj (up)) between the Trim and -Vout pins increases the output voltage set point as defined by the following
equation:
(33∗ Vout) − (30∗ Vadj
)
R
adj(up)
=
Vadj − Vout
Connecting the external resistor (Radj (down)) between the Trim and +Vout pins decreases the output voltage set point as defined by the
following equation:
(36.667 ∗ Vadj) − (33∗ Vout
)
R
adj(down)
=
Vout − Vadj
Vout:
Vadj:
Units:
Nominal Output Voltage
Adjusted Output Voltage
VDC/KΩ
Input Source Impedance
The power module should be connected to a low ac-impedance input source. Highly inductive source impedances can affect the stability of
the power module.
Wall Industries, Inc. 37 Industrial Drive Exeter, NH 03833
603-778-2300 www.wallindustries.com Fax 603-778-9797
WALL [ WALL INDUSTRIES,INC. ]
