MCH/MGH Single and Dual DC/DC Converters

Crane Aerospace & Electronics Power Solutions

Page 2 of 18

Rev E - 20060508

www.craneae.com

28 VOLT INPUT – 1.5 WATT

Dual models only

Negative

Output

Output

Common

Positive

Output

+

Positive

Input

Inhibit

FB

Shutdown

PWM

Controller

Input

Common

+Vin

+Vout

+

+

Case

Ground

MGH SERIES™ SINGLE & DUAL

DC/DC CONVERTERS

The MGH Series™ of DC/DC converters delivers 1.5 watts of output

power in a labor saving surface mount package. The wide input

voltage range of 12 to 50 VDC accepts the varying voltages of mili-

tary, aerospace, or space applications. Single output converters

feature outputs of 5, 12, or 15 volts while dual output models feature

outputs of ±5, ±12, or ±15 volts. Transient protection of 80 volts for

up to 120 milliseconds exceeds the requirements of MIL-STD-704A

for the 5 and 12 volt single and dual models. The 15 volt single and

dual converters will withstand transients of up to 70 volts for up to

120 milliseconds.

MGH Series DC/DC converters incorporate a continuous flyback

topology with a constant switching frequency of approximately 370

kHz. Output voltage regulation is accomplished on the primary side

using current-mode pulse width modulation (PWM). Regulation is

affected by the output load; refer to the specifications tables for more

information.

For dual output models, up to 80% of the total load may be on one

output providing the other output carries a minimum of 20% of the

total load. The dual models can be used at double the output voltage

by connecting the load between positive and negative outputs,

leaving the common unconnected. As an example the MGH2805D (5

volt dual output) can be used as a 10 VDC output.

When an open collector TTL logic low is applied to the inhibit

terminal, pin 18, the converter shuts down and lowers the output

voltage to near zero and input current to as low 2.3 mA. Leaving the

terminal open or applying an open collector TTL logic high will enable

the converter.

Undervoltage lockout prevents the MGH Series converters from

operating below approximately 8 VDC input voltage to keep system

current levels smooth, especially during initialization or re-start oper-

ations. All models include a soft-start function to prevent large

current draw and minimize overshoot. The MGH Series of converters

also provide short circuit protection by limiting the current to approx-

imately 125% of full load.

MIL-STD-461

Use Interpoint’s FMGA-461 EMI filter to pass the CE03 requirements

of MIL-STD-461C.

MGH DC/DC converters can be surface mounted with pick-and-

place equipment or manually. It is recommended that the case be

attached with flexible epoxy adhesive or silicone which is thermally

conductive (>1 watt /meter/°K).

Internal components are soldered with SN96 (melting temperature

221°C) to prevent damage during reflow. Maximum reflow tempera-

ture for surface mounting the MGH converter is 220°C for a

maximum of 30 seconds. SN60, 62, or 63 are the recommended

types of solder. Hand soldering should not exceed 300°C for 10

seconds per pin.

The hermetically sealed metal cases are available in two different

lead configurations. See case B for dimensions and options.