MHV Single, Dual and Triple DC/DC Converters

Crane Aerospace & Electronics Power Solutions

Crane Aerospace & Electronics

Electronics Group (Interpoint Brand)

PO Box 97005 • Redmond WA 98073-9705

425.882.3100 • electronics@craneae.com

www.craneae.com

Page 1 of 14

Rev D - 20060710

28 VOLT INPUT – 15 WATT

DESCRIPTION

Interpoint’s MHV Series™ of DC/DC converters offers a wide input

voltage range of 16 to 50 VDC and a choice of nine different output

voltage configurations comprised of single, dual or triple outputs.

The converters will withstand transients of up to 80 V for up to 120

milliseconds while maintaining output voltages (with the exception of

the 12 volt single and dual outputs which will withstand transients up

to 75 volts and the 15 volt single and dual outputs which will with-

stand up to 60 volts). The MHV Series operates at a full 15 watts of

output power (10 watts for the 3.3 volt single output) over the mili-

tary temperature range of –55°C to +125°C while maintaining low

input and output noise.

MHV Series DC/DC converters are switching regulators that use

continuous flyback conversion topology with a clock frequency of

approximately 600 kHz. MHV Series converters incorporate two

internal converters with one converter phase shifted 180° from the

other to create a dual phase/phase-shifted operation. Each of the

internal converters operates at approximately one-half of the clock

frequency. This proprietary technology eliminates cross regulation,

minimizes input ripple, greatly reduces output ripple and improves

efficiency. On the triple output models, this design provides

completely independent regulation with no cross regulation effect

between the main and auxiliary outputs and no minimum loading

required on the main output.

Open collector TTL levels control the inhibit circuit. The converter is

enabled when the inhibit terminal is left unconnected or when the

inhibit terminal is connected to a voltage between 11.5 and 50 V.

When a low (0.8 V) is applied to the inhibit terminal the converter

shuts down, typically drawing 8.4 mA of input current. Inhibit

terminal resistance is 3.3 k ohms and draws 8.4 mA, typical.

Applying an external signal of 40% to 60% duty cycle and 500 to

700 kHz will synchronize the converter to your system requirements.

Free run clock frequency is approximately 600 kHz. If not used, the

sync terminal must be left unconnected.

Single output converters feature a trim range of as low as 80% to

as high as 110% of Vout nominal, depending on the model. To trim

up, connect a resistor from output common (pin 4) to the trim

terminal (pin 3). To trim down, connect a resistor from the positive

output (pin 5) to the trim terminal (pin 3). See Figure 6 and trim

tables for more information.

An undervoltage lockout of approximately 7 VDC keeps system

current levels low during startup.

Under short circuit conditions of 130% or more of full load current,

the converter will protect itself by shutting down. Short circuit dura-

tion should be brief because power dissipation may cause internal

temperatures to rise rapidly. Restart is automatic upon removal of

the short circuit.

• –55° to +125°C operation

• 16 to 50 VDC input

• Fully Isolated

• Optocoupler feedback

• Fixed switching frequency

600 kHz typical,

• Topology –

Dual Single Ended Flybacks

• 80 V / 120 ms transient protection

(12 Vout single and dual to 75 V,

15 Vout single and dual to 60V)

• Inhibit and sync functions

• Trim on single output models

• Up to 81% efficiency

• Low output noise

MODELS

SINGLE

3.3

5

12

15

DUAL

±5

±12

±15

TRIPLE

+5 & ±12

+5 & ±15