Test Configurations

Input Reflected-Ripple Current Test Setup

Input reflected-ripple current is measured with a inductor

Lin (4.7uH) and Cin (220uF, ESR < 1.0[ at 100 KHz) to

simulate source impedance.

Capacitor Cin, offsets possible battery impedance.

Current ripple is measured at the input terminals of the

module, measurement bandwidth is 0-500 KHz.

Peak-to-Peak Output Noise Measurement Test

Use a Cout 1.0uF ceramic capacitor.

Scope measurement should be made by using a BNC

socket, measurement bandwidth is 0-20 MHz. Position the

load between 50 mm and 75 mm from the 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.

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 -1V to 1.0V.

A logic high is 2.5V to 100V.

The maximum sink current at the on/off terminal (Pin 4)

during a logic low is -100 uA.

The maximum allowable leakage current of a switch

connected to the on/off terminal (Pin 4) at logic hight (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

change 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 to set the

point as defined in the following equation:

Vadj - Vout

(33*Vout)- (30*Vadj)

Radj-up =

Connecting the external resistor (Radj-down) between the

Trim and +Vout pins decreases the output voltage set point as

defined in the following equation:

Vout-Vadj

(36.667*Vadj) - (33*Vout)

Radj-down =

VDC/ K[

:

Units

Adjusted Output Voltage

:

Vadj

Nominal Output Voltage

:

Vout

Overcurrent Protection

To provide protection in a fault (output overload) condition,

the unit is equipped with internal current limiting circuitry and

can endure current limiting for an unlimited duration. At the

point of current-limit inception, the unit shifts from voltage

control to current control. The unit operates normally once the

output current is brought back into its specified range.

Overvoltage Protection

The output overvoltage clamp consists of control circuitry,

which is independent of the primary regulation loop, that

monitors the voltage on the output terminals.

The control loop of the clamp has a higher voltage set

point than the primary loop.

This provides a redundant voltage control that reduces the

risk of output overvoltage.

The OVP level can be found in the output data.

MPW1000 Series

6

MINMAX

REV:0 2005/04

+Out

-Out

+Vin

-Vin

DC / DC

Converter

Load

Battery

+

Lin

+

Cin

To Oscilloscope

Current

Probe

+Out

-Out

+Vin

-Vin

Dual Output

DC / DC

Converter

Resistive

Load

Scope

Copper Strip

Cout

Com.

Scope

Cout

+Out

-Out

+Vin

-Vin

Single Output

DC / DC

Converter

Resistive

Load

Scope

Copper Strip

Cout

+Out

-Out

+Vin

-Vin

Trim Up

Enable

Trim

Trim Down

10K

Trim

Up/Down