Wall Industries, Inc. 5 Watson Brook Road Exeter, NH 03833

603-778-2300 www.wallindustries.com Fax 603-778-9797

LANK 10W Series

2:1 Wide Input Range

Single and Dual Output

10 Watt DC/DC Converter

DESIGN & FEATURE CONSIDERATONS

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.

In applications where power is supplied over long lines and output loading is high, it may be necessary to use a

capacitor at the input to ensure startup.

By using a good quality low Equivalent Series Resistance (ESR < 1.0Ω at 100kHz) capacitor of 12µF for the 12V

input devices, a 4.7µF for the 24V input devices, and a 2.2µF for the 48V input devices. A capacitor mounted

close to the power module helps ensure stability of the unit.

Maximum Capacitive Load

The LANK 10W Series has a limitation of maximum connected capacitance on the output. The power module

may operate in current limiting mode during start-up, affecting the ramp-up and the startup time. The maximum

capacitance can be found in the “Output Voltage / Current Rating Chart.”

Over Current 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.

Over Voltage Protection

The Output over voltage 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 over voltage.

Thermal Considerations

Many conditions affect the thermal performance of the power module, such as orientation, airflow over the

module, and board spacing. To avoid exceeding the maximum temperature rating of the components inside the

power module, the case temperature must be kept below 95°C. The derating curves are determined from

measurements obtained in an experimental apparatus.