LM338K

The LM338K is an adjustable positive voltage regulator designed to supply currents in excess of 5A over an output voltage range of 1.2V to 32V. It is exceptionally easy to use, requiring only two resistors to set the output voltage. Careful circuit design ensures outstanding load and line regulation, comparable to many commercial power supplies.

A unique feature of the LM138 family, including the LM338K, is time-dependent current limiting. The current limit circuitry allows peak currents of up to 12A for short durations, enabling the regulator to handle heavy transient loads and speed up start-up under full-load conditions. Under sustained loading, the current limit decreases to a safe value, protecting the regulator. Thermal overload protection and safe area protection for the power transistor are also included.

The LM338K is supplied in a standard TO-3 steel package, suitable for through-hole mounting. It operates within a temperature range of 0°C to 125°C. The device offers adjustable output voltage from 1.2V to 32V and a maximum output current of 5A, with a peak current capability of 7A.

Key electrical specifications include a minimum input voltage of 4.2V and a maximum of 35V. Load regulation is typically 0.1% and a maximum of 0.5%, while line regulation is typically 0.005%/V and a maximum of 0.03%/V. The ripple rejection is typically 75dB.