UC3833DW Description

The UC3833DW precision linear regulator comes with every control feature needed for the creation of linear regulators with extremely low dropout rates.

Additionally, they have a cutting-edge duty-ratio current limiting method that limits the average power dissipation of the external pass transistor during fault conditions while still enabling peak load capacity. When the load current hits a precisely defined threshold, a gated-astable timer is enabled, switching the regulator's pass device on and off at an externally programmable duty-ratio. The output current of the pass element is restricted to a value that is just a little bit greater than the duty-ratio timer's trip threshold when it is in operation. On the UCx832, the constant-current-limit can be programmed to enable a larger peak current during the pass device's on-time. High initial load requirements and short circuit protection can both be supported via duty-ratio management without the need for additional heat sinking or foldback current limiting. The duty-ratio timer is also deactivated and the IC runs in constant-voltage/constant-current regulating mode if the timer pin is grounded.

A UVLO, error amplifier, a high current driver with source and sink outputs that enables the use of either NPN or PNP external pass transistors, and a 2 Volt (1%) reference are all included in these ICs. Thermal shutdown and under-voltage lockout (UVLO) are included to ensure safe operation.

The basic functionality of this design are provided by the UC3833 family in a low-cost, 8-pin mini-dip form, while the 14-pin UC2832 series offers greater versatility. Options for packaging include ceramic or plastic (with a N suffix) (J suffix). Commercial (0°C to 70°C), order UC3832/3 (N or J), and industrial (-40°C to 85°C), order UC2832/3, are the specified working temperature ranges (N or J). There is also surface mount packaging available.

UC3833DW Features

• 4.5 V to 36 V Operation

• 100mA Output Drive, Source, or Sink

• Under-Voltage Lockout

• Precision 1% Reference

• Over-Current Sense Threshold Accurate to 5%

• Programmable Duty-Ratio Over-Current Protection

UC3833DW Applications

• Electrical power transmission

• Distribution systems

• Computers and other sensitive electronic devices

• Motor controller circuits

• Driver circuits