Controlled Baseline

– One Assembly/Test Site, One Fabrication

Site

Extended Temperature Performance of

–40°C to 105°C

Enhanced Diminishing Manufacturing

Sources (DMS) Support

Enhanced Product Change Notification

Qualification Pedigree†

Precision 1% Reference

Over-Current Sense Threshold Accurate to

5%

Programmable Duty-Ratio Over-Current

Protection

4.5 V to 36 V Operation

100 mA Output Drive, Source or Sink

Under-Voltage Lockout

Adjustable Current Limit to Current Sense

Ratio

Separate +VIN terminal

Programmable Driver Current Limit

Access to VREF and E/A(+)

Logic-Level Disable Input

description

The UC2832 series of precision linear regulators include all the control functions required in the design of very

low dropout linear regulators. Additionally, they feature an innovative duty-ratio current limiting technique which

provides peak load capability while limiting the average power dissipation of the external pass transistor during

fault conditions. When the load current reaches an accurately programmed threshold, a gated-astable timer is

enabled, which switches the regulator’s pass device off and on at an externally programmable duty-ratio. During

the on-time of the pass element, the output current is limited to a value slightly higher than the trip threshold

of the duty-ratio timer. The constant-current-limit is programmable on the UC2832 to allow higher peak current

during the on-time of the pass device. With duty-ratio control, high initial load demands and short circuit

protection may both be accommodated without extra heat sinking or foldback current limiting. Additionally, if the

timer pin is grounded, the duty-ratio timer is disabled, and the IC operates in constant-voltage/constant-current

regulating mode.

These IC’s include a 2 Volt (±1%) reference, error amplifier, UVLO, and a high current driver that has both source

and sink outputs, allowing the use of either NPN or PNP external pass transistors. Safe operation is assured

by the inclusion of under-voltage lockout (UVLO) and thermal shutdown.