Overview of UCx84xA PWM Controllers
The UCx84xA series by Texas Instruments encompasses a family of current-mode pulse-width modulation (PWM) controllers optimized for off-line and DC-DC converters. These controllers, which are designed to be pin-compatible with the earlier UCx84x series, include various models such as the UC1842A, UC2842A, and UC3842A, among others, differing in aspects like under-voltage lockout (UVLO) thresholds and maximum duty cycles.
Key Features
The datasheet highlights the controllers’ numerous features. These include a low start-up current of less than 0.5mA, a trimmed oscillator for precise discharge current, and automatic feedforward compensation. The controllers also offer pulse-by-pulse current limiting, enhanced load response characteristics, undervoltage lockout with hysteresis, and double pulse suppression. A high-current totem pole output is guaranteed, and the products benefit from an internally-trimmed bandgap reference, supporting up to 500-kHz operation.
Applications
The UCx84xA controllers are suitable for various applications. They extensively serve switch mode power supplies (SMPS), DC-DC converters, power modules, industrial PSUs, and battery-operated PSUs. The controllers are also ideal for custom power design which can be achieved with the aid of Texas Instrument’s WEBENCH Power Designer tool.
Device Information and Variants
These PWM controllers are available in several package formats, including CDIP, LCCC, PLCC, PDIP, and SOIC, with different body sizes corresponding to each model to fit a variety of manufacturing needs. Specific device variants, such as the UC1842A and UC1845A, are designed with particular thresholds for UVLO ON and OFF states and have different duty cycle restrictions, either less than 100% or 50%. The document also specifies that further details about packaging options can be found in the orderable addendum at the datasheet’s end.
Revision Highlights
Recent revisions in the document reflect updates to figures, tables, and correction of equations. There have been changes in operating temperatures for specific series, such as the UC284xA and UC384xA. Furthermore, the datasheet emphasizes additions to the documentation, like the WEBENCH links, and an enhancement of the document structure that now includes new sections on the product’s applications, specifications, and detailed description.
Supporting Documentation and Resources
Table of contents indicates sections on typical applications, layout guidelines, power supply recommendations, and support resources among other related documentation. Texas Instruments offers comprehensive support for their devices, signalling continual updates and feedback methods for documentation, and links to relevant resources for the UCx84xA series in the product folder.
References:
Chat: Powered By VoiceSphere
Pricing & Distributors: https://www.datasheets360.com/part/detail/uc2844ang4/3729777272789088913/
