UCD3138RGCT

Overview

The UCD3138RGCT is a highly integrated digital power controller from Texas Instruments, designed for isolated power conversion applications. It features a 32-bit ARM7TDMI-S processor operating at 31.25MHz and includes up to 32KB of program flash with ECC support. The device incorporates an error ADC (EADC) with a sampling rate of up to 16MHz and configurable resolution down to 1mV/LSB. It provides up to eight high-resolution digital pulse-width modulated (DPWM) outputs with 250ps pulse width resolution. The component operates within a supply voltage range of 3V to 3.6V and supports a working temperature range from -40°C to +125°C. It is housed in a 64-pin VQFN package.

Feature Summary

• Supports digital control of up to three independent feedback loops using dedicated PID hardware with configurable two-pole/two-zero compensation.
• Integrates a high-speed error ADC capable of 16MHz sampling with adaptive sample positioning and hardware-based averaging.
• Enables non-shutdown firmware updates through dual memory image support, allowing execution from one bank while programming another.
• Includes multiple communication interfaces such as I2C/PMBus and UART for system configuration and monitoring.

Applications

• Server power supplies
• Telecommunications rectifiers
• High-power DC/DC modules
• Industrial power systems

Procurement Notes

Verify the specific suffix RGCT against the manufacturer datasheet to confirm pinout compatibility and flash capacity. Ensure the design accounts for moisture sensitivity level requirements during storage and handling. Confirm that the 64-VQFN package dimensions align with the target PCB footprint. Validate that the selected firmware supports the specific peripheral configurations required for the intended power topology.

Selection Notes

Select this component when designing isolated power converters requiring multi-loop digital control without external compensators. It is suitable for applications needing high switching frequencies up to 2MHz and precise phase shifting. Consider this part for designs requiring flexible modulation modes like frequency modulation or phase-shift PWM. Evaluate the need for on-the-fly firmware updates if field upgrades are anticipated.

Part Context

The UCD3138RGCT belongs to the UCD3138 family of digital power controllers. This series integrates a microcontroller core with specialized analog front-ends and digital pulse-width modulators. The family offers various flash capacities and package options to accommodate different complexity levels in power management designs. It represents a shift from traditional analog controllers to fully programmable digital solutions.

Replacement Considerations

Check the UCD3138RGCR for identical functionality in cut-tape packaging. Verify UCD3138ARGCT for potential A-series revisions with updated specifications. Consult the official TI substitution guide for any discontinued variants within the UCD3138 family.