1 Features
• Digital Control of up to 3 Independent Feedback
Loops
– Dedicated PID-Based hardware
– 2-Pole/2-Zero Configurable
– Nonlinear Control
• Up to 16 MHz Error Analog-to-Digital Converter
(EADC)
– Configurable Resolution as Small as 1mV/LSB
– Automatic Resolution Selection
– Up to 8x Oversampling
– Hardware-Based Averaging (up to 8x)
– 14-Bit Effective Digital-to-Analog Converter
(DAC)
– Adaptive Sample Trigger Positioning
• Up to 8 High Resolution Digital Pulse Width
Modulated (DPWM) Outputs
– 250-ps Pulse Width Resolution
– 4-ns Frequency Resolution
– 4-ns Phase Resolution
– Adjustable Phase Shift Between Outputs
– Adjustable Dead-band Between Pairs
– Cycle-by-Cycle Duty Cycle Matching
– Up to 2-MHz Switching Frequency
• Configurable PWM Edge Movement
– Trailing Modulation
– Leading Modulation
– Triangular Modulation
• Configurable Feedback Control
– Voltage Mode
– Average Current Mode
– Peak Current Mode Control
– Constant Current
– Constant Power
• Configurable Modulation Methods
– Frequency Modulation
– Phase Shift Modulation
– Pulse Width Modulation
• Fast, Automatic, and Smooth Mode Switching
– Frequency Modulation and PWM
– Phase Shift Modulation and PWM
• High Efficiency and Light Load Management
– Burst Mode
– Ideal Diode Emulation
– Synchronous Rectifier Soft On/Off
– Low IC Standby Power
• Soft Start / Stop with and without Prebias
• Fast Input Voltage Feed Forward Hardware
• Primary Side Voltage Sensing
• Copper Trace Current Sensing
• Flux and Phase Current Balancing for Nonpeak
Current Mode Control Applications
• Current Share Bus Support
– Analog Average
– Master and Slave
• Feature Rich Fault Protection Options
– 7 High-Speed Analog Comparators
– Cycle-by-Cycle Current Limiting
– Programmable Fault Counting
– External Fault Inputs
– 10 Digital Comparators
– Programmable Blanking Time
• Synchronization of DPWM Waveforms Between
Multiple UCD3138 family devices
• 14-Channel, 12-Bit, 267-ksps General-Purpose
ADC with Integrated
– Programmable Averaging Filters
– Dual Sample and Hold
• Internal Temperature Sensor
• Fully Programmable High-Performance 31.25
MHz, 32-Bit ARM7TDMI-S™ Processor
– 32KB of Program Flash
– 2KB of Data Flash with ECC
– 4KB of Data RAM
– 4KB of Boot ROM Enables Firmware Boot-Load
in the Field via I2C or UART
• Communication Peripherals
– I2C/PMBus
– 2 UARTs on UCD3138RGC (64-Pin QFN)
– 1 UART on UCD3138RHA/UCD3138RMH
(40-Pin QFN) and UCD3138RJA (40-Pin
VQFN)
• Timer Capture with Selectable Input Pins
• Up to 5 Additional General Purpose Timers
• Built In Watchdog: BOD and POR
• 64-Pin QFN and 40-Pin QFN Packages
• Operating Temperature: –40°C to 125°C
• Fusion Digital Power Studio GUI Support

2 Applications
• Power Supplies and Telecom Rectifiers
• Power Factor Correction
• Isolated DC-DC Modules

3 Description
The UCD3138 is a digital power supply controller offering superior levels of integration and performance in a
single-chip solution. The flexible nature of the UCD3138 makes it suitable for a wide variety of power conversion
applications. In addition, multiple peripherals inside the device have been specifically optimized to enhance the
performance of AC-DC and isolated DC-DC applications and reduce the solution component count in the IT and
network infrastructure space.
The UCD3138 controller is a fully programmable solution offering customers complete control of their
application, along with ample ability to differentiate their solution. At the same time, TI is committed to simplifying
our customers' development effort by offering best-in-class development tools, including application firmware,
Code Composer Studio™ software development environment, and TI’s power development GUI which lets
customers configure and monitor key system parameters.
At the core of the UCD3138 controller are the digital control loop peripherals, also known as Digital Power
Peripherals (DPPs). Each DPP implements a high-speed digital control loop consisting of a dedicated Error
Analog-to-Digital Converter (EADC), a PID-based 2-pole/2-zero digital compensator and DPWM outputs with
250-ps pulse width resolution. The device also contains a 12-bit, 267-ksps general-purpose ADC with up to 15
channels, timers, interrupt control, PMBus, and UART communications ports. The device is based on a 32-bit
ARM7TDMI-S RISC microcontroller that performs real-time monitoring, configures peripherals, and manages
communications. The ARM microcontroller executes its program out of programmable flash memory as well as
on-chip RAM and ROM.
In addition to the FDPP, specific power management peripherals have been added to enable high efficiency
across the entire operating range, high integration for increased power density, reliability, and lowest overall
system cost and high flexibility with support for the widest number of control schemes and topologies. Such
peripherals include: light load burst mode, synchronous rectification, LLC and phase-shifted full bridge mode
switching, input voltage feed forward, copper trace current sense, ideal diode emulation, constant current
constant power control, synchronous rectification soft on and off, peak current mode control, flux balancing,
secondary side input voltage sensing, high-resolution current sharing, hardware-configurable soft start with pre
bias, as well as several other features. Topology support has been optimized for voltage mode and peak current
mode controlled phase-shifted full bridge, single and dual phase PFC, bridgeless PFC, hard-switched full bridge
and half bridge, and LLC half bridge and full bridge.