UCD90120 12-Channel Sequencer and System Health Monitor | TI.com

UCD90120 (NRND) 12-Channel Sequencer and System Health Monitor


Not Recommended for New Designs (NRND)

Replaced By UCD90120A – The device has the SAME FUNCTIONALITY and PINOUT as the compared device but is NOT an exact equivalent.

TI does not recommend using this part in a new design. This product continues to be in production to support existing customers.

The most current UCD90xxx PMBus™ Command Reference is available at http://www.ti.com/fusiondocs


The UCD90120 Power Supply Sequencer and System Health Monitor monitors and sequences up to 12 independent voltage rails. The device integrates a 12-bit ADC with a 2.5V internal reference for monitoring up to 13 power supply voltage, current, or temperature inputs.

26 GPIO pins can be used for power supply enables, power-on reset signals, external interrupts, cascading multiple UCD90120 devices, or other system functions. 12 of these pins can be used as PWM outputs for power supply margining or general-purpose PWM functions including clock generation for switch-mode power supplies.

The TI Fusion Digital Power Designer is provided for device configuration. This PC-based Graphical User Interface (GUI) offers an intuitive interface for configuring, storing, and monitoring all system operating parameters.

The UCD90120 has an I2C/PMBus/SMBus communication interface for pre-production and in-system configuring and monitoring and a JTAG Port for production programming.


  • Monitor and Sequence 12 Voltage Rails
    • All Rails Sampled Every 200µs
    • 12-bit ADC With 2.5V, 0.5% Internal VREF
    • Sequence Based on Time, Rail and Pin Dependencies
    • Six Hardware Comparators for Power Supply Fault Response in < 80µs
    • Four Programmable Under-Voltage and Over-Voltage Thresholds per Monitor
    • Programmable Fault Response Including Retries, Shutdown Slaves and Resequence
  • Non-Volatile Error Logging
    • Stores Up To 18 Faults
    • Log Peak Values For All Monitor Inputs
  • Closed Loop Margining for 10 Rails
    • Margin Output Adjusts Rail Voltage to Match User-Defined Margin Thresholds
    • Unused Margin Outputs can be Used as GPIOs or General-Purpose PWM Outputs
  • Watchdog Timer and System Reset
    • Programmable WDT Reset and Start Times
    • Configurable System Reset Pulse Widths
  • Flexible Digital I/O Configuration
    • Boolean Logic Builder for GPO Config
    • GPIOs can be Used as Enables, Resets, Power Good and Other On-Board Functions
  • Wide Range Single Supply (3.3V to 12V)
    • Internal Temperature Sensor
    • 64-Pin QFN Package
  • JTAG and I2C/SMBus/PMBus Interfaces
  • Fusion Digital Power GUI for Configuring and Monitoring Device Operation
    • Industrial / ATE
    • Telecommunications and Networking Equipment
    • Servers and Storage Systems
    • Any System Requiring Sequencing and Monitoring of Multiple Power Rails