Texas Instruments UCD9080RHBTG4

Overview

UCD9080RHBTG4 from Texas Instruments is an 8-channel digital power-supply sequencer and monitor IC designed for precise control of voltage rail startup, shutdown, and fault response in complex systems. It operates from a single 3.3-V supply, samples rails every 50 µs with 3.2-mV resolution, supports I²C configuration, and delivers four configurable digital outputs for reset or status signaling - deployed in telecom switches, servers, and networking equipment.

For engineers reviewing the UCD9080RHBTG4 datasheet, UCD9080RHBTG4 pinout, UCD9080RHBTG4 application, or UCD9080RHBTG4 equivalent, key selection considerations include per-rail sequencing logic (time- or parent-rail-triggered), under/overvoltage threshold programmability, rail-dependent shutdown behavior, and compatibility with 3.3-V microcontroller I/O interfaces.

Technical Context

The UCD9080RHBTG4 integrates a 10-bit SAR ADC, I²C slave interface (7-bit address 0x60–0x6F), and programmable sequencing engine that supports three enable trigger modes: fixed delay, parent-rail regulation window, or parent-rail voltage threshold. Each of the eight MON inputs accepts rail voltages via external dividers, with internal 2.5-V or external 3.3-V reference selection affecting sampling accuracy.

Rail monitoring includes sustained UV/OV detection, glitch capture with timestamping, and configurable alarm responses (log, ignore, retry, or sequence-based shutdown). All eight ENx outputs and four GPOs (multiplexed with ADDR pins) support active-high/low polarity and are driven as Schmitt-trigger outputs during normal operation but revert to Schmitt-trigger inputs during RESET for safe default state handling.

Key Specifications

Pinout & Package

The UCD9080RHBTG4 is housed in a 32-pin QFN package (RHB) with 0.5-mm pitch, exposed thermal pad, and RoHS-compliant finish. Pin 1 is located at bottom-left corner when marking side faces up; pin numbering proceeds counterclockwise.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar power-supply sequencing applications.

Compared with UCD9080RHBTG4, UCD90120ARGCT offers greater scalability and protocol flexibility at higher cost and complexity, while TPS659122ZQWR trades monitoring depth and configurability for integration density - making UCD9080RHBTG4 optimal for discrete, high-fidelity sequencing in established 8-rail architectures.

Availability

UCD9080RHBTG4 is available at Aetrix Electronics and suitable for telecom switches, server boards, and networking equipment requiring stable component supply, long-term lifecycle assurance, and consistent parametric performance across production lots.

Supply support for UCD9080RHBTG4 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments is a global semiconductor leader delivering analog, embedded processing, and connectivity solutions for industrial, automotive, and communications markets.

The UCD9080RHBTG4 belongs to TI's UCD power-management IC family, engineered specifically for high-reliability, multi-rail sequencing and monitoring in infrastructure equipment where deterministic power-up, fault containment, and field-serviceable diagnostics are mandatory.

FAQ

What is the primary function of the UCD9080RHBTG4 in a power system?

The UCD9080RHBTG4 serves as an 8-channel digital power-supply sequencer and monitor. Its core function is to enforce precise startup/shutdown timing across multiple voltage rails, detect undervoltage/overvoltage conditions with timestamped logging, and execute configurable responses - including rail-dependent shutdown and GPO assertion. The UCD9080RHBTG4 does not regulate voltage itself but controls external DC/DC converters and LDOs via its ENx outputs.

Does the UCD9080RHBTG4 require an external clock or memory to operate?

No, the UCD9080RHBTG4 operates autonomously without external clock or memory components. It uses an internal oscillator adjusted by the ROSC pin (100-kΩ pullup to VCC) and stores all configuration parameters in nonvolatile memory with 100-year retention. This eliminates BOM additions and simplifies layout - a key design advantage confirmed in the SLVS692E datasheet.

How does the UCD9080RHBTG4 handle I²C address configuration?

The UCD9080RHBTG4 samples the logic states of ADDR1–ADDR4 (pins EN8/ADDR1/GPO1, ADDR2/GPO2, ADDR3/GPO3, ADDR4/GPO4) during device RESET to determine its 7-bit I²C address (0x60–0x6F). External pullup/pulldown resistors are required - the device has no internal bias. After RESET completes, those same pins become configurable GPOs, enabling dynamic reuse without additional GPIOs.

Can the UCD9080RHBTG4 monitor voltage rails above 3.3 V?

Yes, the UCD9080RHBTG4 can monitor rails exceeding 3.3 V using external resistor divider networks on MON1–MON8 inputs. However, the source impedance of the divider must remain below 20 kΩ to maintain the full 20-kHz sampling rate. For rails >3.3 V, the external VCC (3.3 V) reference is used, yielding ±6.8 mV absolute accuracy - verified in the Electrical Characteristics table of SLVS692E.

What happens to ENx and GPO pins during a UCD9080RHBTG4 RESET event?

During RESET - triggered by RST pin assertion, power-on, brownout, or rail-alarm event - all ENx and GPO pins revert to Schmitt-trigger inputs with defined threshold voltages (VIT+ = 1.5–1.9 V, VIT– = 0.9–1.3 V). This ensures predictable default states regardless of external rail sequencing, preventing unintended enable signals. The UCD9080RHBTG4 remains in this state for ~4–5 ms before reasserting configured outputs.