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  • UCD9081 8-Channel Power Supply Sequencer and Monitor With Error Logging

    • SLVS813C June   2008  – November 2016 UCD9081

      PRODUCTION DATA.  

  • CONTENTS
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  • UCD9081 8-Channel Power Supply Sequencer and Monitor With Error Logging
  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 Recommended Operating Conditions
    3. 6.3 Thermal Information
    4. 6.4 Electrical Characteristics
    5. 6.5 Timing Requirements: I2C Interface
    6. 6.6 Typical Characteristics
  7. 7 Parameter Measurement Information
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Rail Configuration
      2. 8.3.2 Graphical User Interface (GUI)
    4. 8.4 Device Functional Modes
      1. 8.4.1  Power Supply Sequencing
      2. 8.4.2  Power-Supply Enables
      3. 8.4.3  General-Purpose Outputs
      4. 8.4.4  Device Reset
      5. 8.4.5  Voltage Reference
      6. 8.4.6  Voltage Monitoring
      7. 8.4.7  Rail Shutdown
      8. 8.4.8  Alarm Processing
        1. 8.4.8.1 Ignore
        2. 8.4.8.2 Log Only
        3. 8.4.8.3 Retry n Times
        4. 8.4.8.4 Retry Continuously
        5. 8.4.8.5 Sequence
        6. 8.4.8.6 Sequence After Shutdown
      9. 8.4.9  Error Logging
      10. 8.4.10 Brownout
    5. 8.5 Programming
      1. 8.5.1 I2C Interface
      2. 8.5.2 Configuring and Monitoring the UCD9081
      3. 8.5.3 Resetting the Flash Error Log
      4. 8.5.4 Configuring the UCD9081
      5. 8.5.5 User Data
      6. 8.5.6 I2C Address Selection
      7. 8.5.7 I2C Transactions
        1. 8.5.7.1 I2C Unidirectional Transfer
        2. 8.5.7.2 I2C Combined Format
    6. 8.6 Register Maps
      1. 8.6.1  Register Descriptions
      2. 8.6.2  RAIL
      3. 8.6.3  ERROR
      4. 8.6.4  STATUS
      5. 8.6.5  VERSION
      6. 8.6.6  RAILSTATUS
      7. 8.6.7  FLASHLOCK
      8. 8.6.8  RESTART
      9. 8.6.9  WADDR and WDATA
      10. 8.6.10 Reading the FLASH Error Log
  9. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Considerations for MONX Input Series Resistance, RS
      2. 9.1.2 Estimating UCD9081 Reporting Accuracy Over Variations in ADC Voltage Reference
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
      3. 9.2.3 Application Curve
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Documentation Support
      1. 12.1.1 Related Documentation
    2. 12.2 Receiving Notification of Documentation Updates
    3. 12.3 Community Resources
    4. 12.4 Trademarks
    5. 12.5 Electrostatic Discharge Caution
    6. 12.6 Glossary
  13. 13Mechanical, Packaging, and Orderable Information
  14. IMPORTANT NOTICE
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DATA SHEET

UCD9081 8-Channel Power Supply Sequencer and Monitor With Error Logging

1 Features

  • Single Supply Voltage: 3.3 V
  • Low Power Consumption: 3-mA Nominal Supply Current
  • Sequences and Monitors Eight Voltage Rails
  • Rail Voltages Sampled With 3.2-mV Resolution
  • Internal or External Voltage Reference
  • Four Configurable Digital Outputs for Power-On-Reset and Other Functions
  • Configurable Digital Output Polarity
  • Flexible Rail Sequencing Based on Timeline (ms), Parent Rail Regulation Window, or Parent Rail Achieving Defined Threshold
  • Independent Under- and Overvoltage Thresholds Per Rail
  • Configurable Regulation Expiration Times Per Rail
  • Flexible Alarm Processing: Ignore, Log Only, Retry n Times, Retry Continuously, Sequence, Parent Rail Can Shutdown Child Rails
  • Alarm Conditions Logged With Timestamp: Under- and Overvoltage Glitch, Sustained Under- and Overvoltage, Rail Did Not Start
  • On-Chip Flash for Storing User Data
  • Error Logging to Flash for System Failure Analysis
  • I2C™ Interface for Configuration and Monitoring
  • Microsoft Windows™ GUI for Configuration and Monitoring

    • Functional Block Diagram

    UCD9081 fbd_lvs813.gif

2 Applications

  • Telecommunications Switches
  • Servers
  • Networking Equipment
  • Test Equipment
  • Industrial
  • Any System Requiring Sequencing of Multiple Voltage Rails

3 Description

The UCD9081 power-supply sequencer controls the enable sequence of up to eight independent voltage rails and provides four general-purpose digital outputs (GPO). The device operates from a 3.3-V supply, provides 3.2-mV resolution of voltage rails, and requires no external memory or clock. The UCD9081 monitors the voltage rails independently and has a high degree of rail sequence and alarm response options. The sequencing of rails can be based on timed events or on timed events in conjunction with other rails achieving regulation or a voltage threshold. In addition, each rail is monitored for undervoltage and overvoltage glitches and thresholds. Each rail the UCD9081 monitors can be configured to shut down a user-defined set of other rails and GPOs, and alarm conditions are monitored on a per-rail basis.

Figure 20 shows the UCD9081 power-supply sequencer in a typical application.

Device Information(1)

PART NUMBER PACKAGE BODY SIZE (NOM)
UCD9081 VQFN (32) 5.00 mm × 5.00 mm
  1. For all available packages, see the orderable addendum at the end of the data sheet.

Typical Application Diagram

UCD9081 app_dia_lvs813.gif

4 Revision History

Changes from B Revision (December 2010) to C Revision

  • Added ESD Ratings table, Feature Description section, Device Functional Modes, Application and Implementation section, Power Supply Recommendations section, Layout section, Device and Documentation Support section, and Mechanical, Packaging, and Orderable Information sectionGo
  • Deleted Ordering Information table; see POA at the end of the data sheetGo
  • Added Thermal Information tableGo
  • Moved Timing Parameters for I2C Interface table and I2C Timing diagram to SpecificationsGo
  • Moved content in Monitoring the UCD9081 to Register MapsGo

Changes from A Revision (September 2008) to B Revision

  • Added Note 1 to the PIN FUNCTIONS tableGo
  • Added Note regarding state of enable and digital I/O pins when the device contains factory configurationGo
  • Added a reference to the UCD9081 Programming GuideGo

Changes from * Revision (June 2008) to A Revision

  • Changed the data sheet from Product Preview to Production; multiple changes throughoutGo
  • Changed first RAIL voltage equation From: × VREF To: × VR+ Go
  • Changed second RAIL voltage equation From: × VREF To: × VR+ Go

5 Pin Configuration and Functions

RHB Package
32-Pin VQFN
Top View

Pin Functions

PIN(1) I/O DESCRIPTION
NAME NO.
ADDR2/GPO2 26 I/O I2C address select 2, general-purpose digital output 2
ADDR3/GPO3 27 I/O I2C address select 3, general-purpose digital output 3
ADDR4/GPO4 28 I/O I2C address select 4, general-purpose digital output 4
EN1 23 I/O Voltage rail 1 enable (digital output)
EN2 24 I/O Voltage rail 2 enable (digital output)
EN3 11 I/O Voltage rail 3 enable (digital output)
EN4 10 I/O Voltage rail 4 enable (digital output)
EN5 12 I/O Voltage rail 5 enable (digital output)
EN6 13 I/O Voltage rail 6 enable (digital output)
EN7 14 I/O Voltage rail 7 enable (digital output)
EN8/ADDR1/
GPO1		 25 I/O Voltage rail 8 enable (digital output), I2C address select 1, general-purpose digital output 1
MON1 6 I Analog input for voltage rail 1
MON2 7 I Analog input for voltage rail 2
MON3 8 I Analog input for voltage rail 3
MON4 18 I Analog input for voltage rail 4
MON5 19 I Analog input for voltage rail 5
MON6 9 I Analog input for voltage rail 6
MON7 15 I Analog input for voltage rail 7
MON8 16 I Analog input for voltage rail 8
NC 2 — Do not connect
NC 4, 17,
20, 31		 — Recommended to connect to VSS, pin is not connected internally
ROSC 32 — Internal oscillator frequency adjust. Must use 100-kΩ pullup to VCC for minimum drift and maximum frequency when sampling voltage rails.
RST 5 I Reset input
SCL 22 I/O I2C clock. Must pull up to 3.3 V.
SDA 21 I/O I2C data. Must pull up to 3.3 V.
TEST 29 I Connect to VSS
VCC 30 — Supply voltage
VSS 1 — Ground reference
XIN 3 — Connect to VCC
PowerPAD™ — — Package pad. Recommended to connect to VSS.
(1) Enable and GPIO pins are in high-impedance state when a device is received from factory and during the first configuration programming done by customer.

6 Specifications

6.1 Absolute Maximum Ratings

over operating free-air temperature range (unless otherwise noted)(1)
MIN MAX UNIT
Voltage applied from VCC to VSS –0.3 4.1 V
Voltage applied to any pin(2) –0.3 VCC + 0.3 V
ESD diode current at any device terminal ±2 mA
Storage temperature, Tstg –40 85 °C
(1) Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
(2) All voltages referenced to VSS.

6.2 Recommended Operating Conditions

MIN NOM MAX UNIT
VCC Supply voltage during operation and configuration changes 3 3.3 3.6 V
TA Operating free-air temperature –40 85 °C

6.3 Thermal Information

THERMAL METRIC(1) UCD9081 UNIT
RHB (VQFN)
32 PINS
RθJA Junction-to-ambient thermal resistance 32.1 °C/W
RθJC(top) Junction-to-case (top) thermal resistance 18.1 °C/W
RθJB Junction-to-board thermal resistance 6 °C/W
ψJT Junction-to-top characterization parameter 0.2 °C/W
ψJB Junction-to-board characterization parameter 5.9 °C/W
RθJC(bot) Junction-to-case (bottom) thermal resistance 1.2 °C/W
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application report.

6.4 Electrical Characteristics

These specifications are over recommended ranges of supply voltage and operating free-air temperature (unless otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
SUPPLY CURRENT
IS Supply current into VCC TA = 25°C, excluding external current 3 4 mA
IC Supply current during configuration VCC = 3.6 V 3 7 mA
STANDARD INPUTS (RST, TEST)
VIL Low-level input voltage VCC = 3 V VSS VSS + 0.6 V
VIH High-level input voltage VCC = 3 V 0.8 × VCC VCC V
SCHMITT TRIGGER INPUTS (SDA, SCL, EN[1...7], EN8/ADDR1, ADDR[2...4])
VIT+ Positive-going input threshold voltage VCC = 3 V 1.5 1.9 V
VIT– Negative-going input threshold voltage VCC = 3 V 0.9 1.3 V
Vhys Input voltage hysteresis VCC = 3 V, VIT+ – VIT– 0.5 1 V
Ilkg High-impedance leakage current ±50 nA
ANALOG INPUTS (MONx, ROSC)
VCC Analog supply voltage VSS = 0 V 3 3.6 V
VMON<1..8> Analog input voltage Internal voltage reference selected 0 2.5 V
External voltage reference selected
(VCC used as reference)		 0 VCC
CI(1) Input capacitance Only one terminal can be selected at a time (MON1 to MON8) 27 pF
RI(1) Input MUX ON resistance 0 V ≤ VMONx ≤ VCC, VCC = 3 V 2000 Ω
Ilkg High-impedance leakage current MON1 to MON8 ±50 nA
VREF+ Positive internal reference voltage Internal voltage reference selected,
VCC = 3 V		 2.35 2.5 2.65 V
VTUE ADC total unadjusted error VCC = 3 V VR+ = 2.5 V
(internal reference)		 ±12.2 mV
VR+ = VCC
(external reference)		 ±14.7
TREF+(1) Temperature coefficient of internal voltage reference I(VREF+) is a constant in the range of
0 mA ≤ I(VREF+) ≤ 1 mA, VCC = 3 V		 ±100 ppm/°C
MISCELLANEOUS
Tretention Retention of configuration parameters TJ = 25°C 100 Years
POR, BROWNOUT, RESET(4)(5)
td(BOR) Brownout 2000 µs
VCC(start) Brownout dVCC/dt ≤ 3 V/s 0.7 × V(B_IT–) V
V(B_IT–) Brownout dVCC/dt ≤ 3 V/s 1.71 V
Vhys(B_IT–) Brownout dVCC/dt ≤ 3 V/s 70 130 180 mV
t(reset) Brownout Pulse length required at RST pin to accept reset internally, VCC = 3 V 2 µs
DIGITAL OUTPUTS (EN8/GPO1, GPO[2...4], EN[1...7], SDA, SCL)
VOH High-level output voltage IOHmax = –1.5 mA(2), VCC = 3 V VCC – 0.25 VCC V
IOHmax = –6 mA(3), VCC = 3 V VCC – 0.6 VCC
VOL Low-level output voltage IOLmax = 1.5 mA(2), VCC = 3 V VSS VSS + 0.25 V
IOLmax = 6 mA(3), VCC = 3 V VSS VSS + 0.6
Ilkg High-impedance leakage current VCC = 3 V ±50 nA
(1) Not production tested. Limits verified by design.
(2) The maximum total current, IOHmax and IOLmax, for all outputs combined, must not exceed ±12 mA to hold the maximum voltage drop specified.
(3) The maximum total current, IOHmax and IOLmax, for all outputs combined, must not exceed ±48 mA to hold the maximum voltage drop specified.
(4) The current consumption of the brown-out module is already included in the ICC current consumption data.
(5) During power up, device initialization starts following a period of td(BOR) after VCC = V(B_IT–) + Vhys(B_IT–).

6.5 Timing Requirements: I2C Interface

MIN MAX UNIT
tofof Output fall time from VOH to VOL(1) with a bus capacitance from 10 pF to 400 pF 250(2) ns
CI Capacitance for each pin 10 pF
fSCL SCL clock frequency 10 100 kHz
tHD;STA Repeated hold time START condition (after this period, the first clock pulse is generated) 4 µs
tHD;DAT Data hold time 0(3) 3.45(4) µs
tLOW LOW period of the SCL clock 4.7 µs
tHIGH HIGH period of the SCL clock 4 µs
tSU;STA Setup time for repeated start condition 4.7 µs
tSU;DAT Data setup time 250 ns
tr Rise time of both SDA and SCL signals 1000 ns
tf Fall time of both SDA and SCL signals 300 ns
tSU;STO Setup time for STOP condition 4 µs
tBUF Bus free time between a STOP and START condition 4.7 µs
C(b) Capacitive load for each bus line 400 pF
VnL Noise margin at the LOW level for each connected device (including hysteresis) 0.1 × VDD V
VnH Noise margin at the HIGH level for each connected device (including hysteresis) 0.2 × VDD V
(1) See Electrical Characteristics
(2) The maximum tf for the SDA and SCL bus lines (300 ns) is longer than the specified maximum tof for the output stages (250 ns). This allows series protection resistors, Rs , to be connected between the SDA/SCL pins and the SDA/SCL bus lines without exceeding the maximum specified tf.
(3) A device must internally provide a hold time of at least 300 ns for the SDA signal to bridge the undefined region of the falling edge of SCL.
(4) The maximum tHD;DAT must only be met if the device does not stretch the LOW period (tLOW) of the SCL signal.
UCD9081 tim_iface_lvs692.gif Figure 1. Timing Diagram for I2C Interface

6.6 Typical Characteristics

Digital outputs (only one output is loaded at a time)
UCD9081 iol_vol_lvs692.gif Figure 2. Typical Low-Level Output Current
vs Low-Level Output Voltage
UCD9081 ioh_voh_lvs692.gif Figure 3. Typical High-Level Output Current
vs High-Level Output Voltage

 
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