SLVSD43C May   2015  – February 2019 TPS7B68-Q1


  1. Features
  2. Applications
  3. Description
    1.     Typical Application Schematic
  4. Revision History
  5. Pin Configuration and Functions
    1.     Pin Functions
  6. Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Switching Characteristics
    7. 6.7 Typical Characteristics
  7. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Device Enable (EN)
      2. 7.3.2 Adjustable Power-Good Threshold (PG, PGADJ)
      3. 7.3.3 Adjustable Power-Good Delay Timer (DELAY)
      4. 7.3.4 Undervoltage Shutdown
      5. 7.3.5 Current Limit
      6. 7.3.6 Thermal Shutdown
      7. 7.3.7 Integrated Watchdog
        1. Window Watchdog (WTS, ROSC, FSEL and WRS)
        2. Standard Watchdog (WTS, ROSC and FSEL)
        3. Watchdog Service Signal and Watchdog Fault Outputs (WD and WDO)
        4. ROSC Status Detection (ROSC)
        5. Watchdog Enable (PG and WD_EN)
        6. Watchdog Initialization
        7. Window Watchdog Operation (WTS = Low)
        8. Standard Watchdog Operation (WTS = High)
    4. 7.4 Device Functional Modes
      1. 7.4.1 Operation With Input Voltage Lower Than 4 V
      2. 7.4.2 Operation With Input Voltage Higher Than 4 V
  8. Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. Input Capacitor
        2. Output Capacitor
        3. Power-Good Threshold
        4. Power-Good Delay Period
        5. Watchdog Setup
      3. 8.2.3 Application Curves
  9. Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Community Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

Pin Configuration and Functions

PWP PowerPAD™ Package
28-Pin HTSSOP With Exposed Thermal Pad
Top View
NC - No internal connection

Pin Functions

DELAY 12 O Power-good delay-period adjustment pin. Connect this pin via a capacitor to ground to adjust the power-good delay time.
EN 4 I Device enable pin. Pull this pin down to low-level voltage to disable the device. Pull this pin up to high-level voltage to enable the device.
FSEL 5 I Internal oscillator-frequency selection pin. Pull this pin down to low-level voltage to select the high-frequency oscillator. Pull this pin up to high-level voltage to select the low-frequency oscillator.
GND 8, 21 G Ground reference
IN 1 I Device input power-supply pin
NC 2, 3, 7, 9, 10, 14, 17, 19, 20, 22, 23, 26, 27 Not connected
OUT 28 O Device 3.3-V or 5-V regulated output voltage pin
PG 24 O Power-good pin. Open-drain output pin. Pull this pin up to VOUT or to a reference through a resistor. When the output voltage is not ready, this pin is pulled down to ground.
PGADJ 25 O Power-good threshold-adjustment pin. Connect a resistor divider between the PGADJ and OUT pins to set the power-good threshold. Connect this pin to ground to set the threshold to 91.6% of output voltage VOUT.
ROSC 11 O Watchdog timer adjustment pin. Connect a resistor between the ROSC pin and the GND pin to set the duration of the watchdog monitor. Leaving this pin open or connecting this pin to ground results in the watchdog reporting a fault at the watchdog output (WDO).
WD 13 I Watchdog service-signal input pin.
WDO 15 O Watchdog status pin. Open-drain output pin. Pull this pin up to OUT or a reference voltage through a resistor. When watchdog fault occurs, this pin is pulled down to a low-level voltage.
WD_EN 16 I Watchdog enable pin. Pull this pin down to a low level to enable the watchdog. Pull this pin up to a high level to disable the watchdog.
WRS 18 I Window ratio selection pin (only applicable for the window watchdog). Pull this pin down to a low level to set the open:closed window ratio to 1:1. Pull this pin up to high level to set the open:closed window ratio to 8:1.
WTS 6 O Watchdog type-selection pin. To set the window watchdog, connect this pin to the GND pin. To set the standard watchdog, pull this pin high.
I = input, O = output, G = ground.