SBVS313 June 2017 TPS7A85A

PRODUCTION DATA. 

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Pin Configuration and Functions
  6. Specifications
    1. 6.1Absolute Maximum Ratings
    2. 6.2ESD Ratings
    3. 6.3Recommended Operating Conditions
    4. 6.4Thermal Information
    5. 6.5Electrical Characteristics
    6. 6.6Typical Characteristics
  7. Detailed Description
    1. 7.1Overview
    2. 7.2Functional Block Diagram
    3. 7.3Feature Description
      1. 7.3.1Voltage Regulation Features
        1. 7.3.1.1DC Regulation
        2. 7.3.1.2AC and Transient Response
      2. 7.3.2System Start-Up Features
        1. 7.3.2.1Programmable Soft Start (NR/SS)
        2. 7.3.2.2Internal Sequencing
          1. 7.3.2.2.1Enable (EN)
          2. 7.3.2.2.2Undervoltage Lockout (UVLO) Control
          3. 7.3.2.2.3Active Discharge
        3. 7.3.2.3Power-Good Output (PG)
      3. 7.3.3Internal Protection Features
        1. 7.3.3.1Foldback Current Limit (ICL)
        2. 7.3.3.2Thermal Protection (Tsd)
    4. 7.4Device Functional Modes
      1. 7.4.1Regulation
      2. 7.4.2Disabled
  8. Application and Implementation
    1. 8.1Application Information
      1. 8.1.1External Component Selection
        1. 8.1.1.1Adjustable Operation
        2. 8.1.1.2ANY-OUT Programmable Output Voltage
        3. 8.1.1.3ANY-OUT Operation
        4. 8.1.1.4Increasing ANY-OUT Resolution for LILO Conditions
        5. 8.1.1.5Current Sharing
        6. 8.1.1.6Recommended Capacitor Types
        7. 8.1.1.7Input and Output Capacitor Requirements (CIN and COUT)
        8. 8.1.1.8Feed-Forward Capacitor (CFF)
        9. 8.1.1.9Noise-Reduction and Soft-Start Capacitor (CNR/SS)
      2. 8.1.2Start-Up
        1. 8.1.2.1Circuit Soft-Start Control (NR/SS)
          1. 8.1.2.1.1Inrush Current
        2. 8.1.2.2Undervoltage Lockout (UVLO)
        3. 8.1.2.3Power-Good (PG) Function
      3. 8.1.3AC and Transient Performance
        1. 8.1.3.1 Power-Supply Rejection Ratio (PSRR)
        2. 8.1.3.2Output Voltage Noise
        3. 8.1.3.3Optimizing Noise and PSRR
          1. 8.1.3.3.1Charge Pump Noise
        4. 8.1.3.4 Load Transient Response
      4. 8.1.4DC Performance
        1. 8.1.4.1Output Voltage Accuracy (VOUT)
        2. 8.1.4.2 Dropout Voltage (VDO)
          1. 8.1.4.2.1Behavior When Transitioning From Dropout Into Regulation
      5. 8.1.5Sequencing Requirements
      6. 8.1.6Negatively Biased Output
      7. 8.1.7Reverse Current
      8. 8.1.8Power Dissipation (PD)
        1. 8.1.8.1Estimating Junction Temperature
        2. 8.1.8.2Recommended Area for Continuous Operation (RACO)
    2. 8.2Typical Applications
      1. 8.2.1Low-Input, Low-Output (LILO) Voltage Conditions
        1. 8.2.1.1Design Requirements
        2. 8.2.1.2Detailed Design Procedure
        3. 8.2.1.3Application Curves
  9. Power-Supply Recommendations
  10. 10Layout
    1. 10.1Layout Guidelines
    2. 10.2Layout Example

Features

  • Low Dropout: 150 mV (Typical) at 4 A
  • 0.75% (Maximum) Accuracy Over Line, Load, and Temperature With BIAS
  • Output Voltage Noise:
    • 4.4 μVRMS at 0.8-V Output
    • 7.7 μVRMS at 5.1-V Output
  • Input Voltage Range:
    • Without BIAS: 1.4 V to 6.5 V
    • With BIAS: 1.1 V to 6.5 V
  • ANY-OUT™ Operation:
    • Output Voltage Range: 0.8 V to 3.95 V
  • Adjustable Operation:
    • Output Voltage Range: 0.8 V to 5.1 V
  • Power-Supply Ripple Rejection:
    • 40 dB at 500 kHz
  • Excellent Load Transient Response
  • Adjustable Soft-Start In-Rush Control
  • Open-Drain Power-Good (PG) Output
  • Stable with a 47-μF or Larger Ceramic Output Capacitor
  • θJC = 3.4°C/W
  • 3.5-mm × 3.5-mm, 20-Pin VQFN

Applications

  • Digital Loads: SerDes, FPGAs, and DSPs
  • Instrumentation, Medical, and Audio
  • High-Speed Analog Circuits:
    • VCO, ADC, DAC, and LVDS
  • Imaging: CMOS Sensors and Video ASICs
  • Test and Measurement

Description

The TPS7A85A is a low-noise (4.4 μVRMS), low dropout linear regulator (LDO) capable of sourcing 4 A with only 240 mV of maximum dropout. The device output voltage is pin-programmable from 0.8 V to 3.95 V and adjustable from 0.8 V to 5.1 V using an external resistor divider.

The combination of low-noise (4.4 μVRMS), high- PSRR, and high output current capability makes the TPS7A85A ideal to power noise-sensitive components such as those found in high-speed communications, video, medical, or test and measurement applications. The high performance of the TPS7A85A limits power-supply-generated phase noise and clock jitter, making this device ideal for powering high-performance serializer and deserializer (SerDes), analog-to-digital converters (ADCs), digital-to-analog converters (DACs), and RF components. Specifically, RF amplifiers benefit from the high-performance and 5.1-V output capability of the device.

For digital loads (such as application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), and digital signal processors (DSPs)) requiring low-input voltage, low-output (LILO) voltage operation, the exceptional accuracy (0.75% over load and temperature), remote sensing, excellent transient performance, and soft-start capabilities of the TPS7A85A ensure optimal system performance.

The versatility of the TPS7A8500A makes the device a component of choice for many demanding applications.

Device Information(1)

PART NUMBERPACKAGEBODY SIZE (NOM)
TPS7A85AVQFN (20)3.50 mm × 3.50 mm
  1. For all available packages, see the orderable addendum at the end of the data sheet.

Powering RF Components

TPS7A85A Front_AL_SBVS313.gif

Powering Digital Loads

TPS7A85A Typ_app_sch_sbvs313.gif