SBVS074N January   2007  – June 2024 TPS74801

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Typical Characteristics: IOUT = 50 mA
    7. 5.7 Typical Characteristics: IOUT = 1 A
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagrams
    3. 6.3 Feature Description
      1. 6.3.1 Enable/Shutdown
      2. 6.3.2 Power Good
      3. 6.3.3 Internal Current Limit
      4. 6.3.4 Thermal Protection
    4. 6.4 Device Functional Modes
      1. 6.4.1 Normal Operation
      2. 6.4.2 Dropout Operation
      3. 6.4.3 Disabled
    5. 6.5 Programming
      1. 6.5.1 Programmable Soft-Start
      2. 6.5.2 Sequencing Requirements
  8. 7 Application and Implementation
    1. 7.1 Application Information
      1. 7.1.1 Adjusting the Output Voltage
      2. 7.1.2 Input, Output, and Bias Capacitor Requirements
      3. 7.1.3 Transient Response
      4. 7.1.4 Dropout Voltage
      5. 7.1.5 Output Noise
    2. 7.2 Typical Applications
      1. 7.2.1 FPGA I/O Supply at 1.5 V With a Bias Rail
        1. 7.2.1.1 Design Requirements
        2. 7.2.1.2 Detailed Design Procedure
        3. 7.2.1.3 Application Curves
      2. 7.2.2 FPGA I/O Supply at 1.5 V Without a Bias Rail
        1. 7.2.2.1 Design Requirements
        2. 7.2.2.2 Detailed Design Procedure
        3. 7.2.2.3 Application Curves
    3. 7.3 Power Supply Recommendations
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
        1. 7.4.1.1 Estimating Junction Temperature
      2. 7.4.2 Layout Example
  9. 8 Device and Documentation Support
    1. 8.1 Device Support
      1. 8.1.1 Device Nomenclature
      2. 8.1.2 Development Support
        1. 8.1.2.1 Evaluation Modules
        2. 8.1.2.2 Spice Models
    2. 8.2 Documentation Support
      1. 8.2.1 Related Documentation
    3. 8.3 Receiving Notification of Documentation Updates
    4. 8.4 Support Resources
    5. 8.5 Trademarks
    6. 8.6 Electrostatic Discharge Caution
    7. 8.7 Glossary
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information

7.1.1 Adjusting the Output Voltage

Figure 7-1 shows the typical application circuit for the TPS748 adjustable output device.

TPS748 Typical Application Circuit for the TPS748 (Adjustable)Figure 7-1 Typical Application Circuit for the TPS748 (Adjustable)

R1 and R2 can be calculated for any output voltage using the formula shown in Figure 7-1. Table 7-1 lists sample resistor values of common output voltages. In order to achieve the maximum accuracy specifications, R2 must be ≤ 4.99 kΩ.

Table 7-1 Standard 1% Resistor Values for Programming the Output Voltage(1)
R1 (kΩ) R2 (kΩ) VOUT (V)
Short Open 0.8
0.619 4.99 0.9
1.13 4.53 1.0
1.37 4.42 1.05
1.87 4.99 1.1
2.49 4.99 1.2
4.12 4.75 1.5
3.57 2.87 1.8
3.57 1.69 2.5
3.57 1.15 3.3
(1) VOUT = 0.8 × (1 + R1 / R2).

 

Note: When VBIAS and VEN are present and VIN is not supplied, this device outputs approximately 50 μA of current from OUT. Although this condition does not cause any damage to the device, the output current can charge up the OUT node if total resistance between OUT and GND (including external feedback resistors) is greater than 10 kΩ.