SLUU070A December   2001  – June 2021 TPS62100 , TPS62101 , TPS62102 , TPS62103

 

  1.   Trademarks
  2. 1Features
  3. 2Description
  4. 3Feedback Considerations
    1. 3.1 Error Amplifier
    2. 3.2 Open-Loop Small Signal AC Model
      1. 3.2.1 Open-Loop Small Signal AC Model
  5. 4Operating Instructions
    1. 4.1 Connect a DC Power Supply to Terminal TB1
    2. 4.2 Connect the Load to TB2
    3. 4.3 Place a Jumper on CB2
      1. 4.3.1 Placing a Jumper on CB1 is Optional
    4. 4.4 Turn on the Electronic Load
    5. 4.5 Turn on the Input Power Supply
    6. 4.6 Shut Down the Converter
  6. 5Evaluation Module Layouts
  7. 6Evalulation Module Components
  8. 7References
  9. 8Revision History

2 Description

The TPS62102EVM–01 evaluation module is supplied fully assembled and ready to test. This evaluation module demonstrates an automatic mode switching converter that is capable of 500-mA output current at 3.3 V. The switching frequency of this converter is 1 MHz free running. Other versions of this converter IC are available that have nominal switching frequencies of 300 kHz, 600 kHz, and 2 MHz. Note that the fundamental frequencies have been chosen to minimize interaction with 455-kHz intermediate frequency (IF) circuits. The user needs to supply a power source and suitable load. Figure 2-1 is the schematic of the evaluation module as assembled. In this configuration, the converter should have a closed-loop bandwidth of approximately 40 kHz.

GUID-20210615-CA0I-6G38-Q0GB-DHVFRGCJSQHN-low.gif Figure 2-1 Evaulation Module Schematic

This evaluation module allows user control over the SD/SYNC and MODE pins of the TPS62102. As supplied, the MODE (CB1) pin should be left floating. This allows the TPS62102 to automatically determine whether it operates in the continuous frequency mode or in a pulsed frequency modulation (PFM) mode of operation. See the TPS62102 data sheet for details[1].

The SD/SYNC pin is jumpered to ground by default. This allows the TPS62102 to free run. Do not allow this pin to float, as it causes erratic and unpredictable behavior. To synchronize the converter to an external source, connect the source to the middle pin of CB2. The source should pulse its output at a frequency higher than the free running frequency of the converter. Attempting to synchronize to a lower frequency than this results in erratic behavior. The pulse amplitude should be between 2 V and the VIN supplied to the evaluation module. Do not use a pulse amplitude higher than VIN. Minimum pulse width for syncro- nous signals is 50 ns. This pin can also cause the converter to shut down and enter a low-current mode of operation. To do this, pull the SD/SYNC pin to 2 V or more, and hold it there as long as shutdown is desi- red. Shutdown occurs approximately 20 ms after SD/SYNC is brought high.

GUID-20210615-CA0I-4D1K-ZJRJ-XG86DQVD4NZB-low.gif Figure 2-2 Gain/Phase Response for the Internal Error Amplifier