SLVA824A January   2017  – July 2025 TAS6422-Q1 , TAS6424-Q1 , TAS6424L-Q1 , TPA3111D1-Q1 , TPA3221 , TPA3244 , TPA3245 , TPA3250 , TPA3251 , TPA3255 , TPA3255-Q1

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Overview
  6. 3Schematic and Design
    1. 3.1 Partial Diagnostic Circuits
    2. 3.2 Tuning the Circuit
    3. 3.3 Circuit Parameters
    4. 3.4 Operation
  7. 4Schematic and Bill of Materials
  8. 5Summary
  9. 6Revision History

3.4 Operation

To run the fault diagnostics, this is necessary to drive the SD pin of the device low to initiate shutdown conditions; this makes sure that the amplifier outputs reach a high-Z state. Next, the gate of the N-channel MOSFET must be driven high to activate the diagnostics. The values of the three outputs can then be read to detect any existing fault condition and to diagnose the nature of the fault.

Table 3-5 Logic Table of Fault State Outputs
ConditionOut3Out2Out1
Short to GNDHighLowHigh
Shorted LoadHighHighLow
Short to PVDDLowHighHigh
Open LoadLowLowHigh
No FaultHighHighHigh