SLAAE33 September   2021 DAC43204 , DAC43401 , DAC43701 , DAC43701-Q1 , DAC53204 , DAC53401 , DAC53701 , DAC53701-Q1 , LM555 , LMC555 , NA555 , NE555 , SA555 , SE555 , TLC555

 

  1.   Trademarks
  2. 1Introduction
  3. 2Functional Overview of 555 Timers vs. Smart DACs
  4. 3Pulse Generator with Variable Frequency and Variable Duty Cycle
  5. 4Analog Input to PWM Output
  6. 5General Purpose Input (GPI) to PWM Output
  7. 6Comparator with Hysteresis
  8. 7Trade-offs and Conclusions

1 Introduction

For decades the 555 timer has enabled system designers to create solutions for a variety of applications, including oscillators, pulse generation, and converting analog signals to pulse width modulated (PWM) signals. Depending on the 555 timer configuration, there can be limits to how flexible the device is in meeting the system designer’s need, whether it be due to the structure of the internal blocks or the tolerances of the external components used to construct the complete circuit.

Texas Instrument’s new family of smart DACs are capable of voltage output configurable waveform generation and include configurable threshold blocks that can be used to exceed the functionality of 555 timer circuits in most cases. The following sections explore a handful of common 555 timer circuits and present the alternative smart DAC solution.