SLAAE28A November   2021  – March 2022 DAC43204 , DAC53004 , DAC53204 , DAC53204W , DAC63004 , DAC63204

 

  1.   Design Objective
  2.   Design Description
  3.   Design Notes
  4.   Design Simulations
    1.     Transient Simulation Results
  5.   Register Settings
  6.   Pseudo Code Example
  7.   Design Featured Devices
  8.   Design References

Design Description

This design uses a four-channel buffered voltage or current output low-power smart DAC such as the DAC53004 or DAC63004 (DACx3004) to bias an LED. The smart DAC can be connected in a force-sense configuration with a MOSFET in LED biasing applications needing a few milliamps of current. The DAC will set the source current of the MOSFET and control the amount of current through the LED, connected between the power supply and drain of the MOSFET, by varying the gate voltage. The DAC can be used in current output mode to drive the LED directly with up to 250 µA for low-current LED biasing applications. The VFB pin of the DACx3004 compensates for the gate-to-source voltage (VGS) drop and the drift of the MOSFET when using the MOSFET configuration. The DACx3004s have a general-purpose input-output (GPIO) pin that allows the DAC to enter and exit deep-sleep mode. All register settings can be saved using the non-volatile memory (NVM) on the smart DAC, meaning that the device can be used without a processor, even after a power cycle. This circuit can be used in applications such as barcode scanners, barcode readers, currency counters, POS printers, optical modules, and appliance lighting.