DAC1282: DAC1282 OUTPUT FORMAT PROBLEM

Hi TAI,

Welcome to the TI E2E Forums!

Are you referring to the "SW/TD" pin or the VOUTP/N pins on the DAC1282?

The SW/TD pin is a digital input pin with dual functionality:

1. Switch control - The SW/TD pin can control the integrated switch. Often VOUTP/N is routed to SWINP/N  (as shown in Figure 50) and then the SW/TD pin will determine if the DAC outputs are routed to the SWOUTP/N pins.
   
   
2. Digital data - In this mode the SW/TD acts as a single-bit digital input (bitsteam) that controls the DAC1282's output voltage.
   
   

The VOUTP and VOUTN pins provide the (differential) analog output voltage of the DAC1282. If this output is routed to the integrated switch, then the output of the switch will be this analog signal when the switch is closed.

The format of the bitstream input is the same for the DAC1280 and DAC1282; however, do notice that this bitstream is REQUIRED on the DAC1280 and OPTIONAL on the DAC1282. The DAC1282 has a built-in function generator for generating sine waves, dc voltage, and dc pulses; therefore, the bitstream input is not required for generating these types of signals. Additionally, the DAC1280 outputs a CURRENT, whereas the DAC1282 outputs a VOLTAGE.

I hope that helps! Let me know if that answers your question.

Hi TAI,

Do you mean the "input" to the DAC? The DAC output is an analog signal.
The input is a single bit since there is only one digital input pin (i.e the TDATA pin).

FTI: I'm still looking into your other question, regarding if the digital input has an associated word length for calculating the "1"s density.

Dear sir

since the dac resolution is 24 bits,suppose the clock speed  is 4.096mega ,

1bit data takes (1/4.096mega)*(1/16),if you want to achieve  24bits  resolution

it takes (1/4.096mega)*(1/16)*2^24,quite a long time,there must be some misunderstanding

thanks!!

TAI