DAC0808 D/A converter IC: Alternatives, Pinout and Working principle

DAC0808 is a D/A converter IC and is used for converting 8-bit digital data input to analog signal output. It is a monolithic IC featuring a full-scale output current settling time of 150 ns while dissipating only 33 mW with ±5V supplies. 

The chip accuracy of conversion is good and power consumption is also low to make it popular. The power supply currents of the DAC0808 are independent of bit codes and exhibits essentially constant device characteristics over the entire supply voltage range. 

Electronic devices like music players, televisions, mobiles, CD players gaming systems, etc. use this chip for the conversion of audio signals. 

-8 bit parallel digital data input

-Fast settling time (typical value): 150 ns

-Relative accuracy at ±0.19% maximum error

-Full-scale current match: ±1 LSB

-Non-inverting digital inputs are TTL and CMOS compatible

-Power supply voltage range: ±4.5V to ±18V

-Low power consumption: 33 mW@ ±5V

-Maximum power dissipation: 1000 mW

-Operating temperature range: 0ºC to +75ºC

-It is a direct replacement of MC1508/MC1408 IC’s.

Texas Instruments DAC0808LCN/NOPB technical specifications, attributes, parameters and parts with similar specifications to Texas Instruments DAC0808LCN/NOPB.

Due to the advancement in technology, there are microcontrollers available with built-in ADC’s or DAC’s. That’s why we use these IC’s in beginner-level applications. We use this IC generally for Digital to Analog Conversions. 

It takes parallel input in the form of 8-bits. The DAC0808 chip converts this digital input into a current (). We convert this current into an analog voltage by connecting a resistor at the output. The figure below shows a simple circuit that uses DAC0808.

DAC0808 Circuit

We can apply 8-bit digital input to DAC0808 digital inputs pins through any microcontroller like 8051 or PIC etc. The IC changes this input into a current.  We have connected an LF351 operational amplifier to convert this current to voltage. The output voltage obtained through LM351 IC is linearly proportional to the digital inputs. The above circuit is also known as the current to voltage converter as it is converting a current to an analog voltage.

The DAC0808 IC obtains 8-bit input data from two 74LS393 counter ICs. The clock signal connected to the counter IC changes the counter value from 0, 1, 2... to the maximum value on each positive edge of the clock cycle. The digital-to-analog converter IC converts this input data into an analog output voltage.

The output signal amplitude is proportional to the 8-bit input signal and the reference voltage value. However, as you know, the reference voltage is constant in most cases, just like the example circuit above. Therefore, the output signal amplitude mainly depends on the 8-bit digital input of the DAC IC.

-Used in analog and digital circuits

-Used in electrical measurements

-Used in conversion of audio

-Used in hobbyist applications

-Used in radar systems

-Used in military test equipment

-Used in sampling oscilloscopes

-Used in sample and hold circuits

-Used in high-speed integrators

-Used in music players, television, speakers, CD players

Texas Instruments Incorporated (TI) is an American technology company headquartered in Dallas, Texas, that designs and manufactures semiconductors and various integrated circuits, which it sells to electronics designers and manufacturers globally.[6] It is one of the top 10 semiconductor companies worldwide based on sales volume.The company's focus is on developing analog chips and embedded processors, which account for more than 80% of its revenue.TI also produces TI digital light processing technology and education technology products including calculators, microcontrollers and multi-core processors. The company holds 45,000 patents worldwide as of 2016.