Datasheet

DAC8550

SLAS476E –MARCH 2006–REVISED MARCH 2012

www.ti.com

LAYOUT The power applied to V

should be well-regulated

and low-noise. Switching power supplies and dc/dc

A precision analog component requires careful layout,

converters often have high-frequency glitches or

adequate bypassing, and clean, well-regulated power

spikes riding on the output voltage. In addition, digital

supplies.

components can create similar high-frequency spikes.

This noise can easily couple into the DAC output

The DAC8550 offers single-supply operation and is

voltage through various paths between the power

used often in close proximity with digital logic,

connections and analog output.

microcontrollers, microprocessors, and digital signal

processors. The more digital logic present in the

As with the GND connection, V

should be

design and the higher the switching speed, the more

connected to a 5V power-supply plane or trace that is

difficult it is to keep digital noise from appearing at

separate from the connection for digital logic until

the output.

they are connected at the power-entry point. In

addition, a 1μF to 10μF capacitor and 0.1μF bypass

Due to the single ground pin of the DAC8550, all

capacitor are strongly recommended. In some

return currents, including digital and analog return

situations, additional bypassing may be required,

currents for the DAC, must flow through a single

such as a 100μF electrolytic capacitor or even a Pi

point. Ideally, GND would be connected directly to an

filter made up of inductors and capacitors, all

analog ground plane. This plane would be separate

designed to essentially low-pass filter the 5V supply,

from the ground connection for the digital

removing the high-frequency noise.

components until they were connected at the power-

entry point of the system.

Product Folder Link(s): DAC8550