LT2611UXC データシートと価格 | pdf

LT2611UXC

The LT2611UXC from Analog Devices is a high-speed, precision DAC—perfect if you need accurate analog signal control. It gives you 12-bit resolution, ideal for precise analog tasks. The SPI interface means hooking it up to your MCU or FPGA is super straightforward, and its wide voltage range (2.7 to 5.5V) suits most systems. The DAC outputs buffered rail-to-rail voltage, so you can directly drive your analog circuits without extra amplifiers. Plus, it’s really fast, great for high-frequency applications. Another cool thing is its ultra-low standby current, making it ideal for battery-powered portable devices. Usually comes in compact MSOP or DFN packages. The “UXC” marking indicates industrial-grade quality, supporting temperatures from -40°C up to +85°C—reliable even in tough industrial environments.

LT2611UXC Equivalent Precision Op Amp

If you’re out of LT2611UXC chips, try using MCP4921—it’s basically plug-and-play with identical packaging, voltage, and SPI interface, plus it’s cost-effective. But if you’re after higher precision, say for waveform generation or fine voltage adjustments, consider the AD5662BRMZ with its 16-bit resolution for smoother outputs. Watch out for DAC7571 though: despite similar voltage and packaging, it uses I²C instead of SPI and runs slower (max 400kHz). So, if your project’s already SPI-based or needs faster updates, DAC7571 won’t be suitable without major changes to your setup.

LT2611UXC Amplifier Circuit Example

This circuit is pretty handy—at the bottom left you’ve got your precision DAC, like the LT2611UXC you’re using, outputting accurate voltages controlled via SPI. That voltage goes straight into the positive input of the op-amp. The op-amp drives a transistor, boosting the current to handle bigger loads. The transistor’s output voltage feeds back through resistors into the negative input, so the op-amp adjusts itself to keep the output precise. A compensation capacitor is included to avoid oscillations. It’s a clear, straightforward setup—perfect if you’re driving heavy loads or need precise, high-current output from a DAC.

LT2611UXC Signal Conditioning Circuit

Take a look at this circuit—you’ve got your familiar DAC on the left, like the LT2611UXC (a precise 12-bit model), feeding accurate voltages straight into the op-amp’s positive input. The op-amp buffers and amplifies your signal, using resistors R1, R2, and capacitor C1 for stable feedback, which helps keep everything smooth and avoids oscillations. At the output (VOUT), you can easily drive loads like resistors or current sources, far better than using DAC output directly. It’s your standard DAC with signal conditioning, great for analog control or stable voltage/current outputs.

LT2611UXC High Speed Buffer Design

When you’re working with the LT2611UXC for high-speed outputs, sometimes it struggles driving heavy or fast loads directly, causing distortion or delays. To fix this, consider adding a high-speed buffer op-amp afterward—something like OPA354, THS4281, or AD8065. They’re fast enough not to slow down your DAC’s performance. Put a small resistor (around 10–100Ω) at the input to protect the DAC output current, and another resistor at the buffer’s output to prevent oscillations, especially when connecting ADCs or cables. Also, adding decoupling caps (0.1μF and 10μF) near the op-amp power pins helps cut down high-frequency noise. This setup keeps your high-speed DAC output clean, stable, and accurate.

LT2611UXC Low Noise Application

If you’re using the LT2611UXC for precision tasks like audio or sensor bias, you’ll want your signals super clean—no noise or ripples messing things up. Try buffering the DAC output with a low-noise op-amp, such as OPA211 or LT1028, set as a unity-gain follower to keep your output pure. For power, don’t rely directly on basic regulators; add a low-noise LDO like LT3042, plus some decoupling caps. If you don’t need super-high speeds, adding an RC low-pass filter (say 1kΩ resistor plus 0.1μF capacitor) helps smooth things even further. Also, keep digital and analog grounds separate, and your output lines short, to avoid unwanted interference.