Understanding Remote Sensing in LDO Voltage Regulators

Remote Sensing in LDO Voltage Regulators is a technique that measures and regulates voltage directly at the load, offering a more accurate approach compared to measuring at the regulator's output. This method effectively addresses voltage drops caused by wire resistance or inductance, which are common in systems with long wires or narrow PCB traces. For instance, a 150 mm wire can experience a voltage drop of 97.4 mV at 10 mA without remote sensing, but with this method, the drop is significantly reduced to 19.6 mV. By ensuring precise voltage delivery, Remote Sensing in LDO Voltage Regulators is crucial for precision circuits and high-power systems. Popular LDO models, such as Texas Instruments' TPS7A4700 and Analog Devices' ADP7104, utilize this technology to enhance performance in automotive, industrial, and medical applications. For those seeking reliable solutions, keepbooming;LDO Voltage Regulators Distributors provide access to these advanced regulators, ensuring optimal performance across various systems.

Key Takeaways

• Remote sensing makes voltage more accurate by checking it at the load.

• It helps prevent voltage drops caused by resistance in wires.

• This method is important for systems with high currents or sensitive parts.

• It ensures these systems get the right amount of voltage.

• Remote sensing can save space and money by using fewer big capacitors.

• To work well, sense wires should be near the load.

• Good ground connections are also needed for the best results.

• Popular LDOs like TPS7A4700 and ADP7104 use this method.

• These models improve performance in many different uses.

What Is Remote Sensing in LDO Voltage Regulators?

Challenges in Voltage Regulation

Voltage regulation can be tricky due to wire resistance and inductance. These issues cause voltage drops, especially with long wires or thin PCB traces. For example, a 150 mm wire with 202.7 mΩ resistance can drop 97.4 mV at 475 mA without remote sensing. This drop can harm circuits needing precise voltage or high current.

The problem is worse with flexible cables or long PCB traces. These setups have more resistance, causing bigger voltage drops. Without fixing this, the load might not get the right voltage, which can hurt sensitive parts.

Remote Sensing as a Solution

Remote sensing fixes this by checking voltage at the load, not the regulator. It adjusts for drops caused by resistance and inductance, so the load gets the right voltage. For example, with remote sensing, a 150 mm wire's drop goes from 97.4 mV to 19.6 mV at 475 mA.

This method works well in high-current systems and precise circuits. It keeps voltage steady without needing big capacitors, saving money and space. LDO regulators like Texas Instruments' TPS7A4700 and Analog Devices' ADP7104 use remote sensing to improve performance in cars, factories, and medical devices.

Remote sensing keeps voltage stable, even with long wires or flexible cables. It improves load regulation and prevents voltage drops during high current use.

How Does Remote Sensing Work in LDO Regulators?

Setting Up Remote Sense Mode

What the Remote Sense Pin Does

The Remote Sense pin helps keep voltage accurate. It checks the voltage at the load, not at the regulator. This way, it fixes voltage drops caused by wire resistance or inductance. This is very useful for systems with long wires or high current needs. Voltage drops in these systems can hurt performance.

For example, Texas Instruments' TPS7A4700 uses a Remote Sense pin to deliver accurate voltage in cars and factories. Analog Devices' ADP7104 also uses this feature to keep voltage steady in medical tools and RF devices.

Important Electrical Details

When using Remote Sense, designers must check the LDO's specs. The Remote Sense pin has high input impedance. This reduces current draw and avoids affecting the load. Sense wires should be placed near the load. This ensures accurate voltage readings and avoids noise problems.

Here’s a table showing LDO setups with and without Remote Sense:

Real-World Use

Using GPIO1 for Remote Sense

In real setups, GPIO1 can act as an input for the Remote Sense pin. This lets the LDO check the load voltage and adjust output. Tests show better voltage control with GPIO1 for Remote Sense. For example, a 150 mm wire without Remote Sense drops 2.753 V at 475 mA. With Remote Sense, the drop improves to 2.833 V.

Good GND Routing for Best Results

Good GND routing is key for Remote Sense to work well. Designers should use low-impedance ground connections without noise. This helps get accurate voltage readings and keeps the system stable. For example, STMicroelectronics' LD1117 and ROHM's BD7xx series focus on strong GND routing for steady voltage in electronics and cars.

Tip: Always keep sense wires and ground wires close to reduce noise and improve accuracy.

Benefits of Remote Sensing in LDO Voltage Regulators

Better Voltage Control

More accurate for high-current and sensitive circuits.

Remote sensing helps keep voltage steady by checking it at the load. This is very useful for circuits needing exact voltage, like high-current systems. For example, Texas Instruments' TPS7A4700 has very low noise (4.7 μVRMS). It works well in tools that need stable voltage. Analog Devices' ADP7104, with 9 μV RMS noise, is great for medical devices and RF systems.

Fixes voltage drops in long wires or thin traces.

Long wires or narrow PCB traces can cause voltage drops. Remote sensing fixes this by adjusting the voltage at the load. STMicroelectronics' LD1117 series is good for fixing these drops. It is often used in affordable electronics to keep voltage steady.

Saves Space and Money

Less need for big capacitors.

Remote sensing makes load regulation better, so fewer big capacitors are needed. This lowers costs and improves designs. Microchip's MIC5205 works with small capacitors and shows how remote sensing saves space.

Smaller designs save PCB space and cost.

Remote sensing removes the need for extra parts, saving PCB space. Small LDOs like Texas Instruments' TLV733P, with its tiny size (0.8 mm²), are perfect for small gadgets like wearables and phones.

Handles Sudden Voltage Changes

Stops voltage drops during quick load changes.

Quick changes in current can cause voltage to drop. Remote sensing adjusts the voltage fast to keep it steady. ROHM's BD7xx series is made for cars and handles these changes well.

Manages voltage spikes during sudden changes.

Sudden voltage spikes can harm sensitive circuits. Remote sensing fixes this by quickly adjusting the output voltage. Analog Devices' LT1763, with a low dropout of 300 mV at 500 mA, is great for industrial systems needing fast response.

Tip: Place sense wires carefully to reduce noise and improve accuracy.

Startup and Functional Current Limits

Keeping systems stable during startup surges

When devices start, they often need extra current. This can cause a quick voltage drop, which might upset sensitive parts. LDO regulators with remote sensing fix this by checking voltage at the load. They adjust the output to keep things steady during startup.

For example, Texas Instruments' TPS7A2025 uses very little power, just 1 μA. It works well for IoT gadgets that need low power when starting. Analog Devices' LT1763, with a 300 mV drop at 500 mA, is great for factory systems needing stable startups.

Protecting circuits in heavy-use situations

In high-use cases, like cars or factories, circuits need protection from too much current. LDO regulators with remote sensing are perfect here. They keep voltage steady even when the load is heavy by adjusting the output.

For instance, STMicroelectronics' LD1117 series gives fixed 3.3V or 5V and handles 1A. It’s a budget-friendly choice for home electronics. ROHM's BD7xx series, which works with up to 45V input and 500 mA output, is great for car systems. These LDOs show how remote sensing keeps systems safe and stable under heavy use.

Tip: Use LDO regulators with remote sensing for better voltage control and to protect important parts in high-load designs.

Uses of Remote Sensing in LDO Regulators

High-Current Systems

Keeping voltage steady with heavy loads

High-current systems need accurate voltage to stay stable. Remote sensing in LDO regulators helps by fixing voltage drops from heavy loads. For example, Texas Instruments' TPS7A4700 works well for cars and factories. It handles 36V input and 500mA output. Its low noise of 4.7 μVRMS makes it great for tools needing steady voltage.

Test results showing better voltage control

Tests show how remote sensing improves voltage under heavy loads. These tests copy real-world situations where current changes a lot. Key findings include:

• Output voltage stabilizes faster during load changes.

• Voltage drops less across long wires or traces.

For example, Analog Devices' ADP7104 has ultra-low noise of 9 μV RMS. It handles 500mA output and works well in medical tools and RF systems.

Systems with Long Wires or Traces

Fixing voltage drops in long cables

Long wires or flat cables can cause voltage drops due to resistance. Remote sensing checks voltage at the load to fix this. It keeps voltage steady even with long wires. STMicroelectronics' LD1117 series is a good choice for this. It gives fixed 3.3V or 5V outputs at 1A and works well in home electronics.

Test data for long wires with and without remote sensing

Tests show how remote sensing reduces voltage drops in long wires. For example, a 150mm wire without remote sensing drops 97.4mV at 475mA. With remote sensing, the drop is only 19.6mV. This helps systems with long wires work better.

Precision Analog Circuits

Why accurate voltage matters for sensitive parts

Sensitive circuits need very accurate voltage to work well. Remote sensing keeps voltage steady even when loads change. For example, ROHM's BUxxJA2MNVX has ultra-low noise of 30 μVrms. It handles 200mA output and is great for audio devices needing stable voltage.

Best setups for precision systems

Precision systems use LDOs with low noise and high accuracy. Texas Instruments' TLV733P is very small (0.8mm²) and adjustable from 1.2-5V. It’s perfect for phones and wearables. Microchip's MIC5205 works with small capacitors and is reliable for car electronics.

Remote sensing in LDO regulators improves voltage control, helping many different systems stay stable.

Remote sensing in LDO voltage regulators helps modern electronics work better. It keeps voltage accurate by fixing drops from resistance and inductance. This is very useful in high-current systems or with long wires. Devices like Texas Instruments' TPS7A4700 are great for precise tools. Analog Devices' ADP7104 works well in medical machines.

To get the best results, setup must be done carefully. Designers should place sense wires close to the load. They also need low-impedance ground connections to keep things stable. By solving voltage problems at the load, remote sensing is useful in many areas, like cars and wearable gadgets.

What does remote sensing do in LDO voltage regulators?

Remote sensing helps deliver the right voltage to the load. It fixes voltage drops caused by wire resistance and inductance. This is very important for devices needing exact voltage, like medical tools, car systems, and factory machines.

How does remote sensing make circuit designs better?

Remote sensing makes circuits simpler by reducing the need for big capacitors. This saves space on the PCB and lowers costs. For example, Microchip's MIC5205 works well with small capacitors, making it great for car electronics.

Which LDO regulators work well for high-current systems?

Texas Instruments' TPS7A4700 and Analog Devices' ADP7104 are good for high-current systems. The TPS7A4700 handles 500mA with very low noise. The ADP7104 also supports 500mA and has low noise, making it great for medical tools and RF devices.

Can remote sensing help devices that use batteries?

Yes, remote sensing improves voltage control in battery-powered devices. It reduces energy waste and keeps power delivery efficient. STMicroelectronics' STLQ020 uses very little power, just 0.8μA, making it perfect for battery gadgets.

Why is remote sensing useful for sensitive circuits?

Sensitive circuits need steady and accurate voltage to work well. Remote sensing checks voltage at the load to keep it stable. ROHM's BUxxJA2MNVX, with very low noise, is great for audio devices and other delicate systems.

See Also

Understanding The IRF820 MOSFET For Power Management Applications

Unveiling The LPQ252-CEF For Superior Power Management

Reasons To Select Coilcraft XPL2010 For VRM Solutions

Analyzing MC9S12DJ256MFUE Specs For Automotive Use

A Simple Guide To Integrate SN74LVC4245APW Sensors