Tag Archives: app notes

App note: Paralleling linear regulators made easy

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Various configuration of linear regulator for parallel operation discussed in this technical article from Analog Devices. Link here

Linear regulators provide a simple, low noise solution for dc-dc regulation. However, at higher VIN-VOUT differentials the low efficiency and high power dissipation of linear regulators limits the amount of output current that can realistically be delivered. Connecting multiple linear regulators in parallel spreads the load (and the heat) over several ICs, increasing the useful range of output currents a solution can deliver. However, connecting linear regulators in parallel is not always straightforward.

App Note: Optimizing CAN node bit timing to accommodate digital isolator propagation delays

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Adding robustness by digital isolation and compensating for propagation delays to CAN network presented in this technical article from Analog Devices. Link here (PDF)

Controller area network (CAN), standardized under ISO 11898, is widely used in industrial and automotive applications. CAN protocols such as DeviceNet or CANOpen rely on the built-in error checking and differential signaling. Galvanic isolation can further enhance robustness, offering immunity to high voltage transients at a cost of added propagation delay. The optimal configuration of CAN nodes can allow the maximum data rate and distance even when isolation is present.

App note: Impedance characteristics of bypass capacitor

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App note from ROHM Semiconductors about different type of bypass capacitors impedance and some tip when replacing them. Link here (PDF)

There are various types of capacitors. If you select parts only based on their capacitance values, the requirements for bypass capacitors may not be satisfied, leading to malfunction of devices or nonconformity to standards. This application note focuses on the impedance characteristics of capacitors, and explains cautions for selecting bypass capacitors.

App note: BA1117 dropout voltage

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App note from ROHM Semiconductors about linear regulator dropout voltage. Link here (PDF)

The dropout voltage is the difference between the input and output voltages that is necessary for the stabilizing operation of a linear regulator. When the input voltage approaches the output voltage, stabilizing operation cannot be maintained and the output starts dropping in proportion to the input. The voltage at which this situation starts, i.e., the difference between the input and output voltages that is necessary for the stabilizing operation, is referred to as the dropout voltage.

App note: RS-485 communication link vs. the electric fence, A demonstration of RS-485 EMC robustness

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Analog Devices’ RS-485 robustness demonstration by direct application of HV transient to the communication line. Link here

Industrial and instrumentation applications (I&I) require transmission of data between multiple systems, often over very long distances. The RS-485 bus standard is one of the most widely used physical layer bus designs in I&I applications. Applications for RS-485 include process control networks, industrial automation, remote terminals, and building automation such as heating, ventilation, air conditioning (HVAC), security systems, motor control, and motion control.

In these real systems, lightning strikes, power source fluctuations, inductive switching, and electrostatic discharge can cause damage to communications ports by generating large transient voltages. Designers must ensure that equipment does not just work in ideal conditions but also works in the ‘real world.’

App note: Using ESD diodes as voltage clamps

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App note from Analog Devices on improving robustness of an amplifier by determining and mitigating internal ESD diode clamp electrical overestress. Link here

When external overvoltage conditions are applied to an amplifier, ESD diodes are the last line of defense between your amplifier and electrical over stress. With proper understanding of how an ESD cell is implemented in a device, a designer can greatly extend the survival range of an amplifier with the appropriate circuit design. This article aims to introduce readers to the various types of ESD implementations, discuss the characteristics of each implementation, and provide guidance on how to utilize these cells to improve the robustness of a design.