App note: Precautions when measuring the rear of the package with a thermocouple on power devices

App note from ROHM Semiconductors when measuring thermals along exposed pads on power devices. Link here (PDF) When measuring the rear of the package with a thermocouple, to measure accurately, the thermocouple must be in close contact with the package. A thermal pad for heat dissipation is exposed on the rear side and this thermal […]

App note: LED electrostatic breakdown

Very brief reminder from ROHM semiconductors about LED electrostatic destruction. Link here (PDF) LED products are classified as having a lower electrostatic breakage resistance than other semiconductor products. InGaN devices used in blue and white LEDs are more vulnerable to static electricity than other InGaAlP and GaP (red to yellow-green) devices.

App note: Impedance characteristics of bypass capacitor

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. […]

App note: BA1117 dropout voltage

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 […]

App note: Notes for temperature measurement using forward voltage of PN junction

App note from ROHM Semiconductors about the cautions when measuring temperature from PN Junctions. Link here (PDF) The forward voltage of a pn junction can be measured to estimate the junction temperature of a semiconductor device. However, correct results may not be obtained if the measurement is performed incorrectly.

App note: What is a digital transistor?

See the simple composition of a digital transistor, app note from ROHM Semiconductors. Link here A digital transistor is a bipolar transistor that integrates resistors. Bipolar operation tends to become unstable if the input (Base) is connected directly to the output terminal of an IC for voltage control. Inserting a resistor at the Base stabilizes […]

App note: Gate-source voltage behaviour in a bridge configuration

App note from ROHM semiconductor on MOSFETS and IGBTs. Link here (PDF) Power switching devices such as MOSFETs and IGBTs are used for various kinds of power supply applications, power supply line switching components, and other power applications. In addition, the circuit topologies used are diverse, parallel and series connections are widely used, not to […]

App note: Simple test method for estimating the stability of linear regulators

Tips from ROHM Semiconductor to estimate the stability of linear regulator using simple step response method. Link here (PDF) Low drop-out (LDO) regulators developed back in the age when large-capacitance multi-layer ceramic capacitors (hereinafter, MLCCs) were uncommon cause a phase delay, leading to oscillation when connected to a low-ESR capacitor like an MLCC. Often, MLCCs […]

App note: Linear regulator problem situations – Power supply does not start

App note from ROHM Semiconductor about various start up problem on 3 pins linear regulator. Link here (PDF) Although linear regulators can be used to easily configure power supplies, the linear regulators may cause startup problems depending on the type of loads. This application note introduces cases where the power supplies do not start correctly […]

App note: Linear regulator specifications

Thorough items on a linear regulator datasheet provides valuable details about its proper usage discussed in this App note from ROHM semiconductor. Link here (PDF) A linear regulator data sheet includes a specifications table that lists output voltage values and precision. Besides, very important information such as maximum ratings, operating conditions and characteristic graphs are […]

App note: Connecting LDOs in parallel

App note from ROHM semiconductor on combining LDOs for higher load capacity. Link here (PDF) When you want to increase the output current capacity of an LDO, or when the power dissipation of a single LDO is insufficient, you might think of connecting LDOs in parallel if you need to disperse the dissipation using two […]

App note: Linear regulators reverse voltage protection

Various input and output reverse voltage protection method for linear regulators discussed in this app note from ROHM. Link here (PDF) A linear regulator integrated circuit (IC) is a DC-to-DC buck converter system that reduces a DC supply from higher voltage level to a lower voltage level, thus it requires that the input voltage is […]

App note: Power source ON/OFF characteristics for linear regulator

A good read app note from ROHM on linear regulator On and Off characteristic. Link here (PDF) When a linear regulator IC is turned ON, the electric charge is stored in the output capacitor and the output voltage increases up to the specified value. At this time, an inrush current flows from the input to […]