TheCircuitDogPower Sequencing and PGOOD Logic
When one supply enables another through PGOOD, the important signals are the actual voltage waveforms—not the appearance of a status LED.
Read guide →Hardware lab
Engineering Guides
Nonproprietary, educational workflows for understanding, checking and troubleshooting real circuits.
Choosing Power-Good Pull-Ups
A pull-up resistor on a PGOOD output is not just a formality: it determines rise time and the current the driving transistor must sink.
Read guide →LDO and DC-DC Regulator Startup Troubleshooting
A regulator that occasionally needs a manual jump-start may be experiencing an enable threshold issue, input collapse, output overload, thermal shutdown or an unintended back-power path.
Read guide →How Backfeeding Happens Through I/O and ESD Structures
One powered rail can energize a supposedly unpowered rail through signal-pin protection structures, pull-ups or output drivers.
Read guide →Decoupling Capacitors: Placement and Selection
Decoupling is an electrical loop problem as much as a capacitance problem. A small capacitor very close to a supply pin can be more effective at high frequency than a larger one farther away.
Read guide →PCB Grounding and Return Paths
A return path completes every signal-current loop. Most PCB “grounding problems” are really unwanted current loops or disrupted return paths.
Read guide →Oscilloscope Probing for Power Rail Bring-Up
A correct circuit can look broken when the probing technique is wrong. Good measurements use a safe connection, sufficient bandwidth and a trigger that captures startup.
Read guide →New PCB Bring-Up Checklist
A consistent pre-power checklist makes first-article board bring-up safer and quicker to repeat.
Read guide →PCB Trace Width vs Resistance and Heating
A PCB trace’s DC resistance is straightforward to calculate, but its allowable current depends on the board stackup, thermal environment and layout.
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