Questions tagged [power-up-conditions]

9 questions
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How can I float a pin that otherwise should be low?

I want to enable/disable a TI TPS54302 buck regulator with a microcontroller. The enable (EN) pin should float to enable the device, or be tied low to disable it. I currently have the EN pin connected to a GPIO pin on the MCU. At startup, before the…
JYelton
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Problem turning on low power (TPS709) to MPPT (ATtiny85) after dawn

I have a relatively low-power autonomous device, which will be left untouched for weeks or months. Solar recharging is therefore very important. Maximising solar power for overcast days is also important - every milliamp counts. The Maximum Power…
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LTspice .TRAN UIC simulations with initial conditions as .IC directives

Starting from this question a doubt arises about the use of (global) .IC directives for 'branch currents' in LTspice (or maybe just SPICE) Consider the .TRAN card with UIC flag. From some test done it seems to me possibly .IC directives set for…
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LTSpice transient simulation of LC circuit

I've a question about the LTSpice simulation of the following simple LC circuit driven by a DC current source. The first simulation (A) looks good from point of view of initial conditions for either voltage cap V(n001)=0 and inductor current…
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MCP16301 fail on power up - Vin shorted to Vout

I have designed a step-down converter PCB (4-layer) with MCP16301. It converts voltage from 24V to 5V. When I connect it to power source and then connect a 100ohm resistor (50mA@5V) it works normally. But when the load is applied before I power it…
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How to power up a display before the controlling MCU?

To write a driver for a display I set up up the following circuit: simulate this circuit – Schematic created using CircuitLab Whilst developing the display driver I would regularly plug in the USB port to both upload programs and run the programs…
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Do any FPGAs that set undefined values ​in registers after power up exist?

There is some discussions how to set default values or start an initial sequence in FPGAs design after programming/power-up. The most reliable method is using a supervisor IC which guaranteed send the reset signal. But this method needs a descrete…
Arseniy
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powerup and power down delay circuit

I have a customer requirement to enable and disable enable pin of regulator using GPIO. We a delay circuit in between. Delay is required both for powerup and power down condition. Can someone suggest me a circuit for powerup and power down delays…
Shifali
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Microcontroller goes endless loop while power up

I am using atmega328pb controller and Arduino Framework with mini-core. The problem is that the microcontroller goes into a never-ending loop while power up. I found this while debugging. Actually, I am using while(1) loops in the program, and…
Dinesh
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