A slightly more sophisticated power control device is the ltc2937 sequencer voltage supervisor from analog devices.
Power sequence controller ic.
Power sequencer tailored for unique systems.
The sample voltage applies externally can be derived from a simple 0 12v variable voltage power supply circuit.
This varying voltage applied to the 556 ic is used to vary the pwm of the pulses at the output and which eventually is used for the speed regulation of the connected motor.
Once the power rail is within 3 or less of its final value the reset ic enters the wait period defined by the solution before powering up the next rail.
Power sequencing is an essential part of any design especially in complex systems that utilize multiple power rails.
Take control of your power supply sequencing.
Ltpowerplay graphical user interface gui displays all of the status and debug register information in one convenient interface.
Today s high performance processing devices such as fpgas asics plds dsps adcs and microcontrollers require multiple voltage rails just to power their own internal circuitry such as the core memory.
Voltage monitors continuously check the power supply output voltages and currents for over and under threshold levels.
The ltc2937 can control the sequence of up to six supplies while also monitoring power rail voltages.
Configuring one or more ltc2937s is as simple as a few clicks of the mouse.
These applications typically require that the core and analog blocks be powered up before the digital i o rails although some designs may require other sequences.
If a fault is detected the supervisory ic automatically shuts down the system in an orderly fashion.
So can powering one off.
Using power sequencer can also prevent unnecessary current draw while portions of the design sit idle waiting for prerequisite systems to be powered.
This circuit was originally created to start up power supplies in sequence and subsequently switch them off for a second time in the opposite sequence.
This feature can be often useful for tinkering with equipment and circuits where power needs to be employed and taken out in a specific order.
With this option the reset ic monitors the power rails with tight threshold limits.
We can see that the power sequencing is accomplished by the interaction between the power logic the platform controller hub chipset and the imvp processor voltage regulator.
Power supply sequencers enable disable the power supplies in order at power up and power down.
Whether your system has two voltage rails or dozens we have a power sequencer to fit your requirements.
Successfully powering up a system can be tricky.
Like the lm3880 the ltc2937 can control the order and time delay of up to six power supplies or regulators figure 4.
Sequencing using a reset ic ing is a reset ic with time delay.