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Hello everyone, in this lesson we will look at the generation circuit of VPP
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First of all, we open the drawing and look for VPP in the drawing
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You can see that there is no VPP in the directory
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We directly searched for VPP and found the generation circuit of VPP
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This circuit is very simple, it's just an LDO circuit
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There are two power supplies and a turn-on signal, it will work, it will generate a VPP of 1.8V,
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and generate a POWERGOOD signal at the same time
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So let's see where its power comes from
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First of all, its VDD power supply comes from 5V or 3.3V gold finger
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This is a design with multiple options, choose one of the two
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5V or 3.3V gold finger power supply has been generated in the previous circuit
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Let's draw the power supply first
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After the power supply is satisfied, let's look at the open signal
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Its turn-on signal should be a high level
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The external name of the enable signal is VPP_EN
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Let's find this turn on signal
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It can be seen that the PG signal of 0.75V is transferred directly through the 0 ohm resistor.
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The PG signal of 0.75V has been generated in the previous circuit
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So VPP_EN already has
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With the power supply and open signal, the chip can work and generate VPP power supply.
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And it also generates a PG signal
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So far, the VPP power supply has been generated normally.
