Digital design engineer Interview Questions
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Digital Design Engineer interview questions shared by candidates
Create a 8 input AND gate using 3 4:1 muxes
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Without an enable bit on at least one of the mux's the maximum inputs would be 7. Less
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I don't see it being possible with three standard 4-1 muxes... Using 4, this question is straight forward... The two selects of each mux are your 8 inputs... tie out put of each mux to the (11) case input to the mux. Less
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We need 3 4:1 MUX and a And gate. Are we allowed to use 'and' gate?
Cross clock domain synchronizer, 1 bit.
2 Answers↳
Add one flip-flop on the output of destination register.
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There's quite an extended back and forth in actual interviews for questions like this, so nothing quite like real practice. The Prepfully Qualcomm Digital Design Engineer experts have actually worked in this role, so they're able to do an honest-to-God accurate mock, which really puts you through the paces. prepfully.com/practice-interviews Less
Verilog question with additional requirements. Design a FSM providing fibonacci sequence with enable and reset. Output should be immediate.
2 Answers↳
Two registers storing last two numbers in sequence with adding circuit muxed with the enable signal. Combinational output from mux. Answer should be in verilog code. Less
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This is actually another way of asking: what is the difference of blocking and non blocking assignment. and the key point in this question is to use the non blocking assignment Less
So tell me about you? Why do you want to work at Netlist?
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You got no offer because they prefer to hire their buddy. and only few y of thejob ads actually a real hiring Less
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You are lucky you did not pass the interview. It is a terrible hostile working environment if you are not a part of the persian or korean gang. Also, the HR lady has been monitoring this glassdoor like a hawk, because she got not much to do everyday than watching people to make sure they do 8-hour a day like walmart employees. Less
metastability in design
2 Answers↳
when the flops goes in to an unknown state ( either 1 or 0)
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The key in these questions is to cover the fundamentals, and be ready for the back-and-forth with the interviewer. Might be worth doing a mock interview with one of the Texas Instruments or ex-Texas Instruments Digital Design Engineer experts on Prepfully? They give real-world practice and guidance, which is pretty helpful. prepfully.com/practice-interviews Less
What is setup hold time
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Setup time is the time the data should be held constant before the arrival of the clock edge. Less
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Set Up time is Minimum Amount of time During which Data Signal Should be Stable Before the Clock made a Valid[Low-to-High] Transition. Hold time is the Minimum Amount of time After the Clock Made a Valid Transition During which Data Signal Should Stable. Less
Given integers from 0-100 stored in an array of size 100 how will you find the missing number? Numbers are randomly entered in the array.
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0-100 have constant addition. add the numbers in the array and subtract it from the constant sum. Less
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Assuming that a number only appears once, find the sum and subtract from the total possible value (1+2+3+....+100) and subtract to find the missing number. But it would be smart to ask if a number can appear multiple times or not since that may increase or decrease the complexity of the problem, but shows that you're really thinking about all the problem parameters. Less
What is MOESI?
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MOESI is a cache coherency protocol- like the MESI (Modified, Exclusive, Shared and Invalid) but with an "Owned" state. Modified: Data is recent (and has been modified!) and this data is held by no other processor or the memory. This data is 'dirty'. Exclusive: Data is recent and present only in the current cache and the memory holds a copy as well. No other processor holds this data. Shared: Other caches may also have this data and the data matches memory. This data is 'clean'. Invalid: The data is invalid or incorrect. Owned: The Owned state signifies that the data is Modified as well as Shared. While the data must be still written to memory, this can be delayed since there is no need to write the modified data into memory before sharing it. Less
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This is ofcourse, for a Write-back Cache!