豪威(Omnivision)笔试题目

Omnivision examiner use only
2005 china career fair exam
1 logic design
e is a fifo design which the clock of data input is running at100mhz,while the clock of data output is running at inputdata is a fix pattern .800 input clocks carry in 800 datacontinuously,and the other 200 clocks carry in no big the fifoshould be in order to avoid data over/under_run?please select theminimum depth below to meet the requirement.
A.160 b.200 c.800 d .1000
osedly there is acombinational circuit between two registersdriven by a will you do if the delay of the combinationalcircuit is greater than the clock signal?
reduce clock frequency increase clock frequency
make it pipelining d to make it multi_cycle
h of the follow circuits can generate gitch free gated_clk?
ys@(posedge clk) gated <=en;assign gated_clk=gated&~clk;
ys@(negedge clk) gated <=en;assign gated_clk=gated&~clk;
ys@(posedge clk) gated <=en;assign gated_clk=gated|~clk;
ys@(negedge clk) gated <=en;assign gated_clk=gated|~clk;
’re working on a specification of a system with some parameter has min,typ and max h columnwould you put setup and hold time?
p time in max,hold time in min
p time in min,hold time in max
in max
in min
e are 3 ants at 3corners of a triangle. They randomly startmoving towards another is the probability that won’tcollide?
a.0
b.1/8
c/1/4
d.1/3
you look at a clock and the time is 3: is angle between the hour and the minute hand?
a.0
b.360/48
3.360/12
d.360/4
many times per day a clock’s hands overlap?
a.11
b.22
c.24
d.26
8.d flip-flop :t_setup=3 ns; t_hold =1 ns; t_ck2q= is the max clock frequency the circuit can handle?
A.200mhz
b.250mhz
c.500mhz
d.1ghz
ical design
re tape-out,which routine check should be performed for your layout database in 0.18 um process?


&antenna
lation
to fix antenna effect?
the wire wider and shorter
ge lower metal to upper metal
ect with diode of metal and diffusion
ge upper metal to lower metal
e.b&c
se expain lvs
c versus schematic
ut versus schematic
ut via synthesis
c via synthesis
to control clock skew?
balanced clock tree
ease the fanout
clock buffer evenly
ease clock latency
to avoid hold_time violation?
r the clock speed
clock arrive later
clock arrive earlier
data arrive later
data arrive earlier
kinds of factors reflect good floor plan?
routing
timing met
gh power supply
d.a&b
e.a&b&c
cause cell delay?
t-pin transition time
ut-pin capacitance.
ut-pin resistance
d.a&b
e.b&c
need i/o pads for each chip?
protection
age level shift
h-up prevention
d.a&c
e.a&b&c
h one is worse-case in 0.18um process?
1.1.8v,25c
2.1.98v,125c
3.1.62v,-40c
4.1.62v,125c
5.1.98v,-40c
power plan is not good,what’ll happen to the chip?
a.hot-spot
age drop
ng not met
ing is tough
of above
itecture design
are two images,the first image has a person in front of ablackboard in a classroom and the second image has a person in front ofa lush two images are compressed using the jpeg algorithm.
first image will have larger file size.
second image will have a larger file size.
would you round a 10b number,x,at the 3rd(上角)bit?
a.(x>>2)<<2.
b.(x>>3)<<3.
c.((x+4)>>2)<<2
d.((x+4)>>2)<<3
e.((x+8)>>2)<<3
f.((x+8)>>3)<<3
happens if the number in 2 is negative?
A ignore
it absolute ,do the operation in 2,and add sign back
of the above
would you multiply a 4 in hardware?
4 adders each is offset from the provious adder by 1bit.
a booth multip;ier with 4b coefficient.
wires.
a barrel shifter.
is a fifo?what is a filo?which one is a queue? Which one is a stack?
is a queue and filo is a stack.
is the name of a dog. Filo is the name of a cat.
is a stack and filo is a queue.
would you design a barrel shifter?
multiple stages of 2乘2 multiplexers
a crossbar switch that can switch any inputs to any outputs
a clos network
muxes to switch between all combinations of hardwired shifts.
还有chip verification、algorithm design、hardware design、analog design。