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Who can help me with these parameters?

I am reading a document of chip MAX900. There are some parameters I do
not know. Please you help me with these para..
1.input-to-output high response time
2.difference in response time between outputs
3.latch disable to output high delay
4.latch disable to output low delay
5.minimum setup time
6.minimum hold time
7.minimum latch disable pulse width
8.input overdrive
 
I am reading a document of chip MAX900. There are some parameters I do
not know. Please you help me with these para..
1.input-to-output high response time
overdrive the input by 5mV and the output will go high within 15ns
2.difference in response time between outputs
overdrive multiple comparators at the same time and they will flip
within 3ns of each other
3.latch disable to output high delay
OK, now you actually asked a question that takes some thought, mostly
because the datasheet is poorly written. It looks like the latch is
active low. When you disable the latch, you move the pin from low to
high. The comparator output (internal signal) can now propagate. The
propagation typically takes 10ns.
4.latch disable to output low delay
as above
5.minimum setup time
This refers to the latch. The input (really the internal comparator
signal) needs to be steady for typically 2ns.
6.minimum hold time
The internal comparator signal needs to be steady for typically 1ns
for the proper value to be latched
7.minimum latch disable pulse width
When the latch pin is high, the output reflects the internal
comparator signal. The pin must be high typically 10ns. I don't quite
follow this unless they are doing some power savings when the signal
is latched.
8.input overdrive
Overdrive is the voltage above the built-in offset of the comparator.
Overdrive is a test condition rather than a parameter of the chip.

A good thing this chip is history, The datasheet is crap.
 
F

Fred Bloggs

A good thing this chip is history, The datasheet is crap.

Readily comprehendible to anyone with experience using high speed
comparators...
 
L

lyra

On Mar 16, 12:28 am, [email protected] wrote:> I am reading a documentof chip MAX900. There are some parameters I do

overdrive the input by 5mV and the output will go high within 15ns


overdrive multiple comparators at the same time and they will flip
within 3ns of each other


OK, now you actually asked a question that takes some thought, mostly
because the datasheet is poorly written. It looks like the latch is
active low. When you disable the latch, you move the pin from low to
high. The comparator output (internal signal) can now propagate. The
propagation typically takes 10ns.


as above


This refers to the latch. The input (really the internal comparator
signal) needs to be steady for typically 2ns.


The internal comparator signal needs to be steady for typically 1ns
for the proper value to be latched


When the latch pin is high, the output reflects the internal
comparator signal. The pin must be high typically 10ns. I don't quite
follow this unless they are doing some power savings when the signal
is latched.


Overdrive is the voltage above the built-in offset of the comparator.
Overdrive is a test condition rather than a parameter of the chip.
I am not quite sure about "Overdrive ". What does "built-in offset"
mean? Please continue to help me.
 
On 3月16æ—¥, 下åˆ4æ—¶11分, [email protected] wrote:














I am not quite sure about "Overdrive ". What does "built-in offset"
mean? Please continue to help me.

The comparator will have some offset error, i.e. it is not perfect.
Generally the offset is small, so in practice you would apply 5mV in
either direction to the differential input to test the device.
Technically, this should be 5mV beyond the offset.

Comparator speed is related to the overdrive. If you only had a
microvolt of overdrive, the comparator would take a long time to
flip.

A good datasheet explains all the test conditions, including timing
diagrams. This is an example of a poorly written datasheet. I'm sure
it generated a few calls to Maxim apps.
 
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