Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

UPF: What is isolation sense in isolation strategy?

Status
Not open for further replies.

swabhi812

Member level 2
Member level 2
Joined
May 18, 2018
Messages
45
Helped
4
Reputation
8
Reaction score
4
Trophy points
8
Activity points
349
Hey experts,

While reviewing UPF and isolation strategies, I have few questions. I will appreciate if you can resolve them.
While defining isolation strategy, we do have following UPF commands. These are copied over from UPF LRM.

set_isolation <isolation strategy name> \
-domain <domain name> \
-isolation_power_net <VDD> \
-isolation_ground_net <VSS> \
-clamp_value 1 \
-elements { .. }

set_isolation_control <isolation strategy name> \
-domain <domain name> \
-location <self/parent> \
-isolation_signal <isolation signal> \
-isolation_sense <low/high>
Questions:
1. What is isolation signal here? How is this different than clamp value?
2. What is isolation sense. This is what I found from LRM:
-isolation_sense — Specifies the isolation sense of the signal. By default, the isolation sense is high, which means that the logic value is isolated when the signal value is high.

I am looking for details here.

Thanks,
Abhishek
 
Last edited by a moderator:

The isolation signal is the signal used to control when isolation is enabled. The sense of that signal, specifies whether the isolation is enabled when that signal is high or low.
 

Thanks for your response. Few clarifying questions:

1. Does clamp value only tell the tool to choose which kind of gate to use?
2. Let's say clamp value is 0, hence, I believe AND gate will be used as isolation cell. I guess when isolation signal is inactive (should be 1 in this case), this AND gate will act as a buffer, but when it is active (should be 0, same as clamp value), output of isolation cell will be 0. Is this correct?
3. How does isolation sense fits here? If #2 is correct, based on clamp value only we can decide if isolation signal can be high or low.

PS: I was not able to find a detailed circuit of an isolation cell, hence, I have these questions.

Thanks,
Abhishek
 

Thanks for your response. Few clarifying questions:

1. Does clamp value only tell the tool to choose which kind of gate to use?
2. Let's say clamp value is 0, hence, I believe AND gate will be used as isolation cell. I guess when isolation signal is inactive (should be 1 in this case), this AND gate will act as a buffer, but when it is active (should be 0, same as clamp value), output of isolation cell will be 0. Is this correct?
3. How does isolation sense fits here? If #2 is correct, based on clamp value only we can decide if isolation signal can be high or low.

PS: I was not able to find a detailed circuit of an isolation cell, hence, I have these questions.

Thanks,
Abhishek

1. correct
2. correct
3. the sense tells you when the isolation should be enabled, whether the value should be isolated when the isolation signal is high or when it is low
 
Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top