Spartan-3 VCCINT

[Kolja Sulimma]

This again is a question for Austin:

The recommended operating conditions for spartan-3 are VCCINT < 1.26V.
What will happen if I power it with 1.28V?

Antything more serious than a live expectancy reduced from 20 years to
15 years?

You know, there a only a few small 1.2V regulators on the market but
there a plenty of 1.25V versions around. But those have a tolerance of
a few percent...

Kolja Sulimma

 

[fabbl]

According to the data sheet, the absolute maximum VCCINT is 1.32 volts. This
would be 4% high side tolerence for a 1.25 V regulator. I am not aware of
any derating Xilinx has for higher voltages with their Spartan 3 device. I
would conclude a 1.25 V regulator would be acceptable. If you were really
paranoid you could tweak down the regulator by adjusting the passives in the
circuit.

"Kolja Sulimma" <news@sulimma.de> wrote in message
news:b890a7a.0401160555.6965219c@posting.google.com...

This again is a question for Austin:

The recommended operating conditions for spartan-3 are VCCINT < 1.26V.
What will happen if I power it with 1.28V?

Antything more serious than a live expectancy reduced from 20 years to
15 years?

You know, there a only a few small 1.2V regulators on the market but
there a plenty of 1.25V versions around. But those have a tolerance of
a few percent...

Kolja Sulimma

 

[Austin Lesea]

All,

The voltage drop to the part might be just about 50mV....

Seriously.

I would try it an see what voltage the part actually is at relative to
the regulator. You might be pleasantly surprised.

Remember the part is specified by Xilinx to operate at the abs max
voltage AND temperature for the rated lifetime.

We prefer you stay within the recommended values, however.

Austin

fabbl wrote:

According to the data sheet, the absolute maximum VCCINT is 1.32 volts. This
would be 4% high side tolerence for a 1.25 V regulator. I am not aware of
any derating Xilinx has for higher voltages with their Spartan 3 device. I
would conclude a 1.25 V regulator would be acceptable. If you were really
paranoid you could tweak down the regulator by adjusting the passives in the
circuit.

"Kolja Sulimma" <news@sulimma.de> wrote in message
news:b890a7a.0401160555.6965219c@posting.google.com...

This again is a question for Austin:

The recommended operating conditions for spartan-3 are VCCINT < 1.26V.
What will happen if I power it with 1.28V?

Antything more serious than a live expectancy reduced from 20 years to
15 years?

You know, there a only a few small 1.2V regulators on the market but
there a plenty of 1.25V versions around. But those have a tolerance of
a few percent...

Kolja Sulimma

 

[Kolja Sulimma]

OK.
As I am probably inside the recommended spec and for granted in the the
abs max spec I stop worrying.

Thank you Austin,

Kolja Sulimma

Austin Lesea <austin@xilinx.com> wrote in message news:<bu92l9$jjb2@cliff.xsj.xilinx.com>...

All,

The voltage drop to the part might be just about 50mV....

Seriously.

I would try it an see what voltage the part actually is at relative to
the regulator. You might be pleasantly surprised.

Remember the part is specified by Xilinx to operate at the abs max
voltage AND temperature for the rated lifetime.

We prefer you stay within the recommended values, however.

Austin

fabbl wrote:
According to the data sheet, the absolute maximum VCCINT is 1.32 volts. This
would be 4% high side tolerence for a 1.25 V regulator. I am not aware of
any derating Xilinx has for higher voltages with their Spartan 3 device. I
would conclude a 1.25 V regulator would be acceptable. If you were really
paranoid you could tweak down the regulator by adjusting the passives in the
circuit.

"Kolja Sulimma" <news@sulimma.de> wrote in message
news:b890a7a.0401160555.6965219c@posting.google.com...

This again is a question for Austin:

The recommended operating conditions for spartan-3 are VCCINT < 1.26V.
What will happen if I power it with 1.28V?

Antything more serious than a live expectancy reduced from 20 years to
15 years?

You know, there a only a few small 1.2V regulators on the market but
there a plenty of 1.25V versions around. But those have a tolerance of
a few percent...

Kolja Sulimma