ESTIMATING POWER DISSIPATION IN CMOS DEVICES APPLICATION NOTE
●INTRODUCTION:
■Due to higher system frequencies, new packages and programs like the “Energy Star” initiative, a strict limit on computer system power budgets is common these days. Allowable power dissipation for each device on a board needs to be minimal. CMOS devices have negligible static power dissipation, but when switching at a high frequency, dynamic power dissipation can significantly contribute to overall power dissipation. Capacitive output loading further increases this dynamic power loss.
■This application note describes ways to estimate power dissipation of individual CMOS logic devices in a system. It will help users determine if their designs raise any power dissipa-tion concerns. The equations used here are applicable to simple bus interface devices where the dominant power dissipation is in the output drivers rather than internal to the device. In more complex devices such as a large ASIC or processor where internal nodes may switch at higher frequen-cies and contribute significantly to overall power, other factors enter into the equations. In such cases the simplification used here may not yield accurate results. Please refer to individual datasheets or application notes in such cases. Examples are given using IDT FCT/FCT-T Logic devices. Power dissipation in a clock driver is of particular concern, because this kind of device has all outputs continuously switching. Charts relating thermal limits to maximum allowable power, frequency and load are also given for IDT FCT, FCT-T and clock devices.
|
805 、 806 、 805T 、 806T 、 807T 、 810T 、 3805 、 3807 、 88915TT 、 388915T 、 3932 、 FCTxxx 、 FCTxxxT 、 FCT2xxxT 、 FCT3xxx 、 FCT16xxxT 、 FCT162xxxT 、 FCT166xxxT 、 FCT163xxx 、 FCT374 、 FCT16823 、 FCT805 、 FCT806 、 FCT805T 、 FCT806T 、 FCT810T 、 FCT807T 、 FCT3805 、 FCT88915TT 、 FCT388915 、 FCT3932 、 FCT3807 |
|
|
|
|
|
Application note & Design Guide |
|
|
|
|
Please see the document for details |
|
|
|
|
|
|
|
|
PDIP-20;SOIC-20;SSOP-20;QSOP-20;CERDIP-24;LCC-24;CERPACK-24;PLCC-28;SSOP-28;SSOP-48;TSSOP-48;PDIP-16;PDIP-24;SOIC-16;SOIC-24;SOIC-28;SSOP-16;SSOP-24;QSOP-16;QSOP-24;CERDIP-20;SSOP-56;TSSOP-56;CERPACK-48;CERPACK-56 |
|
|
English Chinese Chinese and English Japanese |
|
|
2020/02/07 |
|
|
|
|
|
AN-154 |
|
|
318 KB |
- +1 Like
- Add to Favorites
Recommend
All reproduced articles on this site are for the purpose of conveying more information and clearly indicate the source. If media or individuals who do not want to be reproduced can contact us, which will be deleted.
Integrated Circuits
Discrete Components
Connectors & Structural Components
Assembly UnitModules & Accessories
Power Supplies & Power Modules
Electronic Materials
Instrumentation & Test Kit
Electrical Tools & Materials
Mechatronics
Processing & Customization
