l16_print

# l16_print - L16: Power Dissipation in Digital Systems L16:...

This preview shows pages 1–7. Sign up to view the full content.

L16: 6.111 Spring 2004 1 Introductory Digital Systems Laboratory L16: Power Dissipation in Digital Systems L16: Power Dissipation in Digital Systems

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
L16: 6.111 Spring 2004 3 Introductory Digital Systems Laboratory Problem #2: Energy Consumption Problem #2: Energy Consumption (from Jon Eager, Gates Inc. , S. Watanabe, Sony Inc.) No Moore’s law for batteries… Today: Understand where power goes and ways to manage it
L16: 6.111 Spring 2004 4 Introductory Digital Systems Laboratory Dynamic Energy Dissipation Dynamic Energy Dissipation V DD C L E 0 1 = C L V DD 2 E cap = 1/2C L V DD 2 i DD E diss, RP = 1/2C L V DD 2 V DD C L IN =1 E diss,RN =1/2C L V DD 2 Charging Discharging IN =0 P = C L V DD 2 f clk R N R P R N R P

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
L16: 6.111 Spring 2004 5 Introductory Digital Systems Laboratory Transition Activity Factor Transition Activity Factor α α 0 −> 1 Current Input Next Input Output Transition 00 00 1 −> 1 00 01 1 −> 1 00 10 1 −> 1 00 11 1 −> 0 01 00 1 −> 1 01 01 1 −> 1 01 10 1 −> 1 01 11 1 −> 0 10 00 1 −> 1 10 01 1 −> 1 10 10 1 −> 1 10 11 1 −> 0 11 00 0 −> 1 11 01 0 −> 1 11 10 0 −> 1 11 11 0 −> 0 Z A B Assume inputs (A,B) arrive at f and are uniformly distributed What is the average power dissipation? α 0 −> 1 = 3/16 P = α 0−>1 C L V DD 2 f
L16: 6.111 Spring 2004 6 Introductory Digital Systems Laboratory Junction (Silicon) Temperature Junction (Silicon) Temperature Simple Scenario Realistic Scenario T j -T a =R θ JA P D Silicon Sink Case Silicon T J T C T S T A T J R θ JA is the thermal resistance between silicon and Ambient R θ JC P D T J R θ JA T C R θ CS P D T S T j =T a + R θ JA P D T A R θ SA T A R θ CA = R θ CS +R θ SA Make this as low as possible is minimized by facilitating heat transfer (bolt case to extended metal surface – heat sink)

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
L16: 6.111 Spring 2004 8 Introductory Digital Systems Laboratory Intel Pentium 4 Thermal Guidelines Intel Pentium 4 Thermal Guidelines ± Pentium 4 @ 3.06 GHz dissipates 81.8W!
This is the end of the preview. Sign up to access the rest of the document.

## This note was uploaded on 07/21/2009 for the course EECS 6.111 taught by Professor Prof.ananthachandrakasan during the Spring '04 term at MIT.

### Page1 / 23

l16_print - L16: Power Dissipation in Digital Systems L16:...

This preview shows document pages 1 - 7. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online