Implementing Low Power Mode in Set Top Boxes

STB International Stakeholder Meeting

San Francisco, California

Suzanne Foster

Ecos Consulting

970.259.6801 x 302

sfoster@ecosconsulting.com

Possible Design Changes to Make Low Power Mode Possible

• Hardware enabling shut down of non critical systems– Hardware build so that circuits not in use can be powered

down and then “wake” easily and quickly when needed for service

– Analogous to “sleep” technology developed by Intel and others in PC world, sold in virtually all PCs on shelves today

– Memory solutions already found in desktops could store program guide, etc. when in low power mode

• Hardware reducing power use, regardless of mode – “Power partitioning” chips – Power supply

Base system: 1024 MB DDRI, nVIDIA GeFORCE 4 MX 440 video card, 80 GB HD, DVD/CD-RW, stock power supply

0 20 40 60 80 100 120

Athlon 64 3000+

Athlon 64 3500+

Athlon 64 3800+

Athlon 64 4000+

Athlon FX-53

Athlon FX-55

System Idle State Power (AC watts)

Base system

+ Cool 'n Quiet

Power Partitioning Chips Save Energy in Desktops

Power Supply Possible Near Term Solution

Efficiencies between 68% and 82% measured, 85% efficiency achievable today

Possible Design Changes to Make Low Power Mode Possible (cont.)

• Software changes to accommodate low power mode– “Energy Saver” DVR options that allow hard drives to

spin down if customer chooses not to record material

• Communication protocols – enable proper security and downloads of content to

customer from head end– communication among multiple STBs in one home

Goal: Energy Savings in Customer’s Homes

• Possible for low power mode to be technically achievable and measurable in the lab, but not implemented in the field

• Reasons for this could include:– Needs of the service provider not fully taken into account when

designing system, so low power mode is disabled in field– Customer dissatisfaction with solution

• Lack of transparency to user• Customer misunderstands important environmental impact and

associated energy bill savings

– Poor communication protocols between head end and box and among boxes

Test Method Implications

• IEC 62087 currently measures static power values for defined modes

• Alternate approach: measurement of STB energy over 24 hour period with standard duty cycle, allowing box to fall into low power as it would in the home

• Other considerations:– Easy to conduct– Reproducible– Robust– Representative

Discussion