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Contents 1 SPECIFICATOINS 2 BONUS POINTS 3 PAYMENT SCHEDULE 4 DELIVERY SCHEDULE 5 DELIVERABLES

SPECIFICATOINS

Tentative specification for charge shuttling circuit to be designed by Lee Hart:

• ) The circuit will make it possible for any battery to either send power or receive power from a systemwide bus. Each individual battery will be isolated from this bus via caps rated for at least 500V. The circuit will be controlled by a microcontroller, which will use one input line (active either high or low) to enable sending power, and another to enable receiving power.
• ) Power should be sent between batteries via a single wire bus, as AC. Drive frequency is up to you, but it would be nice if there was some chance the FCC wouldn't lynch me the first time I used it. Also it would be nice if it didn't whine too loudly, although since I expect it to mostly be making noise when I'm nowhere near the car, that's not a hard requirement.
• ) The circuit will not fail explosively if the power transmission line is shorted to any part of the traction pack wiring or to 'frame ground'. It is acceptable for a fuse to open, but not for any other damage to occur.
• ) The circuit will not fail if every battery sends power and no battery receives power, or if every battery receives power and no battery sends power.
• ) The circuit will not fail if the controlling MCU selects both transmit and receive power at the same time. It's acceptable to simply make this impossible i.e. have one pin for enable and another pin for direction select.
• ) The circuit will not transmit or receive more power than would be healthy for itself i.e. even if one battery is dead empty and all the others are full and sending power, the circuit will limit current to that battery in such a way that nothing is damaged.

BONUS POINTS

I am offering a $100 bonus for each of these requirements that you meet

• The MCU can control the *amount* of power transmitted or received (via PWM)
• The MCU can measure the amount of power being transmitted or received
• The circuit has a parts cost that is less than $20
• The circuit has a parts cost that is less than $10 (yes, you get both the $20 and the $10 bonus if you meet this condition)

I am offering a $250 bonus if the circuit also permits transmitting and receiving data at 9600 baud or higher. The ability to transmit and receive data is more important to me than a low parts cost.

PAYMENT SCHEDULE

I will pay $1000 per month, starting on May 1st. I will not pay the final $1000 or the bonuses until I have the deliverables.

Payment will total $5000 plus any bonus points that you manage to garner

DELIVERY SCHEDULE

Tentatively the deliverables would be due by Jan 1, 2009.

DELIVERABLES

The following should be considered parts of the deliverable final product:

• ) A circuit diagram complete with part values and sources for all 'unusual' parts i.e. inductors, weird capaciters, non-standard ICs. Note that the source for the inductors should be for *completed inductors*, not cores and 'wind them yourself'. I'm willing to buy them from you - and I'm willing for you to make a profit - but I want to be able to get them from somewhere in qty 100.
• ) Circuit notes describing the theory of operation, how to interface with the circuit, and any hints and tips for debugging problems with it
• ) *NON-EXCLUSIVE* use of the circuit in any products I design. (Meaning, you can sell it to other people, I don't care, you can patent it as long as you agree to let me continue to use it). If someone else holds the patent and they come after me, I agree that that's not your problem.
• ) 2 rounds of review of the PCB layout of the circuit
• ) Three breadboarded working prototypes