

Layout Changes
- Move all of the following to the upper left side of the board, and 
    lay out like on page AN85-2 of app note
      - C284-C287, C296-C298
      - U205
      - L203, L204
      - D201, D202
      - R204, R205
- Move C282 to top side, right near U209 pin 16
- If possible, move C280 and C281 to top, near U209 pins 7 and 15
- Put direct traces between top layer decoupling caps and power pins
    of U103
- Put C130-C135 on top layer (this avoids vias in filter)
- Add a little space between L102 and L107.  Same for L105 and L109.
    This gives better IQ isolation.
- R21X labels are on vias (on back)
- C106 and C107 should have direct traces to L113 and L114 on top layer
- Need real 50 ohm balanced, protected traces on nets clock_rx_p and clock_rx_n
- LNA layout (around U4) --
      - C205 and L99 need to be in a straight line
      - R68, L98, C97, C98 need to be close to U4, connected on top layer,
         should look like schematic
- C93 should be close to its pin, don't run long line in parallel 
- Open up space on left of U2 -- too much coupling

- Moved bias resistors from U210 (divider) to top layer


Part Value Changes, same footprint
- C284, C286 (4.7uF ceramic) are now X5R, and are 35V or 50V rated
- R204 is now 9.53K, 1% metal film
- L203 is a 1206 Ferrite Bead
- R95 is now 1K
- R206 is now 49.9 ohms
- Removed J201
- R213 is now 49.9 Ohms

Footprint Changes, same part
- C47, C126, C208, C228 changed from 1206 to 1206P to get polarity indicator


Part Changes, different footprint
- C284 changed from 0603 to 1206, same part as C286
- L204 is still 10uH, but is now part number MP2-100-R, with a
     footprint of MP2
- U101 is a different part now
- C123 and C126 are different

Schematic changes, added parts
- Added C296, C297, C298 to switcher
- Added C42, place it right next to U7
- Added C270, R252, R253, place them near U208
- Added C254, should be placed right at U207 pin 14
- Added ATN1, ATN101, ATN102
- Added U105, L120, C170-C172 power amp
- Added R155, should be placed close to U103
- Added R218, C273, should be near switcher
- Added RSSI circuit -- U3, C20-C26, R70, R71.  All but R's should be
    close to each other
- Added R72, R73, C56, should be near U2
- Added R245-258, T200, T101
Schematic changes, removed parts
- Removed R2, R3, R12, R114, R115, R129, R130, R131, R155 (attenuators)
- Removed C292, C293, T200, R212, R213, J203

Connectivity changes
- U207 now on 5V_COM (was on 5V_RX)
- Switcher now on 6V_TX (was on 5V_COM)
- Got rid of 3_3V_SW, now on 3_3V_COM net
- T2, T100 had connections reassigned for better flow
- io_tx_01, io_tx_02, io_tx_03 instead of just io_tx_01
- Removed DGND, everything is on AGND
- Swapped RX diff pairs

Open Issues
- Values of 3 attenuators, close to source or dest?
- Loop filter
- Examine all RF paths


Not Doing
- Tranformer in LNA path
- 64 Mhz filtering? differential to SE xformer?
