X-Git-Url: https://git.gag.com/?a=blobdiff_plain;f=Notebook;h=07b22c7da567101c05f0b9fba2efaa5a9963b0c9;hb=abd96bd2d55c3514ca9d0d138089bbdc2f8461b1;hp=3542ca466275d10827d419fcf0032ee0a1c6a6af;hpb=e652075a95873157fdb702aa3bf396eb31d79a97;p=hw%2Ftelemetrum

diff --git a/Notebook b/Notebook
index 3542ca4..07b22c7 100644
--- a/Notebook
+++ b/Notebook
@@ -153,3 +153,70 @@
 	AT45DB161D-SU-ND in SOIC-8 for $2.26 each
   appears to compare favorably against $4.40 for current 128kx8 part
   minor concern about write power, but probably red herring
+
+2010.02.08
+- looking at LiPo charger alternatives
+
+	MAX8808		DFN8, not carried by DK
+	MAX8814		DFN8, not carried by DK
+
+	LTC4095		DFN8, LTC4095EDC#TRMPBFCT-ND 2.91 2.34@100
+		950mA, resistor current set, rate limit input, suspend input,
+		NTC thermal control option, smart CHRG led with 4 states
+	LTC4065		DFN6, LTC4065EDC#TRMPBFCT-ND 2.77 2.23@100
+		750mA, resistor current set, CHRG led, enable input
+	LTC4065A	DFN6, LTC4065AEDC#TRMPBFCT-ND 2.77 2.23@100
+		750mA, resistor current set, CHRG led, supply present out
+		
+	MCP73811	SOT23-5, MCP73811T-420I/OTCT-ND 0.63@1 0.39@100
+		input selects 85 vs 450mA charge current
+
+	MCP73837	DFN10, MCP73837T-FCI/MFCT-ND 1.37@1 0.85@100
+		usb rate select, power good output, dual inputs, dual status
+
+	LX2206		DFN10, LX2206CT-ND 2.68@1 2.01@100
+		rate select, power good output... needs more passives?
+
+	LM3658		DFN10, 
+		dual input, dual rate, two status outputs .. not obvious win
+
+	MCP73855	DFN10, MCP73855T-I/MFCT-ND 1.85@1 1.18@100
+		see Microchip app note 971
+
+
+  Talking to Keith, there's no reason we couldn't use an 8-pin PIC to augment
+  a standalone LiPo charger, implementing a timer after vusb application 
+  before switching the regulator to high current, to allow the cc1111 time to
+  finish the USB bus negotiation phase.  We could also monitor various state
+  bits and multiplex signaling onto one LED.  A combo like the MCP73837 plus
+  a PIC10F206 or 220 would net under $1.50 at 100 pieces and be pretty 
+  powerful.  Since the PIC has avilable weak pull-ups on the gpio lines, the
+  open-drain state outputs from the regulator don't need resistors to be read.
+
+2011.01.17
+- v1.0 and v1.1 boards have a minor error in that the v_lipo sampling resistors
+  are on "the wrong side of the cut" if you try to use a separate pyro battery.
+  The workaround is to cut that trace and put in a jumper, which pretty much
+  requires "return to Bdale for rework".  We should fix this for a future PCB
+  revision.
+
+2011.09.12
+- chatted with Adrian some yesterday.  He likes a Bosch pressure sensor that
+  is DK 828-1005-1-ND .. i2c output, similar range to our current part but
+  smaller, around $5 at our build quantities.
+
+2011.12.10
+- the Johanson balun/filter for 70cm use with cc1111 is DK 712-1540-1-ND
+  uses less PCB area, but lower performance than the discrete approach
+
+2013.01.04
+- noodling over TM v2.0 .. baro sensor will be hard to handle on cc1111.  So,
+  how about 48-pin version of STM32L, cc110L radio, ms5607 and MMA665X accel.
+  Move to the faster lipo charger, too.
+	radio / flash on spi2, sensors on spi1, baro on spi1 alternate pins
+
+2013.05.02
+- serious stab at what should be on TeleMetrum v2 .. used cc115L section from
+  TeleGPS since I didn't have a cc110L data sheet on the plane .. hope it's
+  similar .. need to update to transceiver, not just transmitter!
+