Keith found gps active antennas with cable to U.FL connectors and Molex sells
cables with U.FL to bare leads, so this should cover the bases.
-- TelePyro doesn't need a CPU. How about an SPI to I2C converter chip with
- GPIO lines and an I2C ADC chip?
+- TelePyro doesn't really need a CPU. How about an SPI to I2C converter chip
+ with GPIO lines and an I2C ADC chip? Cheaper and easier than a PIC?
+
+ PIC16F882 in SSOP-28 is $2.10 per, 1.41 @ 25 units
+ -- PIC16F883 is $2.12, PIC16F886 is $2.32, have better memories
+ CP2120 in QFN-20 is $2.41 per, 2.27 @ 25 units
The Silabs CP2120 has 8 gpio lines but is only available in QFN20. The NXP
part I discovered earlier, the SC18IS600, has 4 full gpio lines and 2 lame-o
- another way to think about all this is that I could panelize a set of boards
all done in 2 layers, then treat that as a sub-panel I put N copies down of
to fill up a 33each.com max panel size.
+
+2009.10.16
+- move to AT45DB161D 16-megabit SPI "DataFlash" EEPROM from Atmel?
+ 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.
+