5 This is a photo of our original board with serial port for off-board GPS,
6 without the big off-board 1000uF cap from the original ejection circuit:
8 <a href="v0.1/loadedpair.jpg"> <img src="v0.1/loadedpair-thumb.jpg"></a>
10 The differences between v0.1 and later boards were substantial:
12 * 2.5 x 1 inch board with all parts mounted on one side
13 * 4-pin PicoBlade serial port connector for attachment of external GPS module
14 * USB connector projected approximately 3mm over the edge of the board
15 * Debug connector used 4 IC socket pins on 100 mil centers
16 * no companion board interface
17 * 50ma LDO regulator on early boards, later boards used a 100ma part
18 * [Microchip 25LC1024](http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en520389) CMOS serial EEPROM instead of DataFlash
21 * [Microchip MCP9700A](http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en027103) discrete temperature sensor
22 * used 1000uF electrolytic capacitor charged to 5V for pyro supply
23 * two LEDs instead of one attached to CPU
25 The elimination of the discrete temperature sensor and second LED were
26 necessary to support the companion board interface added in v0.2.
28 The v0.1 artwork had three issues, two of which required physical rework
29 on each board. All of these issues were fixed in v0.2.
31 * The USB connector footprint was placed wrong, so that the
32 connector hung out over the edge of the board instead of being
34 * We needed chip select on the SPI memory. To fix that, we gave up the
35 ability to put the accelerometer into self-test mode and used that
36 GPIO line to pull chip select on the memory, which required two
38 * The igniter sense circuits each needed a second resistor to
39 complete the voltage divider so our 3.3V CPU ADC could read the
40 5V ejection voltage. This was fixed by changing two resistor
41 values, and tacking two additional resistors onto the board
42 with jumpers to ground.
44 The schematics and PCB artwork for this version as of the working-v0.1 tag
45 are available here are pdf copies for easy reference:
47 * [schematic](v0.1/telemetrum.pdf)
48 * [pcb artwork](v0.1/telemetrum.pcb.pdf)
49 * [bill of materials](v0.1/telemetrum.bom)
53 These are photos of our second version, which included the integrated Venus
54 GPS receiver, but with a passive patch antenna that turned out to have
55 disappointing performance due to our many PCB geometry constraints. It also
56 used a voltage regulator with less capacity which we felt was marginal for
57 supporting the companion boards we have planned:
59 <a href="v0.2/cimg5164-cropped.jpg"> <img src="v0.2/cimg5164-thumb.jpg"></a>
60 <a href="v0.2/cimg5171-cropped.jpg"> <img src="v0.2/cimg5171-thumb.jpg"></a>
62 Other than cleaning up the silkscreen, the differences between v0.2 and
63 v1.0 boards were really quite small:
65 * 100ma LDO regulator instead of the current 150ma part
67 * different value for C36 reset capacitor
69 The schematics and PCB artwork for this version are on the v0.2 branch in
70 our git repository, here are pdf copies for easy reference:
72 * [schematic](v0.2/telemetrum.pdf)
73 * [pcb artwork](v0.2/telemetrum.pcb.pdf)
74 * [bill of materials](v0.2/partslist.csv)
78 These are photos of our third version, which was the basis of our first
79 production build. These were sold between April and December 2010, and
82 <a href="v1.0/cimg5972-crop.jpg"> <img src="v1.0/cimg5972-thumb.jpg"></a>
83 <a href="v1.0/cimg5974-crop.jpg"> <img src="v1.0/cimg5974-thumb.jpg"></a>
85 The differences between v1.0 and v1.1 were small:
87 * different flash memory part due to supplier availability problems
88 * updated reset circuit to improve reliability at temperature extremes
89 * changed the GPS antenna footprint to eliminate the large through-hole
90 originally intended for use with a passive patch
91 * irq line eliminated from the companion port
92 * an additional resistor divider added to allow sampling the 5V supply
94 The schematics and PCB artwork for this version are on the v1.0 branch in
95 our git repository, here are pdf copies for easy reference:
97 * [schematic](v1.0/telemetrum.pdf)
98 * [pcb artwork](v1.0/telemetrum.pcb.pdf)
99 * [bill of materials](v1.0/partslist.csv)
103 <a href="v1.1/telemetrum-v1.1-thside.jpg"> <img src="v1.1/telemetrum-v1.1-thside-thumb.jpg"></a>
104 <a href="v1.1/telemetrum-v1.1-smtside.jpg"> <img src="v1.1/telemetrum-v1.1-smtside-thumb.jpg"></a>
106 For those who don't have ready access to the gEDA suite, here are pdf snapshots
107 of the files for Production PCB version 1.1 in more easily readable form.
109 * [schematic](v1.1/telemetrum.pdf)
110 * [pcb artwork](v1.1/telemetrum.pcb.pdf)
111 * [bill of materials](v1.1/partslist.csv)
115 Our current production version.