Added adc-iq-2185-xp2 BOM, schematic PDF, and README with license.

baseband_digitizer/adc-iq-2185-xp2/README.md

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+adc-iq-2185-xp2
+===============
+
+A baseband digitizer board that can capture quadrature signals at 80MHz or
+more, process them in an FPGA, and transmit the sample stream to a host
+computer over high-speed USB (480Mbps).
+
+This design consists of a Linear Technology LT2141-12 (80MHz, two-channel
+ADC), a Lattice XP2 FPGA, and an FTDI FT2232H FIFO-to-USB interface IC. [One
+prototype](http://www.sharebrained.com/2012/05/10/progress-on-my-sdr/) device
+has been built from this hardware, and is working very well when interfaced
+with my ADRF6850 front-end board.
+
+I did have to modify the adrf6850-breakout to allow setting the baseband
+output DC offset to a level appropriate for the LT2141's inputs. I also
+placed 100 Ohm resistors in front of the ADC input filters, to set the
+impedance seen by the ADRF6850 baseband outputs. The ADRF6850 board was
+configured with four-pole Butterworth low-pass filters.
+
+The ADC can be scaled considerably, because the LTC2141-12 is pin-compatible
+with a wide range of converters. Linear's range goes down to 12 bits at 25MSps
+(LTC2140-12) and up to 125MSps at 16 bits (LTC2185).
+
+Status
+======
+
+This board has been fabricated and assembled. It was used to receive these
+signals:
+
+* POCSAG and FLEX pager broadcasts
+* 315 MHz and 433 MHz automotive tire pressure monitors
+* Aviation voice transmissions
+* ATSC television
+* Broadcast FM (88 - 108 MHz)
+
+The FPGA is configured as a 2:1 "F5" half-band filter followed by a 49-tap,
+5:1 decimation FIR filter. Output samples are at 8MHz, complex, 16-bit. USB
+data rate is 32 million bytes per second. The libftdi-1.0 library's
+asynchronous support was used to support this high data rate.
+
+I faked GNU Radio support by creating a UNIX FIFO file and piping the sample
+output of my libftdi program into the pipe. Then, I used a GNU Radio file
+source to read from the pipe. It's pretty reliable, except for occasionally
+unpredictable I/Q phase, which I think is caused by extra, unread data sitting
+in the FIFO between runs of the GNU Radio graph.
+
+Bill of Materials
+=================
+
+See the included adc-iq-2185-xp2-bom.csv. I believe it's up-to-date with the
+components and values I used in my last build of this board. But do re-check
+against the appropriate datasheets.
+
+Requirements
+============
+
+* [EAGLE 5.11 Hobbyist, Standard, or Professional]
+  (http://www.cadsoftusa.com/shop/pricing/)
+
+Because this design uses four PCB layers, EAGLE "freeware" version
+will not be useful for editing this design.
+
+Files
+=====
+
+* adc-iq-2185-xp2.sch:
+
+    Schematic for circuit board, drawn in EAGLE 5.11.
+
+* adc-iq-2185-xp2-sch.pdf:
+
+    Schematic for circuit board, in Adobe PDF format.
+
+* adc-iq-2185-xp2-bom.csv:
+
+    List of components used in the circuit board, including recommended vendors
+    and prices.
+
+* adc-iq-2185-xp2.brd:
+
+    Circuit board layout, drawn in EAGLE 5.11.
+
+* adc-iq-2185-xp2.dru:
+
+    TODO: MISSING, need to recreate and add to repository
+
+    EAGLE design rules used to validate schematic and PCB.
+
+* adc-iq-2185-xp2-laen4.cam:
+
+    EAGLE CAM file used to generate Gerber RS-274X files for
+    circuit board production via
+    [Laen's four-layer PCB Order]
+    (http://dorkbotpdx.org/wiki/pcb_order).
+
+License
+=======
+
+This hardware design is licensed under a
+[Creative Commons Attribution-ShareAlike 3.0 Unported License]
+(http://creativecommons.org/licenses/by-sa/3.0/).
+
+The associated software is provided under a BSD two-clause license:
+
+Copyright (c) 2011, ShareBrained Technology, Inc.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+o Redistributions of source code must retain the above copyright notice, this
+  list of conditions and the following disclaimer.
+
+o Redistributions in binary form must reproduce the above copyright notice,
+  this list of conditions and the following disclaimer in the documentation
+  and/or other materials provided with the distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.
+
+Contact
+=======
+
+ShareBrained Technology, Inc.
+
+<http://www.sharebrained.com/>

baseband_digitizer/adc-iq-2185-xp2/hardware/adc-iq-2185-xp2-bom.csv

@@ -0,0 +1,37 @@
+Ref Des,Mfr,Mfr Part,Desc,Vendor,Vendor Part,Qty
+"C1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,26,27,29,30,31,34,35,36,38,40,41,51,52,53,54,55,56,57,61",Murata,GRM155R61A104KA01D,CAP CER 0.1UF 10V 10% X5R 0402,Digi-Key,490-1318-1-ND,41
+"C23,24,25",Taiyo Yuden,JMK107BJ475MA-T,CAP CER 4.7UF 6.3V 20% X5R 0603,Digi-Key,587-1255-1-ND,3
+C28,AVX,W2L14Z225MAT1S,CAP CER 2.2UF 4V 20% X7S 0508,Digi-Key,478-5502-1-ND,1
+"C32,39",Taiyo Yuden,JMK105BJ225MV-F,CAP CER 2.2UF 6.3V 20% X5R 0402,Digi-Key,587-1453-1-ND,2
+"C33,37,59,60",Murata,GRM1555C1H120JZ01D,CAP CER 12PF 50V 5% NP0 0402,Digi-Key,490-1279-1-ND,4
+"C42,43,47,49",Taiyo Yuden,JMK107BJ225KA-T,CAP CER 2.2UF 6.3V 10% X5R 0603,Digi-Key,587-1254-1-ND,4
+"C44,45,46,48",Taiyo Yuden,LMK212BJ106KG-T,CAP CER 10UF 10V 10% X5R 0805,Digi-Key,587-1300-1-ND,4
+C50,Kemet,T491D106M025AT,CAP TANT 10UF 25V 20% 2917,Digi-Key,399-3767-2-ND,1
+C58,,,250V 0402,,,
+"FB1,2,3,4",TDK,MPZ1608S601A,FERRITE CHIP BEAD 600 OHM SMD,Digi-Key,445-2205-1-ND,4
+J1,Hirose,UX60-MB-5ST,CONN RECEPT MINI USB2.0 5POS,Digi-Key,H2959CT-ND,1
+"J2,4,14",,,,,,
+J3,,,,,,
+"J5,6,7,8",Emerson,142-0701-801,Connector; SMA Jack; Solder Pin; Straight,Allied,528-0238,4
+J9,CUI,PJ-102A,CONN JACK POWER 2.1MM PCB,Digi-Key,CP-102A-ND,1
+"J10,11,13",,,,,,
+J12,,,,,,
+"R1,2,5,6,18,19,20,22,24,25,26",Vishay,CRCW040210K0JNED,RES 10K OHM 1/16W 5% 0402 SMD,Digi-Key,541-10KJCT-ND,11
+R3,Yageo,RC0402FR-071ML,RES 1.00M OHM 1/16W 1% 0402 SMD,Digi-Key,311-1.00MLRCT-ND,1
+R4,Panasonic,ERJ-2RKF1202X,RES 12.0K OHM 1/10W 1% 0402 SMD,Digi-Key,P12.0KLCT-ND,1
+"R7,8,9,10,14",Yageo,RC0402FR-0724R9L,RES 24.9 OHM 1/16W 1% 0402 SMD,Digi-Key,311-24.9LRCT-ND,5
+"R11,38",Yageo,RC0402FR-071KL,RES 1.00K OHM 1/16W 1% 0402 SMD,Digi-Key,311-1.00KLRCT-ND,2
+"R12,17",Yageo,RC0402FR-072K2L,RES 2.20K OHM 1/16W 1% 0402 SMD,Digi-Key,311-2.20KLRCT-ND,2
+"R13,21",Panasonic,ERJ-2RKF4701X,RES 4.70K OHM 1/10W 1% 0402 SMD,Digi-Key,P4.70KLCT-ND,2
+"R15,16",Bourns,CR0402-J/-000GLF,Thick Film Resistors - SMD Zero Ohm 5%,Mouser,652-CR0402-J/-000GLF,2
+"TP1,2",Mill-Max,2501-2-00-80-00-00-07-0,"TERMINAL PIN TURRET .109"" SOLDER",Digi-Key,ED90581-ND,2
+U1,Lattice,LFXP2-5E-5TN144C,IC FPGA 5KLUTS 100I/O 144-TQFP,Digi-Key,220-1250-ND,1
+U2,Linear,LTC2143CUP-12,IC ADC DUAL 12BIT 80 MSPS 64-QFN,,,1
+U3,FTDI,FT2232HL,IC USB HS DUAL UART/FIFO 64-LQFP,Digi-Key,768-1024-1-ND,1
+U4,Analog,ADP150AUJZ-3.3-R7,IC REG LDO 3.3V .15A TSOT-5,Digi-Key,ADP150AUJZ-3.3-R7CT-ND,1
+U5,Analog,ADP151AUJZ-1.8-R7,IC REG LDO 1.8V 200MA 5TSOT,Digi-Key,ADP151AUJZ-1.8-R7CT-ND,1
+U6,Torex,XC6222B121MR-G,IC REG LDO 1.2V SOT-25,Digi-Key,893-1139-1-ND,1
+U7,Torex,XC6222B331MR-G,IC REG LDO 3.3V SOT-25,Digi-Key,893-1143-1-ND,1
+U8,Microchip,93LC46C-I/SN,IC EEPROM 1KBIT 3MHZ 8SOIC,Digi-Key,93LC46C-I/SN-ND,1
+X1,Connor-Winfield,CWX813-080.0M,OSC 80.0000MHZ 3.3V +-25PPM SMD,Digi-Key,CW546CT-ND,1
+X2,TXC,7M-12.000MAAJ-T,CRYSTAL 12.000 MHZ 18PF SMD,Digi-Key,887-1121-1-ND,1