Projects Document 780-v23
- Document #:
- Document type:
- General Documentation
- Submitted by:
- David Christian
- Updated by:
- Shou Miyasaka
- Document Created:
- 10 Nov 2009, 15:43
- Contents Revised:
- 01 Jul 2011, 07:50
- Metadata Revised:
- 18 Jan 2012, 11:29
- Front-end card and level adapter for SeaQuest drift chambers. Version 4 of the ASDQ card has DC coupled inputs (no transformers, no capacitors) and only one "ground."
Design by Sten Hansen.
The ASDQ digital outputs are the open collectors of a "long tail pair." When pulled up to a voltage sufficiently greater than -3V (the negative rail of the ASDQ output circuit), 3mA flows through one or the other of an output pair. The level adapter board terminates each side through 50 ohms to approximately .6V. The resulting logic levels at the input to the LVDS receiver chip are ~0.6V & ~0.45V.
The level adapter also provides voltages, receives signals, & facilitates tests of the ASDQ-based front end cards.
The level adapters will be held in a 9U enclosure and be powered by 24V. The level adapters will be controlled over Ethernet. The first card in the crate will be connected to an Ethernet cable; subsequent cards will receive control signals via a daisy chain of telephone-style cables. The ASDQ test pulse signal will be generated in response to a command and/or by a TTL (3.3V) signal input to the first level adapter. The TTL signal will be daisy chained to the rest of the cards in the 9U enclosure with short lemo cables. The last card in the chain will require a 50 ohm termination.
- Other Files:
- ASDQ pcb rev-4 layout (pdf) (asdq_v4_layout.pdf, 615.3 kB)
- Cost Estimate (WireChamberElectronicsCost.xls, 23.0 kB)
- Current capacity of Amp pins used for LS crate backplane & for Burndy pins used for 24V PS output (burndy pin_socket current capacity.eml, 1.8 kB)
- General info on fab of level shifter crate power back plane (Seaquest LA backplane_Ccard_general_info.doc, 70.0 kB)
- General info on fab of level shifter rev D (MSWord) (Leveladapter revD_card_general_info.doc, 70.0 kB)
- Level Adapter (Rev D) Gerber files (zip) (RevD_LevelAdapter_20110406_mfg.zip, 346.3 kB)
- Level adapter rev D layout (pdf) - All, top, bottom, power, ground (All.pdf, 798.5 kB)
- Level shifter channel order (ppt) (LevelShifter_channel_order.ppt, 796.5 kB)
- Level shifter crate power back plane Gerbers (zip) (seaquestBPpcb.zip, 39.1 kB)
- Level shifter crate power back plane layout (bpall.pdf, 37.0 kB)
- Level shifter crate power back plane schematic (Backplane_shematic.pdf, 16.3 kB)
- Line drawing of ASDQ system power (ASDQSystempower.ppt, 115.5 kB)
- Line drawing of level shifter power supply box (LevelAdapterPS.pdf, 30.6 kB)
- MTTY (for USB com w/level shifters) - default port = 7 (Term07.exe, 407.0 kB)
- Package for electrical safety (ASDQSystempower_2.pdf, 764.8 kB)
- Parts list & cost estimate for ASDQ card (v3) (Part List for 8 Channel ASDQ_V3 card.xls, 25.5 kB)
- Parts list & cost estimate for Level adapter (rev D) (LEVELADAPTERD_bom_final.xls, 330.0 kB)
- QC by Grass & Shou of ASDQ cards - 12 bad out of 709 tested (asdqcheck.xls, 83.5 kB)
- Windows drivers to allow USB com (virtual port 6) through MTTY (usb_dev_serial_win2k.inf, 1.4 kB)
- oac = Open a Connection? (for Ethernet communication on windows if telnet is not available) (oac.exe, 208.1 kB)
- Dummy load cards made:
2 60 ohm 1/8 watt resistors in parallel +3V--GND
4 78 ohm 1/8 watt resistors in parallel -3V--GND
should be about 2x ASDQ card current from each bias voltage.
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