The FMC DIO 10i8o is an I/O card in FMC form-factor. This card uses a
low-pint count (LPC) connector.
It's 10 inputs use fast differential comparators (propagation delay < 1
ns) with 12-bit DAC to set references. The 8 outputs are LVTTL level.
To get rid of the N12V0 100mV ripple, place the not-mounted C1 capacitor of 150pF. This will render the LM2611 (IC2) feedback loop stable.
About 20% of the V4 cards have a too high ripple for the N2V9 rail, change R19 from 10k to 15k for all.
IC18_IC has its D1 (pin10) and D2 (pin9) pins floating because of a not-connected via, undetected by Altium (problem might be on previous versions as well!). When activating Ch4 and Ch5 50 Ohm termination, both channels will be electrically connected! Solder a small wire between the via and the neighbouring GND pad. Bug reported
Modifications wrt V3:
OUTS_EN_n signal added to ensure outputs at high-impedance during configuration/powering
wired to MAX9122, not fully working as expected; should use OEn input from 74LVC2244 drivers instead
doubled output drivers for higher output voltage when terminated in 50 Ohms (now 2.4V)
unintended swap of last 4 output signals (out 4-5-6-7 wired to 7-6-5-4)!
output ESD protection (TVS) added
all comparator LVDS termination resistors now at 470 Ohms
DAC RC filter improved for more precise 1/4 division; equivalent resistance matching for comparator bias currents compensation
SPI test pads added
N2V9 rail resistor changed to 10k for stability
corrected i2c note
i2c temperature sensors added
N2V5 base resistor added to reduce HF noise (110mV -> 30mV)
P4V5 HF noise reduced by adding 10uF+100nF+1nF caps