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CD4010B-Q1: VOL Max, VOH Min, VIL Max and VIH Min when Vdd=5V and Vcc=3,3V?

Part Number: CD4010B-Q1
Other Parts Discussed in Thread: TXU0104, SN74LXC8T245

I would like to use CD4010B-Q1 to translate digital lines from a 3,3V sensor to 5V uC

in The datasheet in the table "STATIC ELECTRICAL CHARACTERISTICS" there are VOL Max, VOH Min, VIL Max and VIH Min specified only for Vdd=5, 10 and 15V 

in the "RECOMMENDED OPERATING CONDITIONS" Vdd is specified as at least 3V so I assume this IC can be used to translate 3,3V to 5V levels.

How to obtain values for VOL Max, VOH Min, VIL Max and VIH Min when Vdd=5V and Vcc=3,3V?

best regards

Arek

  • CD4000 devices are optimized for higher voltages. There are no guaranteed electrical characteristics for supplies below 5 V.

    How many signals do you actually have? It would be a better idea to use a low-voltage level shifter like the TXU0104 or SN74LXC8T245.

  • CD4000 devices are optimized for higher voltages but for this particular one datasheet allows operation down to 3V. I would like to supply it from 3,3V which within recommended operation conditions with a decent margin.

    CD4010B-Q1 costs €0.096 while TXU0104  €0.249 and SN74LXC8T245 is €0.341 a piece so there is a good reason for choosing  the CD4010B-Q1.

    There are 3 signals from the 3,3V Sensor which I would like to translate to 5V levels (SPI MISO and two interrupts).

  • Yes, the datasheet guarantees that it will work correctly at 3 V. However, there are no guarantees whatsoever for the drive strength at 3 V, so you can connect its outputs only to high-impedance CMOS inputs. Furthermore, you do not know the maximum frequency (at 5 V, the worst-case propagation delay is 200 ns, corresponding to 5 Mbps; at 3.3 V, it will be much worse).

  • You are right - drive strength and propagation delay will get worse - the question is: how much?  I hope TI is able to provide these information. If they declare "it works down to 3V supply voltage" then there has to be a way to estimate parameters near to this supply voltage.

  • These devices were acquired from Harris 23 years ago. If the information is not in the datasheet, it does no longer exist.