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I need to up-translate two complementary 2.5 V signals to 5 V. I am looking for a circuit which can do this and which consumes ultra-low static power. I tried to design one, using 4 MOSFETs as shown below: enter image description here

The circuit uses 4 MOSFETs in a cross coupled configuration to generate the desired signals. However, I was unable to reduce the shoot through current in the MOSFETs beyond a point (Large values of R1 and R2 affects my output rise time) and the circuit is still consuming close to 50 uW at 5V VDD. I am using the output of this circuit to drive other MOSFETs which have a combined capacitance of 1nF. I want the total power consumption of this driver to be less than 10 uW. So, I searched for level shifting ICs on Digikey's and Mouser's websites, but unfortunately couldn't find a part matching my requirement. I found a part from NXP on their website, however they haven't started shipping it yet. I am hoping if somebody could suggest me a better circuit or provide an alternative to the IC I am looking for. Thanks in advance.

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  • \$\begingroup\$ Look here: google.nl/… Figure 2 shows a proper levelshifter that consumes zero power when static. \$\endgroup\$ – Bimpelrekkie Apr 7 '16 at 6:08
  • \$\begingroup\$ Also TI has plenty of voltage level translators see: ti.com/logic/docs/… Also see this selection guide: ti.com/lit/ml/scyb018h/scyb018h.pdf \$\endgroup\$ – Bimpelrekkie Apr 7 '16 at 6:10
  • \$\begingroup\$ @FakeMoustache I am using the same configuration of the level shifter which is shown in Fig. 2 & Fig. 4 of the Analog Devices link you sent me. \$\endgroup\$ – ashare Apr 7 '16 at 6:24
  • \$\begingroup\$ And still you're not getting (almost) zero static power consumption while the circuit from my link does meet that requirement (I know, because I designed many of them). Can you guess why ? Hint: the circuit is mainly used on-chip. \$\endgroup\$ – Bimpelrekkie Apr 7 '16 at 6:34
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    \$\begingroup\$ That's also related to the transistors. You're using switching transistors which have a huge Cgs (compared to the ones used on a chip). Also you should have much weaker PMOS than NMOS, something you cannot do so easily off-chip. To do this function efficiently you have to use an IC to do the job. \$\endgroup\$ – Bimpelrekkie Apr 7 '16 at 6:57

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