Market size of new, non-legacy, 5V ICs ?

Outside of the hobbyist ecosystem, what is the actual market size for new, non-legacy, ICs with a maximum Vcc of ~5V ?

I've just picked up a few of the new Microchip 1Mbit SPI RAM ICs:

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and I was utterly amazed to see them available in this 5V capable packaging.

This is a product range which until now has topped out at 3.6V maximum and the inputs were not even 5V tolerant on those earlier devices. Yet here in

2013, Microchip has released a new set of parts in this range which are not only 5V I/O tolerant, but actually run at 5V as well. To my mind, it would be like Microchip, say, suddenly deciding to create a PIC32 range which runs at 5V.

They clearly would not do this unless there was a market for them, but I am just puzzled what that market is. If this was for the hobbyist market only I would have expected them to carry on saying "use one of our 3.6V devices with a level shifter".

Even in the hobbyist market however many of the newer devices you might want to interface with are increasingly 3.3V only (and without 5V tolerant inputs either in many cases) so even as a hobbyist I am moving down into the 3.3V MCU world anyway.

Observations/non-hobbyist viewpoints welcome. :-)

Simon.

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Simon Clubley, clubley@remove_me.eisner.decus.org-Earth.UFP 
Microsoft: Bringing you 1980s technology to a 21st century world
Reply to
Simon Clubley
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There are few areas where 5V power is preferred:

  • Most of CAN transceivers require 5V.
  • Power electronics; i.e. high/low side switches, FET drivers etc. often require 5V.
  • There is a lot more flexibility and choice with analog electronics running on 5V rather then 3.3V.

Summarizing, in applications like industrial/automotive controllers, 5V has its place.

Vladimir Vassilevsky DSP and Mixed Signal Designs

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Reply to
Vladimir Vassilevsky

Thanks. Those are some interesting examples I had not thought about.

With those examples in mind, I will now modify my original question to instead ask only about ICs which would be used for mainly digital signalling or interfacing purposes such as the SPI RAM IC that started me thinking about this in the first place. :-)

Even though Microchip is a hobbyist friendly manufacturer, I'm still not seeing the market justification for moving from 3.6V to a 5V capable setup in 2013 for what is a purely digital IC without legacy issues.

Simon.

PS: In case anyone is wondering why it matters, the answer is that it doesn't really. It's just that it's so at odds with all my recent experiences of interfacing to devices that are 3.3V only (and in most cases were not even 5V tolerant) that I was just trying to understand what was going on.

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Simon Clubley, clubley@remove_me.eisner.decus.org-Earth.UFP 
Microsoft: Bringing you 1980s technology to a 21st century world
Reply to
Simon Clubley

We use 3.3V CAN transceivers, which are now very common.

That's the big one that I see. Lots of FETs/FET drivers, switches, solid-state relays, etc., are 5V on the logic side.

I see that a bit, but most new parts are 3.3V (or have separate supplies for the interface and the analogue parts).

What is really missing is a decent family of basic logic chips that work well with both 3.3V and 5V (and preferably with lower voltages too). With most logic chips, driving 5V inputs with 3.3V outputs will work - but it is outside their specifications for minimum voltage levels. So if you've got a 3.3V micro and you want to use a logic chip (say, a serial-in parallel-out shift register as an SPI port expander) to drive some FETs, you have to have a level shifter as well as the shift register. Alternatively, you have to power your shift register from something weird like 4.2 V.

Reply to
David Brown

If you have to employ parts that need +5V, then it makes sense to run entire system from +5V. Rather then dealing with separate power supplies and level shifting issues. There are quite a few cases where +5V is preferred or required; so here is my point.

Reply to
Vladimir Vassilevsky

The last time I looked at automotive devices, they were still common in

5V. Is that not true so much now?
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Rick
Reply to
rickman

What about USB-powered gadgets?

Reply to
Paul Rubin

There are plenty of automotive parts in 5V. The challenge is not the 5V parts in themselves, or the 3.3V parts - it is connecting them together in a compact and efficient way (i.e., without having to have lots of dedicated level converters). It is a pain that there are /no/ good logic families that run from 5V and are 3.3V tolerant (i.e., guaranteed to treat even low 3.3V inputs as "high"), and /no/ good 3.3V logic families with 5V tolerant inputs. There are many families that work well enough in practice - but "works during testing" is not good enough for many applications.

Of course, if I'm wrong here then I would love to be corrected!

Reply to
David Brown

For 3.3V to 5V we often use 74HCT. I always check the datasheets, and I can't remember a case where the levels did not work out, even in the extreme temperature specs. The (NXP) 74HCT1G02 for example has a high input level of 2.0V over the -40C to +125C range. That even works with, for example, an Analog Devices BF522 at 3.0V VDDext which has a minimum high output of 2.4V. Should even work with VDDext = 2.25V with Voh=2.0V.

Don't use the 'HC' family for this purpose of course, the levels are totally different. (NXP) 72HC1G02 @ 4.5V: Vih = 3.15V.

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Stef    (remove caps, dashes and .invalid from e-mail address to reply by mail) 

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Reply to
Stef

5V in automotive is also an issue of noise tolerance being better at 5V.

w..

Reply to
Walter Banks

Since the I/O voltage for USB is 3.3V it's not a contender, except for

5V regulators.
Reply to
Anssi Saari

You certainly can use HCT, and it would work for 3.3V to 5V conversion. However keep in mind that the quiescent current in "1" state is going to be about 1mA per gate.

Vladimir Vassilevsky DSP and Mixed Signal Designs

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Reply to
Vladimir Vassilevsky

Here you go:

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Quad buffer with 5V tolerant inputs and outputs when run off 3.3V. I think the other members of the family are also tolerant of 5V inputs.

I used the single-gate versions of these quite often for level shifting 5V inputs to match 3.3V-only logic

OTOH, finding 3.3V logic guaranteed to provide the 3.15V minimum for 74HC logic is more difficult. You might have to go to the 74LS series in that case. It runs off 5V, but, accepts any level above 2V as a high level input. Whether you accept the 74LS series as a 'good' logic family probably depends on whether you started building logic circuits in this century or the last! ;-)

One of the things I like about the STM32 MPUs is that the digital I/O is 5V tolerant. For fairly slow and lightly loaded output signals the pins go to very near 3.3V. If I'm in doubt, I guess I could activate the pullup resistor on the I/O port to get a few more millivolts at the output.

Mark Borgerson

Reply to
Mark Borgerson

You mean like 74HCT, 74ACT, etc?

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Rob Gaddi, Highland Technology -- www.highlandtechnology.com 
Email address domain is currently out of order.  See above to fix.
Reply to
Rob Gaddi

That's not as simple as you might think; just because the MCU at the heart of the USB gadget works in a USB bus powered mode there is no guarantee that the MCU itself supports or tolerates a 5V Vcc.

One example that does support 5V bus powered mode is the PIC18F14K50; it has a internal 3.3V LDO voltage regulator to drop the 5V down to 3.3V.

The PIC32MX (in device mode) appears to be a far more interesting case but note my power supply knowledge here is based purely on reading the PIC32 FRM and the datasheet of a USB capable PIC32MX part.

The PIC32MX has absolutely no support for been directly powered by a 5V source and a quick look through the FRM and the DS didn't reveal any hints for using a PIC32MX part in bus powered mode.

However, I also didn't see any reason why the PIC32MX part could not be connected to the USB +5V line via a 3.3V LDO regulator, hence making the part USB bus powered capable even though it doesn't support 5V directly.

BTW, when running in host mode instead of device mode, the PIC32MX requires a external 5V source to power the USB +5V line; it cannot supply the 5V itself directly.

Simon.

--
Simon Clubley, clubley@remove_me.eisner.decus.org-Earth.UFP 
Microsoft: Bringing you 1980s technology to a 21st century world
Reply to
Simon Clubley

If you think that is 'strange' then perhaps I should not mention the new Infieon, 32 bit XMC1000, that operates 1.8-5.5V ??

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Or mention Fujistu, or Nuvoton, who also offer 5V, 32 bit parts ??

There are plenty of instances where Wide Vcc is smarter, and so will sell more.

Direct Drive of Power MOSFETS, is a very common, widespread industrial requirement, and 5V-operate parts, can do that. Also common, is the need to read 5V signals from sensors

Plenty of 8 bit uC offer wide Vcc, so anyone pitching a 32 bit uC will need to offer the same Vcc range. Some Vendors 'get this', others simply 'hope' designers will follow their hype. (and some 32 bit uC are already EOL, the very ones claimed to be 8-bit-killers, at release....)

A lot of new uC now, in both 8 and 32 bit, are wide Vcc, and this done on fine/shrink process, and using on-chip regulators.

There was a brief time, when vendors put On-Chip-regulation in the 'Too hard' basket, but that Infineon part is 65nm, with a regulator.

So there are a lot of reason to offer 5V parts, and very few excuses left, to NOT do this. Expect to see more of this.

-jg

Reply to
j.m.granville

There are various combinations of logic families that can work together for level conversion - such as the ones you mention here, and the 74HCT mentioned by others. But in each case, this only covers some types of chips. I found I could get parts that had the voltage levels and tolerances I wanted /or/ the functionality I wanted - but not both. In once case I wanted a serial-in, parallel-out latch. The 74HC595 is functionally ideal - except that at 5V supply it needs 3.5V for input high. A 74HCT595 would be possible, but it doesn't exist.

Would it really be so hard for a manufacturer to have a series that supports a range of VCC (say 2V to 6V, like HC), with TTL-compatible inputs (= 2.0V is high, like HCT) and near rail-to-rail outputs (obviously for a limited current range - like HC), and with a fairly complete range of the 74 series? All that would be needed is a few extra transistors on the inputs of an HC device, costing microdollars per chip at today's prices. The latency would marginally increase, as would the power consumption, but only slightly - and the devices would cover the great majority of common use cases. Most other logic families could be dropped, except for extremes of low voltage, high speed, or low power. It would be a great saving for the manufacturer, the distributors, purchasers and developers.

Reply to
David Brown

Here you go. 74HCT595. Vih

Reply to
Arlet Ottens

Yes, don't seem to be too hard to get hold of!

Perhaps David was thinking of something else...

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John Devereux
Reply to
John Devereux

It's certainly possible that I was thinking about something else - it was a while ago when I worked on the project that needed such chips. (And of course it is too late now - the board was completed using level converters as well as the logic chips.)

However, looking at the nxp data sheet I see that the HCT version needs

3.15V at 4.5V - and presumably therefore 3.5V and 5V for its inputs. In other words, it is useless for driving with 3.3V supplies. It seems that in this respect nxp's HCT family are different from TI's HCT family (which is the ones I originally looked at).

Maybe there is a 74x595 out there somewhere which will work properly from 3.3V inputs and 5V supplies, but I still haven't found it.

Reply to
David Brown

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