Searching \ for '[PIC] Opinion on these devices...' in subject line. ()
Make payments with PayPal - it's fast, free and secure! Help us get a faster server
FAQ page: www.piclist.com/techref/microchip/devices.htm?key=pic
Search entire site for: 'Opinion on these devices...'.

Exact match. Not showing close matches.
PICList Thread
'[PIC] Opinion on these devices...'
2009\06\08@150346 by solarwind

picon face
I'm planning to order a whole bunch of PIC 18 F 26/46 J 50. The 46
devices are just higher pin count versions of the 26 devices I assume.
What are your opinions on these devices? I'm going to build my network
with these. Will also be ordering some PIC32s.

-- [ solarwind ] -- http://solar-blogg.blogspot.com/

2009\06\08@160935 by olin piclist

face picon face
solarwind wrote:
> I'm planning to order a whole bunch of PIC 18 F 26/46 J 50. The 46
> devices are just higher pin count versions of the 26 devices I assume.
> What are your opinions on these devices? I'm going to build my network
> with these.

Do you really need 3.3V operation?  If not, I'd go with generic 5V parts
like the 18F2620 and '4620.


********************************************************************
Embed Inc, Littleton Massachusetts, http://www.embedinc.com/products
(978) 742-9014.  Gold level PIC consultants since 2000.

2009\06\08@172322 by solarwind

picon face
On Mon, Jun 8, 2009 at 8:57 PM, Olin Lathrop<spam_OUTolin_piclistTakeThisOuTspamembedinc.com> wrote:
> Do you really need 3.3V operation?  If not, I'd go with generic 5V parts
> like the 18F2620 and '4620.

Actually, the 3.3V operation is something I'd rather not have.
However, these chips have everything I've wanted out of the 18F2620
that I have right now. They have peripheral pin select, integrated
RTC, 5V tolerant inputs (are they 5V tolerant on high impedance or low
impedance, by the way?) and a lot of other cool features. Also, for a
hobbyist, they seem nice because they come in cool DIP packages and
low price of only $3.30 approx. each. The 18F2620s are older and more
expensive. Price is the reason I want to stay away from 18F2620. I'm
going to buy around 10 of these so I'd rather spend $30 not $50+.

2009\06\09@010134 by William \Chops\ Westfield

face picon face
On Jun 8, 2009, at 2:23 PM, solarwind wrote:

> for a hobbyist, they seem nice because they come in cool DIP packages

the 18f46J50 does not appear to be available in DIP (or even PLCC)
Also, only a small number of the pins are marked as 5V tolerant on  
either the 28 or 44 pin chips...


> and low price of only $3.30 approx. each.

Huh.  Every once in a while Microchip shocks me by having an unusually  
low price on some particular performance/pincount point.  And they've  
done it again...

BillW

2009\06\09@024159 by Xiaofan Chen

face picon face
On Tue, Jun 9, 2009 at 1:01 PM, William "Chops" Westfield<.....westfwKILLspamspam@spam@mac.com> wrote:
>> and low price of only $3.30 approx. each.
>
> Huh.  Every once in a while Microchip shocks me by having an unusually
> low price on some particular performance/pincount point.  And they've
> done it again...
>

Actually you may be even shocked to know the price of some PIC24
and PIC32 parts if you think US$3.3 is low. The price of 32bit MCUs
(like STM32) which are much better than PIC18J are approaching
US$2 for low quantity (1k-10k) now. So do PIC24 and PIC32. But for 10pcs
price, the price is still not that low yet.

--
Xiaofan http://mcuee.blogspot.com

2009\06\09@024732 by Xiaofan Chen

face picon face
On Tue, Jun 9, 2009 at 1:01 PM, William "Chops" Westfield<westfwspamKILLspammac.com> wrote:
> On Jun 8, 2009, at 2:23 PM, solarwind wrote:
>
>> for a hobbyist, they seem nice because they come in cool DIP packages
>
> the 18f46J50 does not appear to be available in DIP (or even PLCC)
> Also, only a small number of the pins are marked as 5V tolerant on
> either the 28 or 44 pin chips...
>

Other than that, PIC18F26J50/46J50 device have USB function. If
Solarwind does not need USB function, it can be cheaper to
use other PIC18J device.

PIC24 can be an option as well.
www.microchip.com/wwwproducts/Devices.aspx?dDocName=en026374
Single piece price is at US$3.64 (DIP): PIC24FJ64GA002-I/SP

It is similar in cost to PIC18F26J50
www.microchip.com/wwwproducts/Devices.aspx?dDocName=en534041
Single piece price is at US$3.37 (DIP): PIC18LF26J50-I/SP


--
Xiaofan http://mcuee.blogspot.com

2009\06\09@180145 by solarwind

picon face
On Tue, Jun 9, 2009 at 7:47 AM, Xiaofan Chen<.....xiaofancKILLspamspam.....gmail.com> wrote:
> Other than that, PIC18F26J50/46J50 device have USB function. If
> Solarwind does not need USB function, it can be cheaper to
> use other PIC18J device.
>
> PIC24 can be an option as well.
> www.microchip.com/wwwproducts/Devices.aspx?dDocName=en026374
> Single piece price is at US$3.64 (DIP): PIC24FJ64GA002-I/SP
>
> It is similar in cost to PIC18F26J50
> www.microchip.com/wwwproducts/Devices.aspx?dDocName=en534041
> Single piece price is at US$3.37 (DIP): PIC18LF26J50-I/SP

You're right. I should start using 16 bit controllers. What's the
major differences between the 8 bit series and the 16 bit series?
What's the power consumption like? Also, whats the difference between
24F, 24H, 30DSC and 33DSC?

2009\06\09@211647 by Xiaofan Chen

face picon face
On Tue, Jun 9, 2009 at 2:41 PM, Xiaofan Chen<EraseMExiaofancspam_OUTspamTakeThisOuTgmail.com> wrote:
> Actually you may be even shocked to know the price of some PIC24
> and PIC32 parts if you think US$3.3 is low. The price of 32bit MCUs
> (like STM32) which are much better than PIC18J are approaching
> US$2 for low quantity (1k-10k) now. So do PIC24 and PIC32. But for 10pcs
> price, the price is still not that low yet.
>

Even the ARM926 MPU (with MMU) is getting pretty low in terms of cost.

Digikey pricing per 100 units:
LPC3130 (ARM9, 96KB SRAM!, EMC - No Flash) - $3,55! (90nm process)
LPC3131 (ARM9, 192KB SRAM!!, EMC - No Flash) - $4,76 (90nm process)

Digikey pricing per piece:
LPC3130 (ARM9, 96KB SRAM!, EMC - No Flash) - $5.60 (90nm process)
LPC3131 (ARM9, 192KB SRAM!!, EMC - No Flash) - $7.50 (90nm process)

--
Xiaofan http://mcuee.blogspot.com

2009\06\09@211743 by Xiaofan Chen

face picon face
On Wed, Jun 10, 2009 at 9:16 AM, Xiaofan Chen<xiaofancspamspam_OUTgmail.com> wrote:
> On Tue, Jun 9, 2009 at 2:41 PM, Xiaofan Chen<@spam@xiaofancKILLspamspamgmail.com> wrote:
>> Actually you may be even shocked to know the price of some PIC24
>> and PIC32 parts if you think US$3.3 is low. The price of 32bit MCUs
>> (like STM32) which are much better than PIC18J are approaching
>> US$2 for low quantity (1k-10k) now. So do PIC24 and PIC32. But for 10pcs
>> price, the price is still not that low yet.
>>
>
> Even the ARM926 MPU (with MMU) is getting pretty low in terms of cost.
>
> Digikey pricing per 100 units:
Should be "Digikey pricing per 500 units"
> LPC3130 (ARM9, 96KB SRAM!, EMC - No Flash) - $3,55! (90nm process)
> LPC3131 (ARM9, 192KB SRAM!!, EMC - No Flash) - $4,76 (90nm process)
>
> Digikey pricing per piece:
> LPC3130 (ARM9, 96KB SRAM!, EMC - No Flash) - $5.60 (90nm process)
> LPC3131 (ARM9, 192KB SRAM!!, EMC - No Flash) - $7.50 (90nm process)
>

--
Xiaofan http://mcuee.blogspot.com

2009\06\09@212319 by Xiaofan Chen

face picon face
On Wed, Jun 10, 2009 at 6:01 AM, solarwind<KILLspamx.solarwind.xKILLspamspamgmail.com> wrote:
> You're right. I should start using 16 bit controllers. What's the
> major differences between the 8 bit series and the 16 bit series?
> What's the power consumption like? Also, whats the difference between
> 24F, 24H, 30DSC and 33DSC?

For details you have to go to the Microchip website.
http://www.microchip.com/16bit

dsPIC30 -- old CMOS technology, 5V, high current consumption (30MIPS)
dsPIC33 -- 3.3V, lower current consumption, faster than dsPIC33 (40MIPS)

PIC24F -- lower speed, more choices (16MIPS)
PIC24H -- faster (40MIPS)

They have a more modern core than PIC18. dsPICs have DSP instructions.
The C30 compiler is based on gcc.

--
Xiaofan http://mcuee.blogspot.com

2009\06\09@234129 by solarwind

picon face
On Wed, Jun 10, 2009 at 2:23 AM, Xiaofan Chen<RemoveMExiaofancTakeThisOuTspamgmail.com> wrote:
> For details you have to go to the Microchip website.
> http://www.microchip.com/16bit
>
> dsPIC30 -- old CMOS technology, 5V, high current consumption (30MIPS)
> dsPIC33 -- 3.3V, lower current consumption, faster than dsPIC33 (40MIPS)
>
> PIC24F -- lower speed, more choices (16MIPS)
> PIC24H -- faster (40MIPS)
>
> They have a more modern core than PIC18. dsPICs have DSP instructions.
> The C30 compiler is based on gcc.

Thanks! The thing is - I hate how the 16 bit MCUs are right in the
middle. 8 bit has been good enough for whatever I needed. If I wanted
more speed, flash, and RAM, I might as well go for the PIC32 since all
of the cool 16 bit chips are 3.3 V anyway...

How does power consumption compare for the 8 bit, 16 bit, and PIC32?

Also, the ARM920 is really cool since I can add external RAM and FLASH
as I please. Also, the MMU will come in handy to run QNX. Only problem
with this is the power consumption. How does the power consumption of
the ARM920s compare to the PIC MCUs?

For some of my home automation projects, I will need to solar power
the circuits (the ones outside) and use a large capacitor +
rechargeable battery to store the energy. I'd like to keep power
consumption to a minimum.

2009\06\10@003552 by Tamas Rudnai

face picon face
On Wed, Jun 10, 2009 at 2:23 AM, Xiaofan Chen <spamBeGonexiaofancspamBeGonespamgmail.com> wrote:

> dsPIC33 -- 3.3V, lower current consumption, faster than dsPIC33 (40MIPS)
>

I guess you wanted to say "faster than dsPIC30 (40MIPS)"

Tamas
--
http://www.mcuhobby.com

2009\06\10@010352 by Xiaofan Chen

face picon face
On Wed, Jun 10, 2009 at 11:41 AM, solarwind<TakeThisOuTx.solarwind.xEraseMEspamspam_OUTgmail.com> wrote:

> Thanks! The thing is - I hate how the 16 bit MCUs are right in the
> middle. 8 bit has been good enough for whatever I needed. If I wanted
> more speed, flash, and RAM, I might as well go for the PIC32 since all
> of the cool 16 bit chips are 3.3 V anyway...
>
> How does power consumption compare for the 8 bit, 16 bit, and PIC32?

The per MIPS current consumption should be similar.

> Also, the ARM920 is really cool since I can add external RAM and FLASH
> as I please. Also, the MMU will come in handy to run QNX. Only problem
> with this is the power consumption. How does the power consumption of
> the ARM920s compare to the PIC MCUs?

Per MIPS current consumption should be similar. But those ARM920 needs
external RAM and Flash so the system power consumption may be higher.

> For some of my home automation projects, I will need to solar power
> the circuits (the ones outside) and use a large capacitor +
> rechargeable battery to store the energy. I'd like to keep power
> consumption to a minimum.

As for Solar Power, they are still different from battery powered.
So current consumption situation may not be that bad.

Microchip has the nanoWatt XLP MCUs.
http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=1484

MSP430 is still hard to beat in terms of low current consumption
per MIPS.

--
Xiaofan http://mcuee.blogspot.com

2009\06\10@010413 by Xiaofan Chen

face picon face
On Wed, Jun 10, 2009 at 12:35 PM, Tamas Rudnai<RemoveMEtamas.rudnaispamTakeThisOuTgmail.com> wrote:
>> dsPIC33 -- 3.3V, lower current consumption, faster than dsPIC33 (40MIPS)
>>
> I guess you wanted to say "faster than dsPIC30 (40MIPS)"
>

You are right.



--
Xiaofan http://mcuee.blogspot.com

2009\06\10@065851 by cdb

flavicon
face


:: PIC24F -- lower speed, more choices (16MIPS)
:: PIC24H -- faster (40MIPS)

Don't forget, the 24 series don't have onchip EEPROM

Colin
--
cdb, colinEraseMEspam.....btech-online.co.uk on 10/06/2009

Web presence: http://www.btech-online.co.uk  

Hosted by:  http://www.1and1.co.uk/?k_id=7988359







2009\06\10@070759 by Xiaofan Chen

face picon face
On Wed, Jun 10, 2009 at 6:58 PM, cdb<EraseMEcolinspambtech-online.co.uk> wrote:
>
>
> :: PIC24F -- lower speed, more choices (16MIPS)
> :: PIC24H -- faster (40MIPS)
>
> Don't forget, the 24 series don't have onchip EEPROM
>

The PIC18J device Solarwind is looking at
do not have on-chip EEPROM either.


--
Xiaofan http://mcuee.blogspot.com

2009\06\10@074218 by olin piclist

face picon face
solarwind wrote:
> I should start using 16 bit controllers. What's the
> major differences between the 8 bit series and the 16 bit series?
> What's the power consumption like?

Just like the datasheet says it is.  What part were you confused by?


********************************************************************
Embed Inc, Littleton Massachusetts, http://www.embedinc.com/products
(978) 742-9014.  Gold level PIC consultants since 2000.

2009\06\10@074828 by olin piclist

face picon face
solarwind wrote:
> Thanks! The thing is - I hate how the 16 bit MCUs are right in the
> middle. 8 bit has been good enough for whatever I needed. If I wanted
> more speed, flash, and RAM, I might as well go for the PIC32 since all
> of the cool 16 bit chips are 3.3 V anyway...

There are plenty of dsPIC 30F that run on 5V.

> How does power consumption compare for the 8 bit, 16 bit, and PIC32?

RTFM!  This is directly and clearly answered in the manual right where you'd
expect to find it.


********************************************************************
Embed Inc, Littleton Massachusetts, http://www.embedinc.com/products
(978) 742-9014.  Gold level PIC consultants since 2000.

2009\06\11@170503 by Eoin Ross

flavicon
face
No - it's due to their support for recursion ;)

>>> Tamas Rudnai <RemoveMEtamas.rudnaiEraseMEspamEraseMEgmail.com> 10 Jun 09 00:35:47 >>>
On Wed, Jun 10, 2009 at 2:23 AM, Xiaofan Chen <RemoveMExiaofancspam_OUTspamKILLspamgmail.com> wrote:

> dsPIC33 -- 3.3V, lower current consumption, faster than dsPIC33 (40MIPS)
>

I guess you wanted to say "faster than dsPIC30 (40MIPS)"

Tamas


2009\06\11@213905 by solarwind

picon face
On Wed, Jun 10, 2009 at 2:23 AM, Xiaofan Chen<RemoveMExiaofancTakeThisOuTspamspamgmail.com> wrote:
> For details you have to go to the Microchip website.
> http://www.microchip.com/16bit
>
> dsPIC30 -- old CMOS technology, 5V, high current consumption (30MIPS)
> dsPIC33 -- 3.3V, lower current consumption, faster than dsPIC33 (40MIPS)
>
> PIC24F -- lower speed, more choices (16MIPS)
> PIC24H -- faster (40MIPS)
>
> They have a more modern core than PIC18. dsPICs have DSP instructions.
> The C30 compiler is based on gcc.

I'm looking at some cool DIP package parts in the 16 bit series.

This is what I've narrowed it down to:
http://img8.imageshack.us/img8/39/microchip.png

The 5v parts have less flash and RAM than my 18F2620 - so I'll just
stick with 3.3 V parts - I don't mind.

Also, I've googled for this, but can't find a satisfactory
explanation. What are DSP instructions?

2009\06\11@214718 by Vitaliy

flavicon
face
Olin Lathrop wrote:
>> How does power consumption compare for the 8 bit, 16 bit, and PIC32?
>
> RTFM!  This is directly and clearly answered in the manual right where
> you'd
> expect to find it.

Some datasheets do not specify operating current with PIC running at
different frequencies. There are many other factors that need to be taken
into account, as well.

Sometimes I ask such open-ended questions just to get a second opinion.
Although of course I try to remember to explain that I'm asking the question
not because I'm too lazy to look it up, but rather because I'm seeking
illuminating insights. :)

Vitaliy

2009\06\11@220929 by Xiaofan Chen

face picon face
On Fri, Jun 12, 2009 at 9:38 AM, solarwind<EraseMEx.solarwind.xspamspamspamBeGonegmail.com> wrote:
> Also, I've googled for this, but can't find a satisfactory
> explanation. What are DSP instructions?

Some simple introductions:
en.wikipedia.org/wiki/PIC_microcontroller
http://en.wikipedia.org/wiki/Digital_signal_processor

Some people classify dsPICs as DSCs.
en.wikipedia.org/wiki/Digital_Signal_Controller
"On the DSP side, they incorporate features found on most
DSPs such as single-cycle multiply-accumulate (MAC) units,
barrel shifters, and large accumulators."

This following sentence is apparently wrong.
"The term was first introduced by Microchip Technology in 2002
with the launch of their 6000 series DSCs and subsequently
adopted by most, but not all DSC vendors".



--
Xiaofan http://mcuee.blogspot.com

2009\06\12@080739 by olin piclist

face picon face
solarwind wrote:
> Also, I've googled for this, but can't find a satisfactory
> explanation. What are DSP instructions?

DSP stands for "digital signal processing".  This means at the very least
the the architecture is designed for fast repetivite multiply-accumulates.

It turns out that any linear filter can be realized with a convolution in
the time domain.  I know that probably sounds like gobbledygook at this
point.  The theory behind this is not immediately intuitive, and is usually
introduced in a second or third year college course on digital signal
processing.  This is where you learn that things like impulse response, step
response, fourier transform, convolution, and the frequency response of a
filter are all tightly related.  To make sense of this, you have to learn to
think of filters both in time domain and in frequency domain, and have a
good understanding how manipulations in one effect the other.  This is great
stuff to learn, but unfortunately is too much and too far ahead of where you
are now for me to try explaining it in a PIClist message.

To actually implement arbitrary linear filters digitally you need to perform
convolutions.  This is basically multiplying corresponding elements in two
arrays and adding up all the products.  In other words:

 output =
   signal[0] * kernel[0] +
   signal[1] * kernel[1] +
   signal[2] * kernel[2] +
   ...

Anything calling itself a DSP should be able to perform each line of the
equation above very quickly, usually in a single isntruction cycle.  That
not only means doing a multiply and adding the result into a accumulator,
but also updating the source addresses, possibly dealing with circular
buffers, and checking for loop termination.  It's OK for some of this to be
pipelined, but once things are going each additional multiply-accumulate
must take the minimum possible incremental time.


********************************************************************
Embed Inc, Littleton Massachusetts, http://www.embedinc.com/products
(978) 742-9014.  Gold level PIC consultants since 2000.

More... (looser matching)
- Last day of these posts
- In 2009 , 2010 only
- Today
- New search...