to gchapman: Are you on some sort of mailing list that you get announcements for all these new documents that you post? Is there some forum or web page at Microchip where they are announced?
(In any case, thank you for reposting them here, attached to relevant threads!)
Posted by gchapman: Fri. Feb 26, 2021 - 02:08 PM(Reply to #253)
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westfw wrote:
Are you on some sort of mailing list that you get announcements for all these new documents that you post?
No
westfw wrote:
Is there some forum or web page at Microchip where they are announced?
web pages
westfw wrote:
(In any case, thank you for reposting them here, attached to relevant threads!)
You're welcome!
P.S.
A foundry's application engineers, by significant effort and work, create application notes and source code that expands on what's in the data sheets (ideally created by design engineers)
Same application engineers may write trade journal articles though these journals aren't like the ones in the past (circa '10)
Same engineers attend conferences that are now virtual (where's the swag?)
(sucking sound from the drain)
Chin up!
How to search for Microchip PCNs (change control board releases data sheets, errata, assemble & test, wafer fab for new die or new fabs)
Updated the GitHub repository links, the References section, and the use cases sections. Added the AVR® DA Family Overview and Revision History sections. Added MCC versions for each use case, running on AVR128DA48. Other minor corrections.
Updated the GitHub repository links, the References section, and the use cases sections. Added the AVR® DA Family Overview and Revision History sections. Added MCC versions for each use case, running on AVR128DA48. Other minor corrections.
Updated the GitHub repository links, the References section, and the use cases sections. Added the AVR® DA Family Overview, Dithering Feature and Revision History sections. Added MCC versions for each use case, running on AVR128DA48. Other minor corrections.
I really don't understand what are DD and DE families for. All of them seem to be practically identical and no significant improvement since ATmega4809. I wish new AVRs have USB working as Virtual COM Port. This would be really nice to get rig o CP2102/FT230... old XMEGA AU serial have USB and this was really useful.
Posted by gchapman: Mon. Mar 15, 2021 - 07:01 PM(Reply to #257)
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Low pin count (growth from tinyAVR 0, 1, and 2-series)
extronic wrote:
... and no significant improvement since ATmega4809.
mega4809 has a single-ended ADC, no high frequency crystal oscillator, etc.; a mega4809 advantage is packaging (PDIP-40 vs PDIP-28)
extronic wrote:
I wish new AVRs have USB working as Virtual COM Port.
Concur; maybe AVR DC.
USB is a mid-complexity peripheral; some difficulty to be complete, precise, and correct with USB and squeeze the USB controller into the limited die space.
Maybe AVR Dx USB access will be by another means (USB megaAVR : dual-port RAM, USB XMEGA AVR : pseudo dual-port RAM and the four RMW instructions)
extronic wrote:
This would be really nice to get rig o CP2102/FT230
Yet there's innovation in USB UART :
crystal-less
very high baud
24MHz clock to the MCU
extronic wrote:
... old XMEGA AU serial have USB and this was really useful.
I looking forward to -DD because of the package size. 4mm QFN vs 5mm makes *a lot* of difference to me. Then I can drop SAMD11 which is too memory-constrained (although it does have USB, if you can afford the memory use).
Updated the GitHub repository links, the References section, and the use cases sections. Added the AVR® DA Family Overview and Revision History sections. Added MCC versions for each use case, running on AVR128DA48. Other minor corrections.
Updated the GitHub repository links, the References section, and the use cases sections. Added the AVR® DA Family Overview and Revision History sections. Added MCC versions for each use case, running on AVR128DA48. Other minor corrections.
Updated the GitHub repository links, the References section, the use cases sections, and the use cases figures. Added the AVR® DA Family Overview, Advanced Examples and Revision History sections. Added MCC versions for each use case, running on AVR128DA48. Other minor corrections.
There are so many monolithic buck converters, some which only require outboard capacitors. Don't see why one would build one oneself. You can control the voltage with a filtered PWM signal to bias the Feedback pin.
Posted by gchapman: Thu. Apr 1, 2021 - 05:26 PM(Reply to #262)
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glewis wrote:
Don't see why one would build one oneself.
voltage
digital control (in primary or secondary)
digital compensation (flexibility in matching load to source as either or both change impedance)
though current BCD processes and designs have transistors with significant drain-source max voltage; there are significant use cases for 40Vdc and greater (power tools, mowers, engine start-stop, hybrid EV, etc)
glewis wrote:
You can control the voltage with a filtered PWM signal to bias the Feedback pin.
or a DAC though DAC are more prevalent in follow-on AVR.
BCD - Bipolar-CMOS-DMOS (low noise analog front-end, control logic, power switches)
The presented solution creates a cost-effective motor driver by using an 8-bit microcontroller when traditionally, only 16-bit microcontrollers or more were used in creating this device.
The motor control board could drive the motor for some water well pumps; Plug-In Module (PIM) for AVR DA and AVR DB are forthcoming.
Posted by Svuppe: Sat. Aug 14, 2021 - 02:55 PM(Reply to #270)
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Coupon codes are nice, but can anyone actually buy anything from them?
I have been trying to buy the DB48 eval kit for the last hour, but I can't get past the checkout. It says there is something wrong with one or more fields in my address, but all is fine when I look. The address is the same as last time I ordered from Microchip Direct, and back then there was no problem.
Sigh. Emotionally, I really "want" an 8pin replacement for the ATtiny85. At least 8k of program space, DIP8/SOIC8 and cheaper than the t85. AVRxxDy8 or xTiny, I don't care.
(logically, I realize that many of the existing new chips already replace t85 WRT board space (in those tiny QFN packages, etc.), but it doesn't stop the "want.")
Sigh. Emotionally, I really "want" an 8pin replacement for the ATtiny85. At least 8k of program space, DIP8/SOIC8 and cheaper than the t85. AVRxxDy8 or xTiny, I don't care.
(logically, I realize that many of the existing new chips already replace t85 WRT board space (in those tiny QFN packages, etc.), but it doesn't stop the "want.")
I wonder if you could make a carrier PCB to meet that requirement.
Sigh. Emotionally, I really "want" an 8pin replacement for the ATtiny85. At least 8k of program space, DIP8/SOIC8 and cheaper than the t85. AVRxxDy8 or xTiny, I don't care.
(logically, I realize that many of the existing new chips already replace t85 WRT board space (in those tiny QFN packages, etc.), but it doesn't stop the "want.")
...
not and keep the “cheaper than a tiny85” part of the spec.
Those are rather dinosaur packages, with suppliers preferring to go for a split to smaller QFN packages, and gull wing packages like TSSOP14 to cover the customer needs.
( Whenever I've looked at 8 pin MCU's I've always come up a pin or two short. The MSOP10 I quite like, but that is also a bit niche. )
TSSOP20 is probably the highest volume 8 bit MCU gull-wing package these days.
ATTiny85 comes in wide 8-SOIC (0.209", 5.30mm Width), itself a bit unusual. Digikey says $1.07/1k
Looking at other vendors SO8 parts, I see
STM8S001 is 40c/1k for 8kF
and the new
IS31CS8975-GRLS2-TR is $0.68/1k for 1KB SRAM AND 16KF ECC 32MHz A/D 4x11b SAR; D/A 1x8b 8-SOIC (0.154", 3.90mm Width)
also comes in 16-TSSOP (0.173", 4.40mm Width) $0.74/1k, which is better value per IO pin.
In MSOP10 there are (this vendor skips SO8 packages)
Posted by bigmessowires: Fri. Dec 17, 2021 - 02:30 AM
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Has anyone experimented with overclocking an AVR-Dx? https://github.com/SpenceKonde/D... mentions that while the max rated speed is officially 24 MHz, speeds up to 32 MHz are "an overclock that is likely to work on all parts as long as it is run at room temperature" and even 40 MHz should work on "most parts" if you're making a one-off project. Somewhere else, I saw speculation that AVR-Dx was originally conceived as a 32 MHz part, but it couldn't quite meet that across its entire temperature and voltage range, so the official max speed was reduced.
I'm curious if anyone else has played with this, and which peripherals or behaviors tend to fail first when overclocked.
I'm curious if anyone else has played with this, and which peripherals or behaviors tend to fail first when overclocked.
I've OC to 28MHz out of curiosity and the peripherals I was using, TCA and TCB, were working seemingly ok at 5V. But of course OC an AVR is a bit pointless, if you really need speed there are plenty of choices (ARM MCUs for example).
Posted by bigmessowires: Fri. Dec 17, 2021 - 05:12 PM
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Thanks, I'm really interested in hearing any hands-on experience with overclocking the AVR-Dx series to 28 or 32 MHz. Sure, in an ideal world this would never be necessary, and I would just use a 120 MHz ARM or something, but it's helpful to have first-hand info about how AVR-Dx behaves above 24 MHz. If that DxCore document is reliable, 32 MHz is readily achievable under favorable voltage and temperature conditions.
Why? I'm revising an ATMEGA1284 design due to lack of available parts. AVR128DB makes the existing code easy to port, which is the most important factor to me. It's actually available right now in decent volumes, unlike so many other MCUs. 24 MHz operation will work to duplicate the existing design's capabilities, but 28 or 32 MHz would help it work even better under certain situations where it sometimes struggles now. So I'm considering an optional overclock setting. It wouldn't need to work 100 percent of the time, but it would be extra gravy if it does work most of the time.
Posted by gchapman: Fri. Dec 17, 2021 - 06:38 PM(Reply to #295)
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bigmessowires wrote:
I'm revising an ATMEGA1284 design due to lack of available parts.
52 week lead-time (Tempe's on though there's a lead frame shortage); PDIP stocked.
bigmessowires wrote:
AVR128DB makes the existing code easy to port, which is the most important factor to me.
Large difference in input/output between AVRe+ and AVRxt.
bigmessowires wrote:
So I'm considering an optional overclock setting. It wouldn't need to work 100 percent of the time, but it would be extra gravy if it does work most of the time.
CPU and SRAM likely can be overclocked.
NVM controller is iffy; flash read might be OK though definitely will have an upper limit.
I/O : some peripherals are uncertain (test)
3V VDD may be more reliable than 5V (AVR Dx : increased SOA versus megaAVR, CMOS has more than enough noise immunity, CMOS : power is proportional to the square of VDD)
Recommend an external watchdog; if concerned about latch-up then external watchdog power cycles VDD.
I have a board with a 25MHz clock available (at 3.3V) because of an ethernet onboard. Thinking of overclocking an AVRxxxDx at 3.3V too, with the external 25MHz wave.
Real life temperature corners are 0C...50C, lets say -10C...60C.
The main question in OC is whether flash access will work or not. But I doubt it will not work at 25MHz given it will at 24MHz :-)
Still, I'm not very comfortable getting out of specs...
Posted by bigmessowires: Sun. Dec 19, 2021 - 01:13 AM
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I asked SpenceKonde (the DxCore guy) about his overclocking tests. He said they were all run with a supply voltage close to 5V. But he believes that the supply voltage doesn't really matter, because the Dx AVRs have an internal voltage regulator for the core, so the core will run at the same voltage no matter what the supply voltage is. He said he runs at 32 MHz very often, and has neopixel controllers with LCD screens for UI that run at 40 MHz. In his experience, when increasing the overclock, the ALU fails first. So that's a very bullish overclocking report.
Do what you will with this information... personally I don't think I'd build a commercial product that requires running beyond the datasheet's maximum clock speed spec. There are some AVR projects that do this, though, based on ATMEGA chips. Two I can think of are JeeNode and Uzebox. But as an optional feature, I find the idea of a 32 MHz Dx pretty interesting and exciting. I'll definitely be experimenting with this more.
Keep in mind that the data sheet numbers are in place to meet each and every condition listed on it. A given system will only care for a subset of these conditions.
Overcurrent Protection Using the Integrated Op Amps on AVR® DB (web doc)
AN3860 Overcurrent Protection Using the Integrated Op Amps on AVR DB (PDF)
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Topto gchapman: Are you on some sort of mailing list that you get announcements for all these new documents that you post? Is there some forum or web page at Microchip where they are announced?
(In any case, thank you for reposting them here, attached to relevant threads!)
- Log in or register to post comments
TopP.S.
A foundry's application engineers, by significant effort and work, create application notes and source code that expands on what's in the data sheets (ideally created by design engineers)
Same application engineers may write trade journal articles though these journals aren't like the ones in the past (circa '10)
Same engineers attend conferences that are now virtual (where's the swag?)
(sucking sound from the drain)
Chin up!
How to search for Microchip PCNs (change control board releases data sheets, errata, assemble & test, wafer fab for new die or new fabs)
TechDoc (PDF are the reference)
Online Docs (web docs, subset of TechDoc)
RSS Feeds | Microchip Technology (RSS's typical use case is feeds to journalists)
What's New? - Developer Help
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TopTB3215 Getting Started with SPI (PDF)
TB3214 Getting Started with TCB (PDF)
edit :
"Dare to be naïve." - Buckminster Fuller
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TopAVR® Instruction Set Manual (PDF)
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TopI really don't understand what are DD and DE families for. All of them seem to be practically identical and no significant improvement since ATmega4809. I wish new AVRs have USB working as Virtual COM Port. This would be really nice to get rig o CP2102/FT230... old XMEGA AU serial have USB and this was really useful.
extronic.pl
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TopLow pin count (growth from tinyAVR 0, 1, and 2-series)
USB is a mid-complexity peripheral; some difficulty to be complete, precise, and correct with USB and squeeze the USB controller into the limited die space.
Maybe AVR Dx USB access will be by another means (USB megaAVR : dual-port RAM, USB XMEGA AVR : pseudo dual-port RAM and the four RMW instructions)
Features | ADC | ATmega4808/4809 Data Sheet
NEW! USB to UART G Series Archives | Prolific USA | IC Design & Manufacturing
XR21x14x Universal Async Receiver Transmitters - MaxLinear | Mouser due to CH340G IC vendor..... | AVR Freaks
USBXpress USB Bridges - USB-to-UART bridge controllers - Silicon Labs and Pololu - CP2102N USB-to-Serial Adapter Carrier
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TopI looking forward to -DD because of the package size. 4mm QFN vs 5mm makes *a lot* of difference to me. Then I can drop SAMD11 which is too memory-constrained (although it does have USB, if you can afford the memory use).
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TopGetting Started with Analog-to-Digital Converter (ADC) (PDF)
Getting Started with Digital-to-Analog Converter (DAC) (PDF)
edit :
TB3218 Getting started with CCL
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Top"Dare to be naïve." - Buckminster Fuller
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TopThere are so many monolithic buck converters, some which only require outboard capacitors. Don't see why one would build one oneself. You can control the voltage with a filtered PWM signal to bias the Feedback pin.
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Topthough current BCD processes and designs have transistors with significant drain-source max voltage; there are significant use cases for 40Vdc and greater (power tools, mowers, engine start-stop, hybrid EV, etc)
BCD - Bipolar-CMOS-DMOS (low noise analog front-end, control logic, power switches)
Hysteretic control though very low price :
84Vdc :
Electric propulsion system for PPG and Ultralights | AVR Freaks
Secondary control, digital control :
MCP1012 - AC/DC - Auxiliary Controllers
Schematic | AVR128DB48 Curiosity Nano Hardware User Guide (second sheet, A2)
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TopOne of the main reasons to switch the power with a micro is to be in sync with the switching noise.
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TopAVR64EA48 - 8-bit Microcontrollers
AVR64EA32 - 8-bit Microcontrollers
AVR64EA28 - 8-bit Microcontrollers
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TopThe motor control board could drive the motor for some water well pumps; Plug-In Module (PIM) for AVR DA and AVR DB are forthcoming.
edit : web doc
Sensorless BLDC Motor Control for AVR® Microcontrollersedit2 : 16 bit
Microchip's dsPIC33CK Low Voltage Motor Control (LVMC) Development Board - YouTube (6m6s)
edit3 :
AN3998 - Sensorless BLDC Motor Control for AVR® Microcontrollers
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Topplaylist :
AVR® DB | Hands-on Training - YouTube
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TopAN3860 Overcurrent Protection Using the Integrated Op Amps on AVR DB (PDF)
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Topon sale this month
Part Number: EV35L43A - AVR128DB48 Curiosity Nano Evaluation kit | Welcome to Microchip Technology | Microchip Technology Inc.
via Dev Tool Deals | Microchip Technology
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TopAugust Development Tools sale
via e-mail
AVR128DB48 CURIOSITY NANO EVALUATION KIT | Microchip Technology
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TopCoupon codes are nice, but can anyone actually buy anything from them?
I have been trying to buy the DB48 eval kit for the last hour, but I can't get past the checkout. It says there is something wrong with one or more fields in my address, but all is fine when I look. The address is the same as last time I ordered from Microchip Direct, and back then there was no problem.
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TopWeb sites are updated and have several applications that must communicate else fubar.
Try during business hours or try
Contact Us | World's Largest Inventory of Microchip Products
though there's a Denmark office.
FUBAR - Wiktionary
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Topversion 1.1 released 23-Aug'21
ISO 26262 Functional Safety Packages for AVR® DA
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TopAdditions are AVR Dx and Seiko Instruments crystals.
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Top"Dare to be naïve." - Buckminster Fuller
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TopUpdated and additional errata
AVR32DA Silicon Errata and Data Sheet Clarification
AVR64DA Silicon Errata and Data Sheet Clarification
AVR128DA Silicon Errata and Data Sheet Clarification
web doc
AVR32DA Silicon Errata and Data Sheet Clarification
AVR64DA Silicon Errata and Data Sheet Clarification
AVR128DA Silicon Errata and Data Sheet Clarification
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TopPublished yesterday; revision adds TWI driver note for AVR DA and AVR DB.
Supported Families | MPLAB® Code Configurator - Melody CryptoAuthentication Library Release Notes (CryptoAuthLib)
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TopAVR64DD32/28 Preliminary Data Sheet
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TopSigh. Emotionally, I really "want" an 8pin replacement for the ATtiny85. At least 8k of program space, DIP8/SOIC8 and cheaper than the t85. AVRxxDy8 or xTiny, I don't care.
(logically, I realize that many of the existing new chips already replace t85 WRT board space (in those tiny QFN packages, etc.), but it doesn't stop the "want.")
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TopI wonder if you could make a carrier PCB to meet that requirement.
I'd like to see USB.
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TopBetter a wireless interface.
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Topnot and keep the “cheaper than a tiny85” part of the spec.
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Top"Dare to be naïve." - Buckminster Fuller
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TopThose are rather dinosaur packages, with suppliers preferring to go for a split to smaller QFN packages, and gull wing packages like TSSOP14 to cover the customer needs.
( Whenever I've looked at 8 pin MCU's I've always come up a pin or two short. The MSOP10 I quite like, but that is also a bit niche. )
TSSOP20 is probably the highest volume 8 bit MCU gull-wing package these days.
ATTiny85 comes in wide 8-SOIC (0.209", 5.30mm Width), itself a bit unusual. Digikey says $1.07/1k
Looking at other vendors SO8 parts, I see
STM8S001 is 40c/1k for 8kF
and the new
IS31CS8975-GRLS2-TR is $0.68/1k for 1KB SRAM AND 16KF ECC 32MHz A/D 4x11b SAR; D/A 1x8b 8-SOIC (0.154", 3.90mm Width)
also comes in 16-TSSOP (0.173", 4.40mm Width) $0.74/1k, which is better value per IO pin.
In MSOP10 there are (this vendor skips SO8 packages)
MS51BA9AE $0.39/1k 8KB FLASH 1K RAM 24MHz I²C, SPI, UART/USART 2.4V ~ 5.5V A/D 4x12b -40°C ~ 105°C 10-MSOP (0.118", 3.00mm Width)
ML51BB9AE $0.54/1k 16KB FLASH 1K RAM 24MHz I²C, SPI, UART/USART 1.8V ~ 5.5V A/D 2x12b -40°C ~ 105°C 10-MSOP (0.118", 3.00mm Width)
and in TSSOP20 parts like
EFM8BB52F16G-C-TSSOP20 $0.47/1k 50MHz 16KB FLASH 1.25K RAM 1.8V ~ 5.5V A/D 16x12b D/A 1x10b -40°C ~ 85°C 20-TSSOP (0.173", 4.40mm Width)
EFM8BB52F32G-C-TSSOP20 $0.55/1k 50MHz 32KB FLASH 2.25K RAM 1.8V ~ 5.5V A/D 16x12b D/A 1x10b -40°C ~ 85°C 20-TSSOP (0.173", 4.40mm Width)
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TopSP3T-50x50-G | SMTpads, Size 3, 50x50mil | BusBoard Prototype Systems
Underfill revisited: How a decades-old technique enables smaller, more durable PCBs - Embedded.com
ATMEL parts are running out of stock due to wafer shortage ? | AVR Freaks
ATiny Liberation!... Self Replicating Boot Unloader. | AVR Freaks
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TopMy pseudo DIP8 has up to 32KB of flash.
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Topmore web pages for future AVR DD
avr32dd32 | Microchip Technology
AVR32DD28 | Microchip Technology
AVR32DD20 | Microchip Technology
AVR32DD14 | Microchip Technology
AVR16DD32 | Microchip Technology
AVR16DD28 | Microchip Technology
AVR16DD20 | Microchip Technology
AVR16DD14 | Microchip Technology
edit :
AVR64DD20 | Microchip Technology
AVR64DD14 | Microchip Technology
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Top"Dare to be naïve." - Buckminster Fuller
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TopHas anyone experimented with overclocking an AVR-Dx? https://github.com/SpenceKonde/D... mentions that while the max rated speed is officially 24 MHz, speeds up to 32 MHz are "an overclock that is likely to work on all parts as long as it is run at room temperature" and even 40 MHz should work on "most parts" if you're making a one-off project. Somewhere else, I saw speculation that AVR-Dx was originally conceived as a 32 MHz part, but it couldn't quite meet that across its entire temperature and voltage range, so the official max speed was reduced.
I'm curious if anyone else has played with this, and which peripherals or behaviors tend to fail first when overclocked.
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TopWhat a horrible set of graphs, all mismatched "axis" and scales... (better than nothing, of course!)
Hmm....

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TopThis is not for serious projects. In the vast majority of cases, frequencies below 10 mhz are really sufficient...
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TopI've OC to 28MHz out of curiosity and the peripherals I was using, TCA and TCB, were working seemingly ok at 5V. But of course OC an AVR is a bit pointless, if you really need speed there are plenty of choices (ARM MCUs for example).
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TopXMega cranks out NTSC color and digital stereo sound! | AVR Freaks
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TopFF = PI > S.E.T
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TopThanks, I'm really interested in hearing any hands-on experience with overclocking the AVR-Dx series to 28 or 32 MHz. Sure, in an ideal world this would never be necessary, and I would just use a 120 MHz ARM or something, but it's helpful to have first-hand info about how AVR-Dx behaves above 24 MHz. If that DxCore document is reliable, 32 MHz is readily achievable under favorable voltage and temperature conditions.
Why? I'm revising an ATMEGA1284 design due to lack of available parts. AVR128DB makes the existing code easy to port, which is the most important factor to me. It's actually available right now in decent volumes, unlike so many other MCUs. 24 MHz operation will work to duplicate the existing design's capabilities, but 28 or 32 MHz would help it work even better under certain situations where it sometimes struggles now. So I'm considering an optional overclock setting. It wouldn't need to work 100 percent of the time, but it would be extra gravy if it does work most of the time.
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TopNVM controller is iffy; flash read might be OK though definitely will have an upper limit.
I/O : some peripherals are uncertain (test)
3V VDD may be more reliable than 5V (AVR Dx : increased SOA versus megaAVR, CMOS has more than enough noise immunity, CMOS : power is proportional to the square of VDD)
Recommend an external watchdog; if concerned about latch-up then external watchdog power cycles VDD.
Lead Time | World's Largest Inventory of Microchip Products
Tempe Fab 2, Gresham Fab 4 | AVR Freaks
ATMEL parts are running out of stock due to wafer shortage ? | AVR Freaks
GPIO Basic Functionality | Migration from the megaAVR® to AVR® Dx Microcontroller Families
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TopI have a board with a 25MHz clock available (at 3.3V) because of an ethernet onboard. Thinking of overclocking an AVRxxxDx at 3.3V too, with the external 25MHz wave.
Real life temperature corners are 0C...50C, lets say -10C...60C.
The main question in OC is whether flash access will work or not. But I doubt it will not work at 25MHz given it will at 24MHz :-)
Still, I'm not very comfortable getting out of specs...
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TopEETimes - Go beyond the datasheet - Part 1: Dependencies and guardbands
edit :
Push Performance and Power Beyond the Data Sheet White Paper (Texas Instruments)
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TopI asked SpenceKonde (the DxCore guy) about his overclocking tests. He said they were all run with a supply voltage close to 5V. But he believes that the supply voltage doesn't really matter, because the Dx AVRs have an internal voltage regulator for the core, so the core will run at the same voltage no matter what the supply voltage is. He said he runs at 32 MHz very often, and has neopixel controllers with LCD screens for UI that run at 40 MHz. In his experience, when increasing the overclock, the ALU fails first. So that's a very bullish overclocking report.
Do what you will with this information... personally I don't think I'd build a commercial product that requires running beyond the datasheet's maximum clock speed spec. There are some AVR projects that do this, though, based on ATMEGA chips. Two I can think of are JeeNode and Uzebox. But as an optional feature, I find the idea of a 32 MHz Dx pretty interesting and exciting. I'll definitely be experimenting with this more.
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