Atmel (now Microchip) Manufacturer Skill

MPN Structure

Atmel MPNs follow this general structure:

[FAMILY][SERIES][VARIANT]-[PACKAGE][TEMP]
   │       │        │         │      │
   │       │        │         │      └── Optional temperature grade
   │       │        │         └── Package code (after hyphen)
   │       │        └── Feature variant (P=picopower, A=automotive, etc.)
   │       └── Series number (flash size, pin count encoded)
   └── Product family (ATMEGA, ATTINY, ATSAM, etc.)

Example Decoding

ATMEGA328P-PU
│     │  │  ││
│     │  │  │└── (no temp suffix = commercial)
│     │  │  └── U in PU = standard grade
│     │  └── P = picoPower technology
│     └── 328 = 32KB flash, 8-bit
└── ATMEGA = AVR 8-bit megaAVR family

ATSAM3X8E-AU
│    │ ││  ││
│    │ ││  │└── U = standard grade
│    │ ││  └── A = TQFP package
│    │ │└── E = Ethernet variant
│    │ └── 8 = 512KB flash
│    └── 3X = Cortex-M3 SAM3X series
└── ATSAM = ARM-based SAM family

---

Package Codes (After Hyphen)

Code	Package	Description
PU	PDIP	Plastic Dual In-line Package (through-hole)
AU	TQFP	Thin Quad Flat Pack (surface mount)
MU	QFN/MLF	Quad Flat No-leads / Micro Lead Frame
SU	SOIC	Small Outline IC
XU	TSSOP	Thin Shrink Small Outline Package
TU	QFP	Quad Flat Pack (larger than TQFP)
CU	WLCSP/UCSP	Wafer Level / Ultra Chip Scale Package
SS	SSOP	Shrink Small Outline Package

Package Code Pattern

[PACKAGE_TYPE][GRADE]
      │          │
      │          └── U = Standard, C = Commercial, I = Industrial
      └── P=PDIP, A=TQFP, M=QFN, S=SOIC, X=TSSOP, T=QFP, C=WLCSP

---

Product Families

8-bit AVR Microcontrollers

Family	Description	Example
ATmega	Feature-rich 8-bit	ATMEGA328P, ATMEGA2560
ATtiny	Small footprint 8-bit	ATTINY85, ATTINY13A
AT90	USB/CAN enabled	AT90USB162, AT90CAN128
ATxmega	Extended 8/16-bit	ATXMEGA128A1U

32-bit ARM Microcontrollers

Family	Core	Example
ATSAM3	Cortex-M3	ATSAM3X8E (Arduino Due)
ATSAM4	Cortex-M4	ATSAM4S16B
ATSAMD	Cortex-M0+	ATSAMD21G18A
ATSAME	Cortex-M7	ATSAME70Q21

Memory Products

Family	Type	Example
AT24C	I2C EEPROM	AT24C256-PU (256Kbit)
AT25	SPI EEPROM/Flash	AT25SF041 (4Mbit Flash)
AT45DB	DataFlash	AT45DB321E

Security/Touch Products

Family	Type	Example
ATECC	Crypto Authentication	ATECC608A
ATSHA	SHA Authentication	ATSHA204A
AT42QT	QTouch Controller	AT42QT1010
ATMXT	maXTouch Controller	ATMXT336S

---

Series Number Encoding

ATmega Series Numbers

The number encodes flash size and sometimes pin count:

Series	Flash	SRAM	EEPROM	Notes
ATMEGA8	8KB	1KB	512B	Original
ATMEGA88	8KB	1KB	512B	Improved
ATMEGA168	16KB	1KB	512B	Pin-compatible with 88
ATMEGA328	32KB	2KB	1KB	Arduino Uno
ATMEGA1284	128KB	16KB	4KB	High memory
ATMEGA2560	256KB	8KB	4KB	Arduino Mega

ATtiny Series Numbers

Series	Flash	Pins	Notes
ATTINY13	1KB	8	Smallest
ATTINY25	2KB	8
ATTINY45	4KB	8
ATTINY85	8KB	8	Popular small MCU
ATTINY84	8KB	14	More I/O
ATTINY2313	2KB	20	UART included

---

Variant Suffixes (Before Hyphen)

Suffix	Meaning
P	picoPower - Ultra low power modes
A	Revision A / Automotive grade
V	Low voltage operation (1.8V-5.5V)
PA	picoPower + Automotive
PB	picoPower revision B
U	USB capable
L	Low voltage (1.8V-3.6V only)

Example Variants

ATMEGA328    → Original
ATMEGA328P   → picoPower (lower sleep current)
ATMEGA328PB  → picoPower revision B (more features)
ATMEGA328PA  → Automotive grade picoPower

---

Temperature Grades

Grade	Range	Suffix Position
Commercial	0°C to +70°C	(no suffix)
Industrial	-40°C to +85°C	Often implicit
Automotive	-40°C to +125°C	A in variant or separate

---

Common Arduino Mappings

Arduino Board	MCU	Full MPN
Uno	ATmega328P	ATMEGA328P-PU
Nano	ATmega328P	ATMEGA328P-AU
Mega 2560	ATmega2560	ATMEGA2560-16AU
Leonardo	ATmega32U4	ATMEGA32U4-AU
Due	ATSAM3X8E	ATSAM3X8E-AU
Zero	ATSAMD21G18A	ATSAMD21G18A-AU

---

Handler Implementation Notes

Package Code Extraction

// Atmel package codes are AFTER the hyphen
// ATMEGA328P-PU → package = "PU"

String[] parts = mpn.split("-");
if (parts.length > 1) {
    String suffix = parts[parts.length - 1];
    return switch (suffix) {
        case "PU" -> "PDIP";
        case "AU" -> "TQFP";
        case "MU" -> "QFN/MLF";
        case "SU" -> "SOIC";
        case "XU" -> "TSSOP";
        case "TU" -> "QFP";
        case "CU" -> "WLCSP";
        default -> suffix;
    };
}

Series Extraction

// Extract family + number, stop at variant letter or hyphen
// ATMEGA328P-PU → series = "ATMEGA328"
// ATTINY85-20PU → series = "ATTINY85"

if (mpn.startsWith("ATMEGA")) {
    // Find end of digits after "ATMEGA"
    int end = "ATMEGA".length();
    while (end < mpn.length() && Character.isDigit(mpn.charAt(end))) {
        end++;
    }
    return mpn.substring(0, end);
}

Pattern Matching

// ATmega: ATMEGA + digits + optional letter variant + optional -package
"^ATMEGA[0-9]+[A-Z]?(?:-[A-Z]{2,4})?$"

// ATtiny: ATTINY + digits + optional variant + optional -package
"^ATTINY[0-9]+[A-Z]?(?:-[A-Z]{2,4})?$"

// SAM: ATSAM + series + variant + -package
"^ATSAM[A-Z0-9]+(?:-[A-Z]{2,4})?$"

---

Pin Compatibility Groups

28-pin PDIP/TQFP Compatible

• ATMEGA8 / ATMEGA88 / ATMEGA168 / ATMEGA328
• Direct drop-in replacements (different flash sizes)

8-pin DIP/SOIC Compatible

• ATTINY13 / ATTINY25 / ATTINY45 / ATTINY85
• Increasing flash sizes, same pinout

44-pin TQFP Compatible

• ATMEGA16 / ATMEGA32 / ATMEGA644 / ATMEGA1284

---

Related Files

• Handler:

  manufacturers/AtmelHandler.java

• Component types:

  MICROCONTROLLER_ATMEL

  ,

  MCU_ATMEL

  ,

  MEMORY_ATMEL

  ,

  TOUCH_ATMEL

  ,

  CRYPTO_ATMEL

• Package registry:

  PackageCodeRegistry.java

  (Atmel-specific codes: PU, AU, MU, SU, XU, CU)

---

Learnings & Edge Cases

• Microchip acquisition: Atmel was acquired by Microchip in 2016. New parts may have Microchip branding but same MPN structure
• Speed grades: Some parts have speed suffix before package (e.g., ATMEGA328P-20AU = 20MHz max)
• PU vs AU: Same chip, different package. PU=DIP for prototyping, AU=TQFP for production
• P suffix importance: ATMEGA328 and ATMEGA328P are different! The P version has lower power consumption
• Memory in name: ATmega328 has 32KB flash (32), ATtiny85 has 8KB (8), but encoding isn't always consistent

Handler Cleanup Notes (TODO)

AtmelHandler needs the same cleanup as TIHandler (PR #77):

• Replace

  HashSet

  with

  Set.of()

  in

  getSupportedTypes()

• Handler doesn't use

  PackageCodeRegistry

  - has local switch statement
• Pattern may not handle speed grades like

  -20AU

  (20MHz before package)
• Case sensitivity - some methods use

  mpn.startsWith()

  without

  toUpperCase()

Test Notes

When creating AtmelHandlerTest:

• Put in

  no.cantara.electronic.component.lib.handlers

  package (NOT

  manufacturers

  )
• Use

  @BeforeAll

  with

  MPNUtils.getManufacturerHandler("ATMEGA328P")

• Test categories: ATmega, ATtiny, AT90, XMEGA, SAM, Memory (AT24C, AT25), Touch (AT42QT), Crypto (ATECC, ATSHA)

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