Alliancememory

Example Decoding

AS6C4008-55PCN
|  |   |  ||||
|  |   |  |||+-- N = Lead-free (RoHS compliant)
|  |   |  ||+--- C = Commercial temperature (0 to +70C)
|  |   |  |+---- P = PDIP package
|  |   |  +----- 55 = 55ns access time
|  |   +-------- 4008 = 4Mbit density (512K x 8)
|  +------------ 6C = Async SRAM series
+--------------- AS = Alliance Memory prefix

AS4C256M16D3A-12BCN
|  |     | |||  ||||
|  |     | |||  |||+-- N = Lead-free
|  |     | |||  ||+--- C = Commercial temperature
|  |     | |||  |+---- B = BGA package
|  |     | |||  +----- 12 = 12ns (CL=11 DDR3)
|  |     | ||+-------- A = Revision A
|  |     | |+--------- D3 = DDR3 generation
|  |     | +---------- 16 = 16-bit data bus width
|  |     +------------ M = Mega (x1,000,000)
|  +------------------ 256 = 256 Megabits depth
+---------------------- AS4C = SDRAM/DDR series

Package Codes

Memory Package Mapping

Package Selection by Memory Type

Series Reference

AS6C - Asynchronous SRAM

Low-power async SRAM for embedded systems, battery-backed applications.

AS7C - High-Speed SRAM

Synchronous and high-speed async SRAM for performance applications.

AS4C - SDRAM and DDR SDRAM

AS29LV - NOR Flash

Legacy-compatible NOR Flash memory.

Temperature Grades

Speed Grades

Speed grade represents the access time in nanoseconds. Lower = faster.

SRAM Speed Grades

DDR Speed Grades

Flash Speed Grades

Handler Implementation Notes

Package Code Extraction

// Package code is after the speed grade digits
// AS6C4008-55PCN -> skip "55" (digits), first letter 'P' = PDIP

int hyphenIndex = mpn.indexOf('-');
String suffix = mpn.substring(hyphenIndex + 1);

// Skip speed grade digits
int i = 0;
while (i < suffix.length() && Character.isDigit(suffix.charAt(i))) {
    i++;
}
// suffix.charAt(i) is the package code

Series Extraction

// Extract the series prefix (before density digits)
if (mpn.startsWith("AS29LV")) return "AS29LV";  // Check longest first!
if (mpn.startsWith("AS6C")) return "AS6C";
if (mpn.startsWith("AS7C")) return "AS7C";
if (mpn.startsWith("AS4C")) return "AS4C";

IMPORTANT: Check "AS29LV" before the shorter prefixes - pattern order matters!

Density Extraction

// Different format for different series:
// AS6C/AS7C: numeric density after 4-char prefix
//   AS6C4008 -> "4008"
//   AS6C62256 -> "62256"

// AS4C: depth + "M" + width format
//   AS4C4M16SA -> "4M16" (4M x 16)
//   AS4C256M16D3A -> "256M16" (256M x 16)

// AS29LV: numeric density in Mbit (divide by 10 for actual)
//   AS29LV160B -> "160" (16Mbit)

Replacement Logic

The handler implements isOfficialReplacement() with these rules:

1. Same series required: AS6C cannot replace AS7C
2. Same density required: Different densities are not compatible
3. Faster can replace slower: 45ns can replace 55ns (not vice versa)
4. Wider temp can replace narrower: Industrial can replace Commercial
5. Package is flexible: Different packages are replaceable (design consideration)

Component Types

The handler supports:

Note: AS29LV matches BOTH MEMORY and MEMORY_FLASH types.

Cross-Reference with Other Manufacturers

Alliance Memory specializes in drop-in replacements:

Related Files

• Handler: manufacturers/AllianceMemoryHandler.java
• Tests: handlers/AllianceMemoryHandlerTest.java
• Component types: MEMORY, MEMORY_FLASH
• Similar handlers: MicronHandler, ISSIHandler, WinbondHandler

Learnings & Edge Cases

• Series prefix order: When matching, always check "AS29LV" (6 chars) before "AS6C" (4 chars) - otherwise AS29LV won't match correctly
• Density format varies by series: AS6C/AS7C use simple numbers (4008), AS4C uses "depth M width" format (256M16)
• DDR generation from suffix: D1=DDR1, D2=DDR2, D3=DDR3, SA=SDRAM
• Flash dual-type matching: AS29LV parts match both MEMORY and MEMORY_FLASH - this is intentional
• Low power variants: Some parts have 'L' in the part number (AS6C4008L) for low-power versions
• Revision letters: A/B after the base number indicates silicon revision (AS7C1024A, AS29LV160B)
• Lead-free indicator: 'N' suffix indicates RoHS-compliant lead-free packaging
• Temperature in suffix position: Temperature grade comes after package code, before lead-free indicator (55PCN = P-package, C-temp, N-lead-free)
• Handler uses Set.of(): Correctly uses immutable Set.of() in getSupportedTypes()
• Case-insensitive matching: Handler converts MPNs to uppercase before pattern matching