RAM chip

2022-04-27T11:38:23Z

Tandgnissle: /* Palette */

[[MVS hardware|MVS]] RAM chips often fry due to overvoltage from a badly adjusted or failing cab power supply. It appears that the most common failure mode is the inability to write new data, resulting in errors during [[system self-test]] at the beginning of address ranges.

NeoGeo use multiples SRAM (Static RAM) types:
* Work, Backup and lower Video RAM chips are 256k SRAM (5 volt, JEDEC pin compatible, 32K x 8bit) and only differ by speed. They have "256" or "257" in their markings
* Fast Video RAM (VRAM $8000~$87FF) chips are embedded into a Neo-GRC chip or 16k SRAM (5 volt, 24pin DIP, 2K x 8bit, 35ns or faster), however some [[MVS hardware|MVS]] and [[AES hardware|AES]] allow the use of a 28pin SRAM by the use of a jumper.
* Sound RAM chips are 16k SRAM (5 volt, 24pin DIP, 2K x 8bit, 150ns or faster) - fast Video RAM chip can be used as a replacement as they are faster (35ns).
* Palette RAM chips are 64k SRAM (5 volt, JEDEC pin compatible, 8K x 8bit, 120ns or faster)

See [[memory speed]] for details about speed grades.

==Pictures==

<gallery>
File:Cxk58256mm12.jpg|Sony CXK58256 120ns Work, Backup and Video RAM
File:CXK5864BSP-10L.jpg|Sony CXK5864BSP 100ns Palette RAM
File:CXK5814P-35L.jpg|Sony CXK5814P 35ns fast Video RAM
File:BR6216B-10LL.jpg|BR6216B 100ns Sound RAM
File:BR6265BF-10SL.jpg|BR6265BF 100ns Palette RAM
File:BR6216A-15L.jpg|BR6216A 150ns Sound RAM
</gallery>

==Pinout and cross-refence==

===Work, Backup, Video===
* CXK58256MM-12
* KM62256CLG-7
* W24258S-70LE
* CXK58257AM-12LX
* any "43256", "62256", CXK58257

===Fast Video===
* CXK5814P-35L
* CXK5863P-35L (only on boards that allow the use by changing the jumper)
* any CXK5814, CYC128A, 6116

===Palette===
* CXK5864BSP-10L
* LH5168N-80L
* XLJ6265AF-10SL
* BR6265BF-10SL
* "6164" for generic device test

===Sound===
* BR6116-100
* BR6216B-10LL
* BR6216A-10LL
* any CXK5814, CYC128A, 6116

==Replacement==

For '''Work, Backup and Video RAM''' look for 256kbit SRAM, 5 volt, JEDEC pin compatible, 32K x 8bit, 120ns or faster in 28 pin SOIC package (not SOJ).
Cypress, ISSI, UMC and Lyontek still make them and most today are 45ns, so any will do. This includes 62256, 43256, cxk58257, and others.

For '''fast Video RAM''' look for 16kbit SRAM, 5 volt, JEDEC pin compatible, 2K x 8bit, 35ns or faster in 24pin DIP package. 
For '''Sound RAM''' look for 16kbit SRAM, 5 volt, JEDEC pin compatible, 2K x 8bit, 150ns or faster in 24pin DIP package. 
This includes the CXK5814, CYC128A, and 6116 ICs, provided they are fast enough.

For '''Palette RAM''' chips
The can be replaced by 64k RAM chips off of old 386/486 motherboards (fast cache).
This includes the CXK5864BSP-10L 28 pin DIP and LH5168N-80L 28 pin SOIC

==Chips types and locations==

===MV-1===
* Work: CXK58256MM-12, G3 & H3
* Backup: CXK58256MM-12, H5 & H6
* Video: CXK58256MM-12, G4 & H4
* fast Video: CXK5814P-35L, C5 & D5
* Palette: CXK5864BSP-10L, H9 & H10
* Sound: BR6116-100, H1

===MV-1A===
* Work: KM62256CLG-7, RAM1 & RAM2
* Backup: KM62256CLG-7, RAM3 & RAM4
* Video: KM62256CLG-7, RAM5 & RAM6
* fast Video: none
* Palette: LH5168N-80L, BR6265BF-10SL, RAM7 & RAM8
* Sound: BR6216B-10LL, RAM9

===MV-1B===
* Work: KM62256CLG-7, RAM1 & RAM2
* Backup: KM62256CLG-7, RAM3 & RAM4
* Video: KM62256CLG-7, RAM5 & RAM6
* fast Video: none
* Palette: none
* Sound: BR6216B-10LL, RAM7

===MV-1C===
* Work: W24258S-70LE, RAM1 & RAM3
* Backup: W24258S-70LE, RAM2 & RAM4
* Video: W24258S-70LE, RAM5 & RAM6
* fast Video: none
* Palette: none
* Sound: none

===MV1FS===
* Work: CXK58257AM-12LX, H4 & H5
* Backup: CXK58257AM-12LX, H6 & H7
* Video: CXK58257AM-12LX, B4 & B5
* fast Video: CXK5814P-35L, C6 & D6
* Palette: CXK5864BSP-10, H8 & H8
* Sound: BR6116-10, K3

===MV1FZ & MV1FZS===
* Work: KM62256CLG-7, RAM1 & RAM2
* Backup: KM62256CLG-7, RAM3 & RAM4
* Video: KM62256CLG-7, RAM5 & RAM6
* fast Video: CXK5814P-35L, RAM7 &RAM8
* Palette: XLJ6265AF-10SL, RAM9 & RAM10
* Sound: BR6216B-10LL, RAM11

===MV2FS===
* Work: LH52B256N-70LL, D3 & D4
* Backup: LH52B256N-70LL, G1 & G2
* Video: LH52B256N-70LL, C7 & C8
* fast Video: CXK5814P-35L, C9 & D9
* Palette: CXK5864BSP-10L, B8 & B8
* Sound: BR6216B-10LL, K11

===MV2-01===
* Work: LH52B256N-70LL, E5 & E6
* Backup: LH52B256N-70LL, H3 & H4
* Video: LH52B256N-70LL, F13 & G13
* fast Video: CXK5814P-35L, F12 & G12
* Palette: CXK5864BSP-10L, B9 & C9
* Sound: BR6216B-10LL, BR6216A-10LL, K13

===MV-4F===
* Work: CXK58256MM-12L, G9 & H9
* Backup: CXK58256MM-12L, D9 & E9
* Video: CXK58256MM-12L, K9 & L9
* fast Video: CXK5814P-35L, L11 & M11
* Palette: CXK5864BSP-10L, F4 & H4
* Sound: BR6216B-10LL, L1

===MV-6===
* Work: H9 (lower) & J9 (upper)
* Backup: E9 (upper) & F9 (lower)
* Video: L9 & K9
* fast Video: CXK5814P-35L, M11 & N11
* Palette: CXK5864BSP-10L, G4 & H4
* Sound: BR6116-100, M1

[[Category:Chips]]
[[Category:Repairs]]

Power supply

2017-10-13T17:22:12Z

Tandgnissle:

Home consoles (AES) barrel jack polarity: '''outer is positive''', inner is ground. Note: early systems '''don't have reverse-polarity protection !'''

Also see [[power requirements]], for specific current requirements for each system.

=NEO-POW3=

Two versions, one reference...

* Input: 110V AC '''only'''
* Ouput: 10V DC 1A

...and...

* Input: 110V AC '''only'''
* Ouput: 11V DC 700mA

This one can fry early 5V systems.

==PRO-POW==

* Input: 100V AC '''only'''
*Output: 5V DC 3A

==PRO-POW-UL==

* Input: 120V AC '''only'''
* Output: 5V DC 3A

==PRO-POW-PAL==

* Input: 220V-240V AC '''only'''
* Output: 5V DC 3A

==POWCD-E==

* Input: 110V-240V AC (universal)
* Output 5V DC 2A, 10V DC 1A

==POWCD-J==

* Input: 100V AC '''only'''
* Output 5V DC 2A, 10V DC 1A

==POWCD-Y==

* Input: 110V-240V AC (universal)
* Output 5V DC 2A, 10V DC 1A

Maybe just a revision of POWCD-E.

[[Category:Base system]]

NeoGeo Development Wiki - User contributions [en]

RAM chip

Power supply