Bekijk alles

Raadpleeg de Engelse versie als onze officiële versie.Opbrengst

Europa
France(Français) Germany(Deutsch) Italy(Italia) Russian(русский) Poland(polski) Czech(Čeština) Luxembourg(Lëtzebuergesch) Netherlands(Nederland) Iceland(íslenska) Hungarian(Magyarország) Spain(español) Portugal(Português) Turkey(Türk dili) Bulgaria(Български език) Ukraine(Україна) Greece(Ελλάδα) Israel(עִבְרִית) Sweden(Svenska) Finland(Svenska) Finland(Suomi) Romania(românesc) Moldova(românesc) Slovakia(Slovenská) Denmark(Dansk) Slovenia(Slovenija) Slovenia(Hrvatska) Croatia(Hrvatska) Serbia(Hrvatska) Montenegro(Hrvatska) Bosnia and Herzegovina(Hrvatska) Lithuania(lietuvių) Spain(Português) Switzerland(Deutsch) United Kingdom(English)
Azië/Pacific
Japan(日本語) Korea(한국의) Thailand(ภาษาไทย) Malaysia(Melayu) Singapore(Melayu) Vietnam(Tiếng Việt) Philippines(Pilipino)
Afrika, India en Midden -Oosten
United Arab Emirates(العربية) Iran(فارسی) Tajikistan(فارسی) India(हिंदी) Madagascar(malaɡasʲ)
Zuid -Amerika / Oceanië
New Zealand(Maori) Brazil(Português) Angola(Português) Mozambique(Português)
Noord -Amerika
United States(English) Canada(English) Haiti(Ayiti) Mexico(español)
HuisproductenGeïntegreerde schakelingen (IC's)Logica - FIFOs Geheugen

Logica - FIFOs Geheugen

4,224 -producten gevonden

Product lijst

1...70717273747576...85
Vergelijken Beeld Deel # Fabrikant Beschrijving Inventaris Datasheets RoHS bus Directional Pakket Base Productnummer FWFT Ondersteuning retransmit Capability Programmeerbare Flags Ondersteuning Expansion Type Access Time Datasnelheid Geheugen grootte Current - Supply (Max) Functie Voltage - Levering Leverancier Device Pakket Verpakking / doos montage Type Temperatuur Serie Aantal stuks
72825LB10PFG 72825LB10PFG Renesas Electronics America Inc IC FIFO 1024X18 SYNC DL 128TQFP Op voorraad30741 pcs   Bi-Directional Tray 72825 Yes No Yes Depth, Width 6.5ns 100MHz 36K (1K x 18 x 2) 100mA Synchronous 4.5 V ~ 5.5 V 128-TQFP (14x20) 128-LQFP Surface Mount 0°C ~ 70°C 7200
67C4033-15NL 67C4033-15NL Advanced Micro Devices FIFO, 64X5, ASYNCHRONOUS Op voorraad47533 pcs   Uni-Directional Bulk 67C4033 No No No Depth, Width - 15MHz 64 x 5 45mA Asynchronous 4.5 V ~ 5.5 V 20-PDIP 20-DIP Through Hole 0°C ~ 70°C -
SN74V263-10GGM SN74V263-10GGM Texas Instruments IC SYNC FIFO 8KX18 100BGA Op voorraad9573 pcs SN74V263-10GGM.pdf Uni-Directional Tray 74V263 Yes Yes Yes Depth, Width 6.5ns 100MHz 144K (8K x 18)(16K x 9) 35mA Synchronous 3.15 V ~ 3.45 V 100-BGA MICROSTAR (10x10) 100-LFBGA Surface Mount 0°C ~ 70°C 74V
7200L15TP 7200L15TP Renesas Electronics America Inc IC MEM FIFO 256X9 15NS 28DIP Op voorraad5862 pcs 7200L15TP.pdf Uni-Directional Tube 7200 No Yes No Depth, Width 15ns 40MHz 2.25K (256 x 9) 80mA Asynchronous 4.5 V ~ 5.5 V 28-PDIP 28-DIP (0.300', 7.62mm) Through Hole 0°C ~ 70°C 7200
72V3690L6PFG8 72V3690L6PFG8 Renesas Electronics America Inc IC FIFO SS 32768X36 6NS 128-TQFP Op voorraad8612 pcs 72V3690L6PFG8.pdf Uni-Directional Tape & Reel (TR) 72V3690 Yes Yes Yes Depth, Width 4ns 166MHz 1.125M (32K x 36) 40mA Synchronous 3.15 V ~ 3.45 V 128-TQFP (14x20) 128-LQFP Surface Mount 0°C ~ 70°C 72V
72V221L15J8 72V221L15J8 Renesas Electronics America Inc IC FIFO SYNC 1KX9 15NS 32PLCC Op voorraad13038 pcs 72V221L15J8.pdf Uni-Directional Tape & Reel (TR) 72V221 No No Yes Depth, Width 10ns 66.7MHz 9K (1K x 9) 20mA Synchronous 3 V ~ 3.6 V 32-PLCC (14x11.46) 32-LCC (J-Lead) Surface Mount 0°C ~ 70°C 72V
72205LB25TFI8 72205LB25TFI8 Renesas Electronics America Inc IC FIFO 256X18 SYNC 25NS 64STQFP Op voorraad4233 pcs 72205LB25TFI8.pdf Uni-Directional Tape & Reel (TR) 72205 No No Yes Depth, Width 15ns 40MHz 4.5K (256 x 18) 60mA Synchronous 4.5 V ~ 5.5 V 64-TQFP (10x10) 64-LQFP Surface Mount -40°C ~ 85°C 7200
72271LA10PF8 72271LA10PF8 Renesas Electronics America Inc IC FIFO 16384X18 LP 10NS 64QFP Op voorraad14222 pcs   Uni-Directional Tape & Reel (TR) 72271 Yes Yes Yes Depth, Width 8ns 100MHz 288K (32K x 9) 75mA Synchronous 4.5 V ~ 5.5 V 64-TQFP (14x14) 64-LQFP Surface Mount 0°C ~ 70°C 7200
7200L15SOGI 7200L15SOGI Renesas Electronics America Inc IC MEM FIFO 256X9 15NS 28-SOIC Op voorraad28841 pcs 7200L15SOGI.pdf Uni-Directional Tube 7200 No Yes No Depth, Width 15ns 40MHz 2.25K (256 x 9) 80mA Asynchronous 4.5 V ~ 5.5 V 28-SOIC 28-SOIC (0.345", 8.77mm Width) Surface Mount -40°C ~ 85°C 7200
IDT72V36104L10PF8 IDT72V36104L10PF8 Renesas Electronics America Inc IC FIFO 131KX36 10NS 128QFP Op voorraad14793 pcs IDT72V36104L10PF8.pdf Bi-Directional Tape & Reel (TR) 72V36104 Yes Yes Yes Width 6.5ns 100MHz 4.5M (64K x 36 x 2) 400mA Synchronous 3.15 V ~ 3.45 V 128-TQFP (14x20) 128-LQFP Surface Mount 0°C ~ 70°C 72V
72V215L10TF 72V215L10TF Renesas Electronics America Inc IC FIFO SYNC 512X18 10NS 64STQFP Op voorraad15760 pcs 72V215L10TF.pdf Uni-Directional Tray 72V215 Yes No Yes Depth, Width 6.5ns 100MHz 9K (512 x 18) 30mA Synchronous 3 V ~ 3.6 V 64-TQFP (10x10) 64-LQFP Surface Mount 0°C ~ 70°C 72V
72V265LA15TFI 72V265LA15TFI Renesas Electronics America Inc IC FIFO SS 16384X18 15NS 64STQFP Op voorraad12033 pcs 72V265LA15TFI.pdf Uni-Directional Tray 72V265 Yes Yes Yes Depth, Width 10ns 66.7MHz 288K (16K x 18) 55mA Synchronous 3 V ~ 3.6 V 64-TQFP (10x10) 64-LQFP Surface Mount -40°C ~ 85°C 72V
72V03L15JG 72V03L15JG Renesas Electronics America Inc IC ASYNCH 2048X9 15NS 32-PLCC Op voorraad34165 pcs 72V03L15JG.pdf Uni-Directional Tube 72V03 No Yes No Depth, Width 15ns 40MHz 18K (2K x 9) 60mA Asynchronous 3 V ~ 3.6 V 32-PLCC (14x11.46) 32-LCC (J-Lead) Surface Mount 0°C ~ 70°C 72V
72215LB10PF 72215LB10PF Renesas Electronics America Inc IC FIFO 512X18 SYNC 10NS 64-TQFP Op voorraad15021 pcs 72215LB10PF.pdf Uni-Directional Tray 72215 No No Yes Depth, Width 6.5ns 100MHz 9K (512 x 18) 60mA Synchronous 4.5 V ~ 5.5 V 64-TQFP (14x14) 64-LQFP Surface Mount 0°C ~ 70°C 7200
72V293L10PF 72V293L10PF Renesas Electronics America Inc IC FIFO 65536X18 10NS 80QFP Op voorraad11177 pcs 72V293L10PF.pdf Uni-Directional Tray 72V293 Yes Yes Yes Depth, Width 6.5ns 100MHz 1.125M (64K x 18)(128K x 9) 35mA Synchronous 3.15 V ~ 3.45 V 80-TQFP (14x14) 80-LQFP Surface Mount 0°C ~ 70°C 72V
CY7C4275V-10ASC CY7C4275V-10ASC Infineon Technologies IC DEEP SYN FIFO 32KX18 64LQFP Op voorraad5890 pcs CY7C4275V-10ASC.pdf Uni-Directional Bag 7C4275 No Yes Yes Depth, Width 8ns 100MHz 576K (32K x 18) 30mA Synchronous 3 V ~ 3.6 V 64-TQFP (10x10) 64-LQFP Surface Mount 0°C ~ 70°C CY7C
74ACT2708PC 74ACT2708PC onsemi IC MEMORY FIRST OUT 64X9 28-DIP Op voorraad16191 pcs 74ACT2708PC.pdf Uni-Directional Tube 74ACT2708 No No No Width - 85MHz 576 (64 x 9) 150mA Asynchronous, Synchronous 4.5 V ~ 5.5 V 28-PDIP 28-DIP (0.600', 15.24mm) Through Hole -40°C ~ 85°C 74ACT
72V3613L20PF 72V3613L20PF Renesas Electronics America Inc IC FIFO CLOCK 64X36 20NS 120TQFP Op voorraad9704 pcs   Bi-Directional Tray 72V3613 No No Yes Width 12ns 50MHz 2.25K (64 x 36) - Synchronous 3 V ~ 3.6 V 120-TQFP (14x14) 120-LQFP Surface Mount 0°C ~ 70°C 72V
7284L15PA 7284L15PA Renesas Electronics America Inc IC FIFO 2048X18 15NS 56TSSOP Op voorraad16098 pcs   Uni-Directional Tube 7284 No Yes No Depth, Width 15ns 40MHz 72K (4K x 9 x 2) 150mA Asynchronous 4.5 V ~ 5.5 V 56-TSSOP 56-TFSOP (0.240', 6.10mm Width) Surface Mount 0°C ~ 70°C 7200
SN74ACT72241L35RJ SN74ACT72241L35RJ Texas Instruments FIFO, 4KX9, SYNCHRONOUS PQCC32 Op voorraad2374 pcs   - Bulk 74ACT72241 - - - - - - - - - - - - - - *
72V3664L15PF 72V3664L15PF Renesas Electronics America Inc IC FIFO 8192X36 15NS 128QFP Op voorraad10408 pcs   Bi-Directional Tray 72V3664 Yes Yes Yes Width 10ns 66.7MHz 288K (4K x 36 x 2) 400mA Synchronous 3 V ~ 3.6 V 128-TQFP (14x20) 128-LQFP Surface Mount 0°C ~ 70°C 72V
723642L12PF 723642L12PF Renesas Electronics America Inc IC FIFO SYNC 2048X36 120QFP Op voorraad11898 pcs 723642L12PF.pdf Bi-Directional Tray 723642 Yes No Yes Width 8ns 83MHz 72k (1k x 36 x 2) 400mA Synchronous 4.5 V ~ 5.5 V 120-TQFP (14x14) 120-LQFP Surface Mount 0°C ~ 70°C 7200
72401L35SO 72401L35SO Renesas Electronics America Inc IC FIFO PAR 64X4 35NS 16-SOIC Op voorraad3661 pcs 72401L35SO.pdf Uni-Directional Tube 72401 No No No Depth, Width 20ns 35MHz 256 (64 x 4) 35mA Asynchronous 4.5 V ~ 5.5 V 16-SOIC 16-SOIC (0.295", 7.50mm Width) Surface Mount 0°C ~ 70°C 7200
CY7C4255-10AXCT CY7C4255-10AXCT Infineon Technologies IC SYNC FIFO MEM 8KX18 64LQFP Op voorraad9053 pcs CY7C4255-10AXCT.pdf Uni-Directional Tape & Reel (TR) 7C4255 No Yes Yes Depth, Width 8ns 100MHz 144K (8K x 18) 45mA Synchronous 4.5 V ~ 5.5 V 64-TQFP (14x14) 64-LQFP Surface Mount 0°C ~ 70°C CY7C
CY7C4241-25JI CY7C4241-25JI Cypress Semiconductor Corp FIFO, 4KX9, 15NS, SYNCHRONOUS Op voorraad11752 pcs   Uni-Directional Bulk 7C4241 No No No Depth, Width 15ns 40MHz 1K x 9 40mA Asynchronous 4.5 V ~ 5.5 V 32-PLCC (11.43x13.97) 32-LCC (J-Lead) Surface Mount -40°C ~ 85°C CY7C
72V295L10PF 72V295L10PF Renesas Electronics America Inc IC FIFO SUPERSYNCII 10NS 64-TQFP Op voorraad6684 pcs 72V295L10PF.pdf Uni-Directional Tray 72V295 Yes Yes Yes Depth, Width 6.5ns 100MHz 2.25M (128K x 18) 60mA Synchronous 3 V ~ 3.6 V 64-TQFP (14x14) 64-LQFP Surface Mount 0°C ~ 70°C 72V
72V3640L6BCY 72V3640L6BCY Renesas Electronics America Inc IC FIFO SS 1024X36 6NS 144-BGA Op voorraad14183 pcs   Uni-Directional Tray 72V3640 Yes Yes Yes Depth, Width 4ns 166MHz 36K (1K x 36) 40mA Asynchronous, Synchronous 3.15 V ~ 3.45 V - - - 0°C ~ 70°C 72V
72281L10PFG8 72281L10PFG8 Renesas Electronics America Inc IC FIFO 32768X18 LP 10NS 64QFP Op voorraad10722 pcs 72281L10PFG8.pdf Uni-Directional Tape & Reel (TR) 72281 Yes Yes Yes Depth, Width 6.5ns 100MHz 576K (64K x 9) 80mA Synchronous 4.5 V ~ 5.5 V 64-TQFP (14x14) 64-LQFP Surface Mount 0°C ~ 70°C 7200
72V235L20PF 72V235L20PF Renesas Electronics America Inc IC FIFO SYNC 2048X18 20NS 64TQFP Op voorraad11461 pcs 72V235L20PF.pdf Uni-Directional Tray 72V235 Yes No Yes Depth, Width 12ns 50MHz 36K (2K x 18) 30mA Synchronous 3 V ~ 3.6 V 64-TQFP (14x14) 64-LQFP Surface Mount 0°C ~ 70°C 72V
72V295L15PFGI 72V295L15PFGI Renesas Electronics America Inc IC FIFO SUPERSYNCII 15NS 64-TQFP Op voorraad34345 pcs 72V295L15PFGI.pdf - Tube 72V295 Yes Yes Yes Depth, Width 10ns 66.7MHz 2.25M (128K x 18) 60mA Synchronous 3 V ~ 3.6 V 64-TQFP (14x14) 64-LQFP Surface Mount -40°C ~ 85°C 72V
72V253L7-5PFGI8 72V253L7-5PFGI8 Renesas Electronics America Inc IC FIFO 4096X18 7-5NS 80QFP Op voorraad40681 pcs 72V253L7-5PFGI8.pdf Uni-Directional Tape & Reel (TR) 72V253 Yes Yes Yes Depth, Width 5ns 133.3MHz 72K (4K x 18)(8K x 9) 35mA Synchronous 3.15 V ~ 3.45 V 80-TQFP (14x14) 80-LQFP Surface Mount -40°C ~ 85°C 72V
72V2105L15PFGI8 72V2105L15PFGI8 Renesas Electronics America Inc IC FIFO SUPERSYNCII 15NS 64-TQFP Op voorraad48940 pcs 72V2105L15PFGI8.pdf Uni-Directional Tape & Reel (TR) 72V2105 Yes Yes Yes Depth, Width 10ns 66.7MHz 4.5M (256K x 18) 60mA Synchronous 3 V ~ 3.6 V 64-TQFP (14x14) 64-LQFP Surface Mount -40°C ~ 85°C 72V
72V835L15PFI8 72V835L15PFI8 Renesas Electronics America Inc IC FIFO SYNC 2048X18 128QFP Op voorraad8151 pcs   Bi-Directional Tape & Reel (TR) 72V835 Yes No Yes Depth, Width 10ns 66.7MHz 72K (2K x 18 x 2) 60mA Synchronous 3 V ~ 3.6 V 128-TQFP (14x20) 128-LQFP Surface Mount -40°C ~ 85°C 72V
7205L50J8 7205L50J8 Renesas Electronics America Inc IC FIFO 4096X18 50NS 32PLCC Op voorraad12930 pcs 7205L50J8.pdf Uni-Directional Tape & Reel (TR) 7205 No Yes No Depth, Width 50ns 15MHz 72K (8K x 9) 120mA Asynchronous 4.5 V ~ 5.5 V 32-PLCC (14x11.46) 32-LCC (J-Lead) Surface Mount 0°C ~ 70°C 7200
72V845L10PF8 72V845L10PF8 Renesas Electronics America Inc IC FIFO SYNC 4096X18 128QFP Op voorraad6578 pcs 72V845L10PF8.pdf Bi-Directional Tape & Reel (TR) 72V845 Yes No Yes Depth, Width 6.5ns 100MHz 144K (4K x 18 x 2) 60mA Synchronous 3 V ~ 3.6 V 128-TQFP (14x20) 128-LQFP Surface Mount 0°C ~ 70°C 72V
SN74ABT7820-15PH SN74ABT7820-15PH Texas Instruments IC 512X18X2 BI-DIR MEM 80-QFP Op voorraad8549 pcs   Bi-Directional Tray 74ABT7820 No No Yes - 12ns 67MHz 18K (512 x 18 x 2) 95mA Asynchronous 4.5 V ~ 5.5 V 80-QFP (14x20) 80-BQFP Surface Mount 0°C ~ 70°C 74ABT
72401L10P 72401L10P Renesas Electronics America Inc IC FIFO PAR 64X4 10NS 16-DIP Op voorraad6440 pcs 72401L10P.pdf Uni-Directional Tray 72401 No No No Depth, Width 55ns 10MHz 256 (64 x 4) 35mA Asynchronous 4.5 V ~ 5.5 V 16-PDIP 16-DIP (0.300', 7.62mm) Through Hole 0°C ~ 70°C 7200
72V223L7-5PF8 72V223L7-5PF8 Renesas Electronics America Inc IC FIFO 512X18 7-5NS 80QFP Op voorraad11047 pcs 72V223L7-5PF8.pdf Uni-Directional Tape & Reel (TR) 72V223 Yes Yes Yes Depth, Width 5ns 133.3MHz 9K (512 x 18)(1K x 9) 35mA Synchronous 3.15 V ~ 3.45 V 80-TQFP (14x14) 80-LQFP Surface Mount 0°C ~ 70°C 72V
72241L15J 72241L15J Renesas Electronics America Inc IC FIFO 2048X18 SYNC 15NS 32PLCC Op voorraad6556 pcs 72241L15J.pdf Uni-Directional Tube 72241 No No Yes Depth, Width 10ns 66.7MHz 36K (4K x 9) 35mA Synchronous 4.5 V ~ 5.5 V 32-PLCC (14x11.46) 32-LCC (J-Lead) Surface Mount 0°C ~ 70°C 7200
CD74HCT7030E CD74HCT7030E Harris Corporation 64-WORD X 9-BIT FIFO REGISTER Op voorraad33954 pcs   - - - - - - - - - - - - - - - - - -
QS72221-20JR QS72221-20JR Quality Semiconductor QUALITY SEMI FIFO 1KX9 12NS SYNC Op voorraad31683 pcs   - - - - - - - - - - - - - - - - - -
7282L12PAGI8 Renesas Electronics America Inc IC SRAM Op voorraad14436 pcs   Bi-Directional Tape & Reel (TR) - No Yes No Depth, Width 12ns 50MHz 1K x 9 x 2 125mA Asynchronous 4.5 V ~ 5.5 V 56-TSSOP 56-TFSOP (0.240", 6.10mm Width) Surface Mount -40°C ~ 85°C 7200
72T36115L4-4BBG Renesas Electronics America Inc IC FIFO 131072X18 SYNC 240BGA Op voorraad11555 pcs 72T36115L4-4BBG.pdf Uni-Directional Tray 72T36115 Yes Yes Yes Depth, Width 8ns, 3.4ns 100MHz, 225MHz 4.5M (128K x 36) 90mA Asynchronous, Synchronous 2.375 V ~ 2.625 V 240-PBGA (19x19) 240-BGA Surface Mount 0°C ~ 70°C 72T
5962-8956807ZA Renesas Electronics America Inc LCC 11.40X13.97X1.78 MM, 1.27MM Op voorraad43014 pcs   Uni-Directional Tube 5962-8956807 No Yes No Depth, Width 20ns 33.3MHz 36K (4K x 9) 150mA Asynchronous 4.5 V ~ 5.5 V 32-LCC (13.97x11.43) 32-CLCC Surface Mount -55°C ~ 125°C 7200
72V201L15PFG Renesas Electronics America Inc IC SRAM Op voorraad7306 pcs   Uni-Directional Tray - No No Yes Depth, Width 10ns 66.7MHz 256 x 9 20mA Synchronous 3 V ~ 3.6 V 32-TQFP (7x7) 32-LQFP Surface Mount 0°C ~ 70°C 72V
72211L10JGI8 Renesas Electronics America Inc IC SRAM Op voorraad5183 pcs   Uni-Directional Tape & Reel (TR) - No No Yes Depth, Width 6.5ns 100MHz 512 x 9 35mA Asynchronous, Synchronous 4.5 V ~ 5.5 V 32-PLCC (14x11.46) 32-LCC (J-Lead) Surface Mount -40°C ~ 85°C 7200
72211L15PFG Renesas Electronics America Inc IC SRAM Op voorraad13641 pcs   Uni-Directional Tray - No No Yes Depth, Width 10ns 66.7MHz 512 x 9 35mA Asynchronous, Synchronous 4.5 V ~ 5.5 V 32-TQFP (7x7) 32-LQFP Surface Mount 0°C ~ 70°C 7200
7206L30LB Renesas Electronics America Inc IC MEM FIFO 16K X 9 ASYNC 32LCC Op voorraad10747 pcs 7206L30LB.pdf Uni-Directional Tube 7206 No Yes No Depth, Width 30ns 25MHz 144K (16K x 9) 150mA Asynchronous 4.5 V ~ 5.5 V 32-LCC (11.43x13.97) 32-CLCC Surface Mount -55°C ~ 125°C 7200
72215LB10J Renesas Electronics America Inc IC FIFO 512X18 SYNC 10NS 68-PLCC Op voorraad8653 pcs 72215LB10J.pdf Uni-Directional Tube 72215 No No Yes Depth, Width 6.5ns 100MHz 9K (512 x 18) 60mA Synchronous 4.5 V ~ 5.5 V 68-PLCC (24.21x24.21) 68-LCC (J-Lead) Surface Mount 0°C ~ 70°C 7200
72V251L20PFGI8 Renesas Electronics America Inc IC SRAM Op voorraad11283 pcs   Uni-Directional Tape & Reel (TR) - No No Yes Depth, Width 12ns 50MHz 8k x 9 20mA Synchronous 3 V ~ 3.6 V 32-TQFP (7x7) 32-LQFP Surface Mount -40°C ~ 85°C 72V
1...70717273747576...85
0 RFQ
Winkelmand (0 Items)
Het is leeg.
Vergelijk lijst (0 Items)
Het is leeg.
Feedback

Uw feedback is belangrijk!Bij Allelco waarderen we de gebruikerservaring en streven we ernaar deze constant te verbeteren.
Deel uw opmerkingen met ons via ons feedbackformulier en we zullen onmiddellijk reageren.
Bedankt voor het kiezen van Allelco.

Onderwerp
E-mail
Comments
Captcha
Sleep of klik om het bestand te uploaden
Upload bestand
Typen: .xls, .xlsx, .doc, .Docx, .jpg, .png en .pdf.
MAX -bestandsgrootte: 10 MB