Poglej vse

English različico upoštevajte kot našo uradno različico.Vrnitev

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) Japan(日本語) Korea(한국의) Thailand(ภาษาไทย) Malaysia(Melayu) Singapore(Melayu) Vietnam(Tiếng Việt) Philippines(Pilipino) United Arab Emirates(العربية) Iran(فارسی) Tajikistan(فارسی) India(हिंदी) Madagascar(malaɡasʲ) New Zealand(Maori) Brazil(Português) Angola(Português) Mozambique(Português) United States(English) Canada(English) Haiti(Ayiti) Mexico(español)
DomovIzdelkiIntegriranih vezij (IC)PMIC - Nadzorniki

PMIC - Nadzorniki

Najdeni izdelki 7,505

Seznam izdelkov

1...28293031323334...151
Primerjaj Slika Del # Proizvajalec Opis Popis ECAD model RoHS Številka osnovnega dela Izhod Ponastaviti Število nadzorovanih napetosti Ponastavitev časovnega zakasnitve Napetost - Prag Pakiranje Status svobodnega statusa / RoHS Raven občutljivosti na vlago (MSL) Številka osnovnega izdelka Paket Proizvajalec Standardni čas vodenja natančen opis Serija delovna temperatura Tip montaže Tip Paket / primer Paket naprave za dobavitelja Količina
MAX6316LUK29AX+T MAX6316LUK29AX+T Analog Devices Inc./Maxim Integrated IC SUPERVISOR 1 CHANNEL SOT23-5 Na zalogi12307 pcs - Push-Pull, Totem Pole Active Low 1 1ms Minimum 2.93V - - - MAX6316 Tape & Reel (TR) - - - -40°C ~ 125°C (TA) Surface Mount Simple Reset/Power-On Reset SC-74A, SOT-753 SOT-23-5
ADM1186-2ARQZ-REEL ADM1186-2ARQZ-REEL Analog Devices Inc. IC SUPERVISOR 4 CHANNEL 16QSOP Na zalogi13366 pcs - Open Drain or Open Collector Active High 4 - Adjustable/Selectable - - - ADM1186 Tape & Reel (TR) - - - -40°C ~ 85°C (TA) Surface Mount Sequencer 16-SSOP (0.154', 3.90mm Width) 16-QSOP
MAX16002ATC+ MAX16002ATC+ Analog Devices Inc./Maxim Integrated IC SUPERVISOR 4 CHANNEL 12TQFN Na zalogi5230 pcs - Open Drain or Open Collector Active Low 4 Adjustable/Selectable 1.8V, 2.5V, 3.3V, Adj - - - MAX16002 Tube - - - -40°C ~ 125°C (TA) Surface Mount Multi-Voltage Supervisor 12-WQFN Exposed Pad 12-TQFN (4x4)
MAX1232CPA+ MAX1232CPA+ Analog Devices Inc./Maxim Integrated IC SUPERVISOR 1 CHANNEL 8DIP Na zalogi16683 pcs - Open Drain or Open Collector Active High/Active Low 1 250ms Minimum 4.37V, 4.62V - - - MAX1232 Tube - - - 0°C ~ 70°C (TA) Through Hole Simple Reset/Power-On Reset 8-DIP (0.300', 7.62mm) 8-PDIP
LM3724EM5X-2.32 LM3724EM5X-2.32 Texas Instruments IC SUPERVISOR 1 CHANNEL SOT23-5 Na zalogi6850 pcs - Open Drain or Open Collector Active Low 1 100ms Minimum 2.32V - - - LM3724 Tape & Reel (TR) - - - -40°C ~ 125°C (TA) Surface Mount Simple Reset/Power-On Reset SC-74A, SOT-753 SOT-23-5
MAX812MEUS+T MAX812MEUS+T Analog Devices Inc./Maxim Integrated IC SUPERVISOR 1 CHANNEL SOT143-4 Na zalogi12798 pcs - Push-Pull, Totem Pole Active High 1 140ms Minimum 4.38V - - - MAX812 Tape & Reel (TR) - - - -40°C ~ 85°C (TA) Surface Mount Simple Reset/Power-On Reset TO-253-4, TO-253AA SOT-143-4
R3117K241A-TR R3117K241A-TR Nisshinbo Micro Devices Inc. IC SUPERVISOR 1 CHANNEL 4DFN Na zalogi133670 pcs - Open Drain or Open Collector Active Low 1 80µs Typical 2.4V - - - R3117 Tape & Reel (TR) - - R3117x -40°C ~ 105°C Surface Mount Voltage Detector 4-UDFN Exposed Pad DFN(PL)1010-4
S-1000N28-N4T1G S-1000N28-N4T1G ABLIC Inc. IC SUPERVISOR 1 CHANNEL SC82AB Na zalogi102750 pcs - Open Drain or Open Collector Active Low 1 - 2.8V - - - S-1000 Tape & Reel (TR) - - S-1000 -40°C ~ 85°C (TA) Surface Mount Voltage Detector SC-82A, SOT-343 SC-82AB
BD4942FVE-TR BD4942FVE-TR LAPIS Semiconductor IC DETECTOR VOLT 4.2V CMOS 5VSOF Na zalogi263830 pcs BD49 Push-Pull, Totem Pole Active Low 1 - 4.2V Tape & Reel (TR) Lead free / RoHS Compliant 1 (Unlimited) - - 6 Weeks Supervisor Push-Pull, Totem Pole 1 Channel 5-VSOF BD49xxx -40°C ~ 105°C (TA) Surface Mount Voltage Detector SOT-665 5-VSOF
MAX824SEUK+T MAX824SEUK+T Analog Devices Inc./Maxim Integrated IC SUPERVISOR 1 CHANNEL SOT23-5 Na zalogi14864 pcs - Push-Pull, Totem Pole Active High/Active Low 1 140ms Minimum 2.93V - - - MAX824 Tape & Reel (TR) - - - -40°C ~ 125°C (TA) Surface Mount Simple Reset/Power-On Reset SC-74A, SOT-753 SOT-23-5
TL7759CDR TL7759CDR Texas Instruments IC SUPERVISOR 1 CHANNEL 8SOIC Na zalogi112130 pcs - Push-Pull, Totem Pole Active High 1 5µs Maximum Propagation Delay 4.55V - - - TL7759 Tape & Reel (TR) - - - 0°C ~ 70°C (TA) Surface Mount Simple Reset/Power-On Reset 8-SOIC (0.154", 3.90mm Width) 8-SOIC
ADM696SQ ADM696SQ Analog Devices Inc. IC SUPERVISOR 1 CHANNEL 16CDIP Na zalogi2059 pcs - Push-Pull, Push-Pull Active High/Active Low 1 35ms Minimum 1.3V - - - ADM696 Tube - - - -55°C ~ 125°C (TA) Through Hole Battery Backup Circuit 16-CDIP (0.300', 7.62mm) 16-CERDIP
MAX6315US44D3+T MAX6315US44D3+T Analog Devices Inc./Maxim Integrated IC SUPERVISOR 1 CHANNEL SOT143-4 Na zalogi19873 pcs - Open Drain or Open Collector Active Low 1 140ms Minimum 4.39V - - - MAX6315 Tape & Reel (TR) - - - -40°C ~ 125°C (TA) Surface Mount Simple Reset/Power-On Reset TO-253-4, TO-253AA SOT-143-4
TPS3126E15DBVR TPS3126E15DBVR Texas Instruments IC SUPERVISOR 1 CHANNEL SOT23-5 Na zalogi27800 pcs - Open Drain or Open Collector Active Low 1 100ms Minimum 1.43V - - - TPS3126 Tape & Reel (TR) - - - -40°C ~ 85°C (TA) Surface Mount Simple Reset/Power-On Reset SC-74A, SOT-753 SOT-23-5
TPS3839A09DBZR TPS3839A09DBZR Texas Instruments IC SUPERVISOR 1 CHANNEL SOT23-3 Na zalogi211790 pcs - Push-Pull, Totem Pole Active Low 1 120ms Minimum 0.9V - - - TPS3839 Tape & Reel (TR) - - - -40°C ~ 85°C (TA) Surface Mount Simple Reset/Power-On Reset TO-236-3, SC-59, SOT-23-3 SOT-23-3
CAT823RSDI-GT3 CAT823RSDI-GT3 onsemi IC SUPERVISOR 1 CHANNEL SC70-5 Na zalogi4740 pcs - Push-Pull, Totem Pole Active Low 1 140ms Minimum 2.63V - - - CAT823 Tape & Reel (TR) - - - -40°C ~ 85°C (TA) Surface Mount Simple Reset/Power-On Reset 5-TSSOP, SC-70-5, SOT-353 SC-70-5
NCP304LSQ38T1 NCP304LSQ38T1 onsemi IC SUPERVISOR 1 CHANNEL SC82AB Na zalogi17090 pcs - Push-Pull, Totem Pole Active Low 1 - 3.8V - - - NCP304 Tape & Reel (TR) - - - -40°C ~ 85°C (TA) Surface Mount Simple Reset/Power-On Reset SC-82A, SOT-343 SC-82AB
BU4212G-TR BU4212G-TR Rohm Semiconductor IC SUPERVISOR 1 CHANNEL 5SSOP Na zalogi129120 pcs - Open Drain or Open Collector Active Low 1 Adjustable/Selectable 1.2V - - - BU4212 Tape & Reel (TR) - - - -40°C ~ 125°C (TA) Surface Mount Simple Reset/Power-On Reset SC-74A, SOT-753 5-SSOP
X5649S14-2.7 X5649S14-2.7 Renesas Electronics America Inc IC SUPERVISOR 1 CHANNEL 14SOIC Na zalogi4540 pcs - Open Drain or Open Collector Active High 1 100ms Minimum 2.63V - - - X5649 Tube - - - 0°C ~ 70°C (TA) Surface Mount Simple Reset/Power-On Reset 14-SOIC (0.154", 3.90mm Width) 14-SOIC
BU4222F-TR BU4222F-TR Rohm Semiconductor IC SUPERVISOR 1 CHANNEL 4SOP Na zalogi148460 pcs - Open Drain or Open Collector Active Low 1 Adjustable/Selectable 2.2V - - - BU4222 Tape & Reel (TR) - - - -40°C ~ 125°C (TA) Surface Mount Simple Reset/Power-On Reset SC-82 4-SOP
MAX707ESA-TG MAX707ESA-TG onsemi IC SUPERVISOR PWR SUP SUPPORT Na zalogi199380 pcs - Push-Pull, Push-Pull Active High/Active Low 1 140ms Minimum 4.65V - - - MAX707 Bulk - - - -40°C ~ 85°C (TA) Surface Mount Simple Reset/Power-On Reset 8-SOIC (0.154", 3.90mm Width) 8-SOIC
MAX6730AUTRD3+T MAX6730AUTRD3+T Analog Devices Inc./Maxim Integrated IC SUPERVISOR MPU W/WD SOT23-6 Na zalogi18154 pcs - Open Drain or Open Collector Active Low 1 140ms Minimum 2.625V - - - MAX6730 Tape & Reel (TR) - - - -40°C ~ 125°C (TA) Surface Mount Simple Reset/Power-On Reset SOT-23-6 SOT-6
ADM8694AN ADM8694AN Analog Devices Inc. IC SUPERVISOR MPU 4.65V 16DIP Na zalogi7952 pcs - Push-Pull, Totem Pole Active Low 1 140ms Minimum 4.65V - - - ADM8694 Tube - - - -40°C ~ 85°C Through Hole Battery Backup Circuit 16-DIP (0.300", 7.62mm) 16-PDIP
MAX6352SVUK MAX6352SVUK Analog Devices Inc./Maxim Integrated IC SUPERVISOR 2 CHANNEL SOT23-5 Na zalogi15588 pcs - Open Drain or Open Collector Active Low 2 100ms Minimum 1.58V, 2.93V - - - MAX6352 Bulk - - - -40°C ~ 85°C (TA) Surface Mount Multi-Voltage Supervisor SC-74A, SOT-753 SOT-23-5
MAX825SEUK MAX825SEUK Analog Devices Inc./Maxim Integrated IC SUPERVISOR MPU Na zalogi16114 pcs - Push-Pull, Totem Pole Active High/Active Low 1 140ms Minimum 2.93V - - - MAX825 Bulk - - - -40°C ~ 125°C (TA) Surface Mount Simple Reset/Power-On Reset SC-74A, SOT-753 SOT-23-5
STM707M6F STM707M6F STMicroelectronics IC SUPERVISOR 1 CHANNEL 8SOIC Na zalogi41960 pcs - Push-Pull, Totem Pole Active High/Active Low 1 140ms Minimum 4.63V - - - STM707 Tape & Reel (TR) - - - -40°C ~ 85°C (TA) Surface Mount Simple Reset/Power-On Reset 8-SOIC (0.154", 3.90mm Width) 8-SOIC
S-80820CNPF-B8FTFU S-80820CNPF-B8FTFU ABLIC Inc. IC SUPERVISOR 1 CHANNEL SNT-4A Na zalogi113980 pcs - Open Drain or Open Collector Active Low 1 - 2V - - - S-80820 Tape & Reel (TR) - - S-808xxC -40°C ~ 85°C (TA) Surface Mount Voltage Detector 4-SMD, Flat Leads SNT-4A
S-80938CNNB-G88T2U S-80938CNNB-G88T2U ABLIC Inc. IC SUPERVISOR 1 CHANNEL SC82AB Na zalogi94400 pcs - Open Drain or Open Collector Active Low 1 20ms Minimum 3.8V - - - S-80938 Tape & Reel (TR) - - S-809xxC -40°C ~ 85°C (TA) Surface Mount Voltage Detector SC-82A, SOT-343 SC-82AB
DS1834AS+T&R DS1834AS+T&R Analog Devices Inc./Maxim Integrated IC SUPERVISOR 2 CHANNEL 8SOIC Na zalogi26502 pcs - Open Drain or Open Collector Active Low 2 200ms Minimum 3.3V, 5V - - - DS1834 Tape & Reel (TR) - - EconoReset -40°C ~ 85°C (TA) Surface Mount Multi-Voltage Supervisor 8-SOIC (0.154', 3.90mm Width) 8-SOIC
TCM809RVNB713 TCM809RVNB713 Microchip Technology IC SUPERVISOR 1 CHANNEL SOT23-3 Na zalogi88300 pcs - Push-Pull, Totem Pole Active Low 1 140ms Minimum 2.63V - - - TCM809 Tape & Reel (TR) - - - -40°C ~ 125°C (TA) Surface Mount Simple Reset/Power-On Reset TO-236-3, SC-59, SOT-23-3 SOT-23-3
MAX8215CPD MAX8215CPD Analog Devices Inc./Maxim Integrated IC SUPERVISOR MPU VOLT MONITOR Na zalogi13757 pcs - Open Drain or Open Collector - 5 20µs Typical Propagation Delay ±5V, ±12V, Adj - - - MAX8215 Bulk - - - 0°C ~ 70°C (TA) Through Hole Multi-Voltage Supervisor 14-DIP (0.300", 7.62mm) 14-PDIP
S-80817CNMC-B8CT2G S-80817CNMC-B8CT2G ABLIC Inc. IC SUPERVISOR 1 CHANNEL SOT23-5 Na zalogi104420 pcs - Open Drain or Open Collector Active Low 1 - 1.7V - - - S-80817 Tape & Reel (TR) - - S-808xxC -40°C ~ 85°C (TA) Surface Mount Voltage Detector SC-74A, SOT-753 SOT-23-5
NCP301LSN45T1 NCP301LSN45T1 onsemi IC SUPERVISOR 1 CHANNEL 5TSOP Na zalogi16630 pcs - Open Drain or Open Collector Active Low 1 - 4.5V - - - NCP301 Tape & Reel (TR) - - - -40°C ~ 125°C (TA) Surface Mount Simple Reset/Power-On Reset SOT-23-5 Thin, TSOT-23-5 5-TSOP
BD5234G-TR BD5234G-TR Rohm Semiconductor IC SUPERVISOR 1 CHANNEL 5SSOP Na zalogi232480 pcs - Open Drain or Open Collector Active Low 1 - 3.4V - - - BD5234 Tape & Reel (TR) - - BD52xx -40°C ~ 105°C (TA) Surface Mount Voltage Detector SC-74A, SOT-753 5-SSOP
ADM705AR-REEL7 ADM705AR-REEL7 Analog Devices Inc. IC SUPERVISOR 1 CHANNEL 8SOIC Na zalogi5350 pcs - Push-Pull, Totem Pole Active Low 1 160ms Minimum 4.65V - - - ADM705 Tape & Reel (TR) - - - -40°C ~ 85°C (TA) Surface Mount Simple Reset/Power-On Reset 8-SOIC (0.154', 3.90mm Width) 8-SOIC
NCP803SN293T1 NCP803SN293T1 onsemi IC SUPERVISOR 1 CHANNEL SOT23-3 Na zalogi10520 pcs - Open Drain or Open Collector Active Low 1 140ms Minimum 2.93V - - - NCP803 Tape & Reel (TR) - - - -40°C ~ 105°C (TJ) Surface Mount Simple Reset/Power-On Reset TO-236-3, SC-59, SOT-23-3 SOT-23-3 (TO-236)
TS831-5IPT TS831-5IPT STMicroelectronics IC SUPERVISOR 1 CHANNEL 8TSSOP Na zalogi7850 pcs - Open Drain or Open Collector Active Low 1 20µs Typical Response Time 4.33V - - - TS831 Tape & Reel (TR) - - - -40°C ~ 125°C (TA) Surface Mount Simple Reset/Power-On Reset 8-TSSOP (0.173", 4.40mm Width) 8-TSSOP
MAX6753KA31+T MAX6753KA31+T Analog Devices Inc./Maxim Integrated IC SUPERVISOR 1 CHANNEL SOT23-8 Na zalogi10345 pcs - Open Drain or Open Collector Active Low 1 Adjustable/Selectable 3.075V - - - MAX6753 Tape & Reel (TR) - - - -40°C ~ 125°C (TA) Surface Mount Simple Reset/Power-On Reset SOT-23-8 SOT-23-8
TPS386000RGPR TPS386000RGPR Texas Instruments IC SUPERVISOR 4 CHANNEL 20QFN Na zalogi20282 pcs - Open Drain or Open Collector Active Low 4 Adjustable/Selectable Adjustable/Selectable - - - TPS386000 Tape & Reel (TR) - - - -40°C ~ 125°C (TJ) Surface Mount Multi-Voltage Supervisor 20-VFQFN Exposed Pad 20-QFN (4x4)
STM6322SWY6F STM6322SWY6F STMicroelectronics IC SUPERVISOR 1 CHANNEL SOT23-5 Na zalogi32141 pcs - Open Drain, Push-Pull Active High/Active Low 1 140ms Minimum 2.93V - - - STM6322 Tape & Reel (TR) - - - -40°C ~ 85°C (TA) Surface Mount Simple Reset/Power-On Reset SC-74A, SOT-753 SOT-23-5
S-80855CNMC-B9GT2U S-80855CNMC-B9GT2U ABLIC Inc. IC SUPERVISOR 1 CHANNEL SOT23-5 Na zalogi79750 pcs - Open Drain or Open Collector Active Low 1 - 5.5V - - - S-80855 Tape & Reel (TR) - - S-808xxC -40°C ~ 85°C (TA) Surface Mount Voltage Detector SC-74A, SOT-753 SOT-23-5
X5165S8 X5165S8 Renesas Electronics America Inc IC SUPERVISOR 1 CHANNEL 8SOIC Na zalogi13420 pcs - Open Drain or Open Collector Active High 1 100ms Minimum 4.38V - - - X5165 Tube - - - 0°C ~ 70°C (TA) Surface Mount Simple Reset/Power-On Reset 8-SOIC (0.154', 3.90mm Width) 8-SOIC
MAX6315US48D2+T MAX6315US48D2+T Analog Devices Inc./Maxim Integrated IC SUPERVISOR 1 CHANNEL SOT143-4 Na zalogi13470 pcs - Open Drain or Open Collector Active Low 1 20ms Minimum 4.8V - - - MAX6315 Tape & Reel (TR) - - - -40°C ~ 125°C (TA) Surface Mount Simple Reset/Power-On Reset TO-253-4, TO-253AA SOT-143-4
MAX6806UR23 MAX6806UR23 Analog Devices Inc./Maxim Integrated IC SUPERVISOR 1 CHANNEL 8UMAX Na zalogi17492 pcs - Push-Pull, Totem Pole Active Low 1 30µs Typical 4.6V - - - MAX6806 Bulk - - - -40°C ~ 85°C (TA) Surface Mount Simple Reset/Power-On Reset 8-TSSOP, 8-MSOP (0.118", 3.00mm Width) 8-µMAX
MC34164P-5RP MC34164P-5RP onsemi IC SUPERVISOR 1 CHANNEL TO92-3 Na zalogi4370 pcs - Open Drain or Open Collector Active Low 1 - 4.33V - - - MC34164 Tape & Box (TB) - - - 0°C ~ 70°C (TA) Through Hole Simple Reset/Power-On Reset TO-226-3, TO-92-3 Long Body (Formed Leads) TO-92 (TO-226)
NCP301LSN30T1G NCP301LSN30T1G onsemi IC SUPERVISOR 1 CHANNEL 5TSOP Na zalogi7490 pcs - Open Drain or Open Collector Active Low 1 - 3V - - - NCP301 Tape & Reel (TR) - - - -40°C ~ 125°C (TA) Surface Mount Simple Reset/Power-On Reset SOT-23-5 Thin, TSOT-23-5 5-TSOP
CAT809STBI-GT3 CAT809STBI-GT3 onsemi IC SUPERVISOR 1 CHANNEL SOT23-3 Na zalogi127950 pcs - Push-Pull, Totem Pole Active Low 1 140ms Minimum 2.93V - - - CAT809 Tape & Reel (TR) - - - -40°C ~ 85°C (TA) Surface Mount Simple Reset/Power-On Reset TO-236-3, SC-59, SOT-23-3 SOT-23-3
LTC2916IDDB-1#TRPBF LTC2916IDDB-1#TRPBF Analog Devices Inc. IC SUPERVISOR 1 CHANNEL 8DFN Na zalogi22829 pcs - Open Drain or Open Collector Active Low 1 150ms Minimum 27 Selectable Threshold Combinations - - - LTC2916 Tape & Reel (TR) - - - -40°C ~ 85°C (TA) Surface Mount Multi-Voltage Supervisor 8-WFDFN Exposed Pad 8-DFN (3x2)
TC54VC4502ECB713 TC54VC4502ECB713 Microchip Technology IC SUPERVISOR 1 CHANNEL SOT23A-3 Na zalogi86540 pcs - Push-Pull, Totem Pole Active Low 1 - 4.5V - - - TC54VC Tape & Reel (TR) - - - -40°C ~ 85°C (TA) Surface Mount Simple Reset/Power-On Reset TO-236-3, SC-59, SOT-23-3 SOT-23A-3
S-80831CNMC-B8QT2G S-80831CNMC-B8QT2G ABLIC Inc. IC SUPERVISOR 1 CHANNEL SOT23-5 Na zalogi127280 pcs - Open Drain or Open Collector Active Low 1 - 3.1V - - - S-80831 Tape & Reel (TR) - - S-808xxC -40°C ~ 85°C (TA) Surface Mount Voltage Detector SC-74A, SOT-753 SOT-23-5
1...28293031323334...151
0 RFQ
Nakupovalni voziček (0 Items)
Je prazno.
Primerjajte seznam (0 Items)
Je prazno.
Povratne informacije

Vaše povratne informacije so pomembne!Pri Allelco cenimo uporabniško izkušnjo in si prizadevamo, da bi jo nenehno izboljševali.
Prosimo, da svoje komentarje delite z nami prek našega obrazca za povratne informacije in takoj se bomo odzvali.
Hvala, ker ste izbrali Allelco.

Tema
E-naslov
Komentarji
Captcha
Povlecite ali kliknite za nalaganje datoteke
Naloži datoteko
Vrste: .xls, .xlsx, .doc, .docx, .jpg, .png in .pdf.
Max File Velikost: 10MB