80C51 Core Variants and Vendors Overview
Simply the most sourced uC. Period.

The long proven 80C51 continues to add variants, and suppliers. Even Microchip now sell 80C51! (SST,SMSC)

A couple of vendors now deliver Dual Core 8051's
With expanding QuadSPI memory choices, we also see the first C51's offering Execute-In-Place from 8 pin SPI memory
12 Bit ADC is moving to be more mainstream. Advanced Analog performance (16/20+ ADC bits) is available from Analog Devices, TI, SiLabs, Maxim, Nuvoton etc.

Small packages: 2mm(+)/3mm/4mm etc, and SO8/MSOP10/SO14/SO16 are now design choices.
Another trend sees C51's moving into system chips, as the on-chip controller.
USB 2.0 480MBaud, USB-OTG, Ethernet, Power Line Comms, and BlueTooth systems are all seeing C51 cores.
Silabs and NXP drive the 80C51 in FLASH well under $1 and to 14/11/8pins
Single cycle 80C51 cores are expanding all the time.
On chip regulators, and low power, Calibrated Oscillators are also emerging trends.
Many far-east chip vendors and foundries are now backing the 80C51.

Wide Vcc is expanding again: after some moves to 3V, NXP, SiLabs, Nuvoton all offer wide Supply parts.
This allows direct drive of Power MOSFETS, and 5V Analog Swings, and reduces BOMs
Zilog & Fairchild & FTDI have now joined the 8051 supplier camp.
ABOV New 4K..128KF, MC95/MC96/MC97, 12b ADC, Wide Vcc, LCD, small packages 8p-100p
ABOV Documents update summary
ABOV MCU finder 8-bit M8051 MC96F MC97F etc
Summary of all ABOV M8051 2T Combi MC95FGxx and MC96FCxx families (chipswork tw)
Google translate Summary of ABOV M8051 2T Combi MC95FGxx and MC96FCxx families (chipswork)
Acer Laboratories Inc. 64K MTP 'C52 M6759,44p; (M5617,100p; M5705,208p; etc)
Aeroflex UTMC Aerospace RadHard UT69RH051
Analog Devices MicroConverters TSSOP28/QFP52/MLF56, 8K/62K, 12/16/24 Bit ADC ADuC814/12/16/24/31/32/34/36 + ARM uC
Analog Devices ADuC84x RISC 1 Cycle 25MIPS.5V 16MIPS.3V 400ksps 12 bit ADC
Analog Devices new metering ADE5xxx, ADE71xx, ADE75xx ADC/LCD/RTC/SPI/UART/16KF, LQFP64
Analog Devices ADSL Family: Eagle USB / Eagle II, Sold to Ikanos
ASIX AX11015 -- 128-512KF 32KR 3 UART TCP/IP and 10/100M Fast Ethernet MAC/PHY 80p 128p WiFi Dual Core
Atmel AT89LP 20MIPs 1T AT89LP2052/LP4052/213/214/216/51/52/828/6440, 14/20/28/32/40/44 pins
Atmel - AT89LP51/AT89LP52 wide Vcc AT89S51/S52/S8253
Austria Microsystems - Single phase metering, 24K/32K code, 1K ram, 80/96 LCD
Burr-Brown (ti) MSC12xx: 24b ADC /16b DAC + 8 MIPS 80C52, 4K-32KF, 1280RAM, 32bit AVG... 36QFN, TQFP48, TQFP64
Broadcom - Bluetooth Mouse/Kbd device, ROM + 20K RAM + 8K Flash 80C51 core
Caltech research paper, covers Async 80C51 core, very low power, pJ/instruction
Chesen CSC1000 USB-OTG, also CSC6x58 USB 12MBd / UART
CEL ZigBee Transceivers ZIC2410 2.4GHz 96KF 8KR
Chipcon (now TI) CC1010 : 300..1000 MHz RF Transceiver + 32KF/2KR/ADC TurboC51 TQFP64
Chipcon ZigBee CC2430 series 32KF 64KF 128KF 8KR 7mm package Lw Pwr modes TurboC51
Chipswinner CW89FExx 16/20/24/28/32/40/44pin, EEPROM,3.3-5.5V
Chipswinner CW89Exx 40/44pin, 8KF/6KF
Chipswinner CW99SC69 32-Bit Cortex-M3 + 8052 Core MCU (?)
CML 80C51+Modem (ext code) lqfp100
Controlchips P-51, ISA/PC104 Port, 4K DPRam, 8K ISA Bootable Code RAM; also USB-RAM
Coreriver(Gencore), TurboCored small devices 8/14/16/20 pins 28/40/44pins 40/44/64/80/100 pins Flash & OTP
Coreriver(Gencore), Midas V2.1 - 24/28/32 Wide Vcc 7KF FLASH 89C51+ADC/PWM
Cypress USB uC EZ_USB, EZ-USB-FX, EZ-USB-FX2, ATA USB1 & USB2.0, RAM Based C51, PSoC3
Cypress PSoC3 Turbo8051+CPLD+CAN+USB+ADC Wide Vcc
CYROD 89C51 3.3 & 5V 20p-64p 12T, 6T, 1T, MDU, SPI, i2c, ADC,
CYROD Product Selector, 20p-64p
DallasSemi (Maxim) Turbo Core Pioneers, 87C5xx/80C390/80C400/89C4x0/MAX7651/DS5240
DallasSemi DS80C400, 18.75 MIPS, Ethernet/CAN/UARTx3/16MB Address TCP/IP ROM 100tqfp
DcD Digital Core Design DT8051 (etc) IP core / Debug included
Dolphin 80C51 variants IP cores, family of enhanced 8051
Dolphin Flip80251 IP core, enhanced 80251, (originally Intel & Temic), SW tools proven
Domosys - Power Line Modems, 64KF, 6KRAM, TurboFLASH (custom)
Domosys - June 2002, U-Chip with Whirl8051 Core (+DSP) 25x
EM Microelectronics FLASH based 80C51 smart cards
Emosyn [SST] C51 cored Smart card chips from 37c/100K
Fairchild Motor Controller 12KF 1KR TQFP32 ADC/SPI/i2c/UART PWM/AMC
Finechips (ABOV assoc) Products list
FTDI FT51 48MHz/ADC/DAC/SPI/6MBd UART/Multiple USB/USB DFU bootloader/24p,32p,44p,48p
GENESYS GL711FW ATA/ATAPI <->IEEE1394, GL816 FlashCard <-> USB 2.0, GL814
Goal Semiconductor - Now Ramtron
Greenchips Applications processors, includes 89Cxx ex Magnachip
HandShake Solutions Async Core, high speed, with low EMC, and low pJ/Instruction
Hunan HoChip Multi-Thread 8051 variants, 2 or 3 threads, 40MHz
Hunan HoChip LSx151 20p 2/4/8K 3 Threads 1.8-5.5V SPI/i2c/UART ADC
Hunan HoChip LS151A family table
Hunan HoChip LS052A Triple Core/Thread 40/48 pins 1.8-5.5V to 64KF/16KR 40MHz
Hunan HoChip LS052A family table
Hunan HoChip LS2051/LS4051 20p variants (Dual Core/Thread)
Holtek HT85F2230..HT85F2280 2.2-5.5V, 25MHz, 12b ADC, DAC, 16/20/24/28/48/64 pins
Honeywell SSEC - High Temp (300 degC ) Products, Mask 83C51FX
Infineon (Siemens) - CAN, ADC, USB, C508, C868 etc, Strong OTP families
Infineon FLASH XC800 family, includes new 20p XC864, and 64K XC878
Infineon new XC800 Turbo cored FLASH & on Chip DEBUG family, Indust./Automotive Spec. One Euro+
XC878 52/64KF.ECC TQFP64 3.3 & 5V, ADC, PWM CoPro 85'C and 105'C CAN/LIN from e1,5@10K
Easy Kit XC878 e99, USB Flash PGM, Unlimited Debugger CAN/LIN
Infineon PMA71xx Series ASK/FSK Sub 1GHz ISM, 32kBd, with 8051: 6KF 256R TSSOP38
Infineon TLE983x uC+Power LIN ADC VREG 36-64KF PowerSW VQFN-48
Infineon SLE76 series 80251 core, AES block smart cards, extended Temp, SLM76CF5120P etc
IR Asym Dual Core Motor Control Overview
IR IRMCx341 Asym Dual Core Motor Control OTP and RAM choices, 120MHz PLL 30 MIPS
Intel - originator of MCS51, 51FX, MCS151, MCS251 cores
ICSI - Stds FLASH/ROM 89C51,C52,C54,C58,C64,E64,
ICSI ASP_C51 IC1100 USB/MP3.PCMCIA, IC9000 Bluetooth, IC3101 Camera+FuC+USBh
ISSI - FLASH and ROM {?}
Jaalaa - 27MHz Wireless Cordless Keyboard/Mice link solutions 80C51 core,
Macronix - MX10C805X ISP/PWM, MX10F20xFC LCD 100p, MX10FMAX, [ MX10EXA ]
MangaChip (Hynix) - see Greenchip
MangaChip Smart Cards Turbo 80C52 core - see Greenchip
Megawin, 40/44p 4KF..64KF with ADC, 24/48MHz, & 10p/20p/28/40/44/48/64P 1T core 2051/4051/6051
Megawin, USB 16K/64KF Flash, Full Speed 48p/64p
Maxim (Teridian) Metering Systems. Low cost 8K+ LCD 20b ADC
Micronas - easyLIN 12V IO and 12V power
Microtune MT0780, - 2.4GHz BlueTooth/USB/Codec, with 64KF,4KR, FLASH C51's
M-Square MS8951 MS89F51 64KF+32KDF, 6 bit ADC, 3.3:1.8VReg, TQFP48 PLCC44 [SOJ28 SSOP28 DIP20 DIP18 SOP8?]
MyMS 8051 Smart cards, Flash and EE
Myson 8051 FLASH 8..256KF, Monitor, Ethernet, 28-128p GP CS8958, CS8954, CS8960, CS8966, etc
Myson CS6208 Ethernet 128p CS6209 128KF 128p 10/100 Ethernet
Nordic Semi nRF24LE1 OTP/Flash ULP wireless 2.4GHz
Nuvoton(Winbond) W78Exx, W77Exx, W79Exx, and LPC series 80C51 families
Nuvoton(Winbond) Alternate 8051 LPC and 40/44 pin Variants web
Nuvoton 8051 family Selection guides, WEB based, includes N76E884/N76E885 1T 8KF/18KF 512R 22MHz
Nuvoton(Winbond) MO51 family, Wide Vcc Cortex M0 (32 bit) with 8051 External Memory interface
Nuvoton N76E884/N76E885 1T 8KF/18KF 512R 22MHz IRC, i2c, SPI, UART, BSL, KBI, ADC, PWM, BOR MSOP10/TSSOP16/TSSOP28/SOP28
NXP(Philips) - LPC Series Flash 1K-16K ADC, LPC98x/LPC97x new wide supply variants
NXP(Philips) 80C51 Flash 3V & 5V i2c Standard 40/44pin 8051's
NXP(Philips) 80C51 and ARM core Microcontrollers, Arm7, Arm9, Cortex M3, M0, M4, Dual Core
PLX USB 2.0 Devices NET2282 40MBps sustained speeds on 480Mbps USB
Prolific PL8331/PL8332/PL8333 Energy Meter 64KF 2KR 64p/80p/128p LCD 24b ADC/UARTs/RTC/I2C/SPI/48gpio 2.4V to 5V
Prolific PL-25A1 Hi-Speed USB Host-to-Host bridge controller
Q80C51 QuickCore (SoftCPU - FPGA) Single/Multi Turbo 8051uC+DBG for FPGA families {?}
Ramtron (Goal) Std & Mixed signal Flash C51's - 40 MIPS and FRAM-Enhanced devices
RDC, Taiwan - RISC 8051 IP cores, RISC 80C186 (+Ethernet) devices
Silicon Motion USB2.0 Flash Disk controller : SLC & MLC NAND type Flash, 33MB/s Rd
Samsung S3FI1BG 384KF 4KR USB/SPI/UART/ADC/LCD/RTC/PWM/ADPCM 24MHz 80TQFP
Sensor Platforms SSP1492 - 80pin 14 MIPs with Cordic and ALU
SIDSA FIPSOC Risc 8051 & Configurable Logic & Analog Cells (Custom/IP?)
Siliconians - Spread Spectrum, & Flash
SiLabs - Mixed Signal, ADC/DAC/PWM/SPI/CAN/USB High Performance, Small!, to 100MIPS.3V
SiLabs new 2mm/3mm/4mm/5mm packages 1.5K to 16KF 25-100 MIPS C8051F85x low cost
Silicon Laude - Dual Core, Secure 80C51, optimised for MRAM
sinowealth SH79xx 20p-100p SH79F081/SH79F161/SH79F166/SH79F168
SMSC - Arcnet C52's, Keyboard controllers, System IO
SMSC - LPC47x family SuperIO, some with 64K Flash 80C52; USB97C201 USB2.0 480MBd
SMSC - KBC1122P - Mobile KBC with SFI, ADC, & DAC, IrDA V1.2 (4Mbps), LPC, 102 i/o
SMSC - Automotive Grade HighSpeed USB 48/64 pins
SSTI - FLASH, SST89C54, C58, x554,x564 PCA, SPI, 3V, 5V, new RD2 cores 8KF..64KF, PCA
SST79LF008 - Mobile Platform Controller 2KR 128KF 8Mb LPC Keyboard/Fan/ADC/DAC tqfp176
ST's uPSD - uPSD3400 : 96-290KF/4-8KR/12MBd USB/ADC/JTAG/ISD/PLD/i2c/2UART/IrDA/PWM/ISD 80p/52p
STC, 16/20/28/32/40/44 pin std pinouts, 2/4/6/8/16/32/64K devices, with ADC, 35MHz 1T
Google Translate version of above, gives device release dates etc
STC more English distribution site
STC #1 English Data and Parts Ordering website 8/16/20/28/32/44/48 pin ADC/PCA/RcOSC/EE 1 Cycle(pk) core 35MHz FLASH
STC #2 English Parts Ordering website 8/16/20/28/32/44/48 pin ADC/PCA/RcOSC/EE 1 Cycle(pk) core 35MHz FLASH
SYNCMOS, FLASH SM894051C,SM89xx, SM79xx, SM59xx, 1T: SM39Rxx,SM59Rxx, 10MSOP thru 64TQFP
SYNCMOS, Selector Guide, PDF Table, and News Releases
Syntek 6031/6011/6012/6057 FLASH 89C51 LCD monitor etc ADC PWM 20/28/40/42/44/48p
Syntek STK6031/32/33/37/516 FLASH 89C51 8/16/64K DIP16/SOP16/TSSOP20/Dip20/40/44/48p
Tekmos, Legacy replacements, Intel, Philips etc: (8KF-64KF) 87C751, 87C51RC, 89C668
Teridian (TDK) - C52 Modems, C51+ISA Slave, Smart Card, Advanced metering - Now Maxim.
Tezzaron - 3D Stacked FastSRAM to 512KBytes and 1 Cycle 80C51, 200MIPs 100MFLOPS
TI : Precision MSC12xx, and USB & 1394 devices with 8052 cores
TI TUSB6250 - USB 2.0 to ATA/ATAPI / 30 MIPs 8052 core 44K RAM
TI TUSB3410 RS232(921K)/IrDA(115K) Low Cost Serial-to-USB Converter 8052Core16K+2K RAM, DMA, LQFP32
Triscend - TurboC51 + RAM FPGA {RIP?}
Trumpion - USB, MP3, MMC interfaces, Flash Consumer variants
ULI M9205 USB 2.0 Video/Audio Device Controller
Winedge, FLASH/OTP/Mask, Pagers & Low Voltage Turbo51's
WizNET 8051 Hardwired TCP/IP stack 10/100 Ethernet PHY 64KF 64KR TQFP100
Zensys Mixed Signal RF and 80C51 ~900MHz Transciever, 20KuF
Zilog Z8051 Z51Fxx 10p-80p, 4KF-64KF, EEPROM, 2T core, 12b ADC, 1.8-5.5V, up to 4 UART,
Zilog Evaluation Kits incl OCD debug, for Z51F0410,Z51F0811,Z51F3220,Z51F3221,Z51F6412

If these links fail due to future changes, start from the vendors home page.
E&OE.

80C51 Core Variants Overview
The widest horsepower range of ANY uC. Period.