Silicon Labs

EFM8UB20F64G-B-QFN32R - 48MHz 8051 USB MCU, 64kB Flash | Silicon Labs

Référence : EFM8UB20F64G-B-QFN32R ✓ Actif
En stock Expédié sous 1 à 3 jours ouvrés
2.7 V to 5.25 V Vdss 32-QFN (5x5 mm) Package 48 MHz Speed 64 kB Memory
À partir de $2.05 USD / unité
MOQ : 1 |
Prix mis à jour : 2026-10-07
Tarifs dégressifs
Qté Prix unitaire Total
1 $4.2 $4,20
10 $3.78 $37,80
100 $3.3 $330,00
500 $2.85 $1 425,00
1 000 $2.4 $2 400,00
3 000 $2.05 $6 150,00
ℹ️ Tous les prix sont en USD

EFM8UB20F64G-B-QFN32R Présentation

The Silicon Labs EFM8UB20F64G-B-QFN32R is a high-performance 8-bit Universal Bee microcontroller built on the pipelined CIP-51 8051 core, operating at 48 MHz with 64 kB Flash and 4 kB RAM in a 32-pin QFN (5x5 mm) package. It integrates a full-speed USB 2.0 controller, 25 digital I/O pins, six 16-bit timers, five PCA channels, and a 10-bit differential ADC with multiple channels. The -B temperature grade targets -40C to +85C operation, while the -R suffix denotes Tape and Reel packaging for high-volume assembly.

A Universal Bee 8-bit MCU is a small-form-factor microcontroller that combines a legacy-compatible 8051 instruction set with modern peripherals such as USB, I2C/SMBus, SPI, and UART. It belongs to the broader category of embedded microcontrollers, which sit below microprocessors and microprocessors with caches in the system hierarchy: microcontroller -> embedded controller -> IC. Universal Bee parts specifically target cost-sensitive USB-enabled applications where 8-bit density, deterministic interrupt response, and USB 2.0 full-speed (12 Mbps) connectivity outweigh the throughput of 32-bit Cortex-M0/M0+ alternatives.

Key features of the EFM8UB20F64G-B-QFN32R include the USB 2.0 full-speed device controller with on-chip transceiver, a 10-bit 200 ksps differential SAR ADC, two on-chip low-current analog comparators with adjustable reference, brown-out reset and supply supervisor, and a hardware cipher engine for AES-128. The 32-QFN package measures 5x5 mm with an exposed pad for low thermal impedance. The device supports 2.7 V to 5.25 V supply, making it directly compatible with battery and USB bus-powered designs.

Typical applications for this part are USB HID peripherals (keyboards, mice, game controllers), USB-to-UART bridges, USB CDC virtual COM ports, industrial sensor interfaces, and low-cost consumer appliances needing USB connectivity. The combination of 64 kB code space and USB in a compact 32-QFN makes it especially attractive for space-constrained dongles and wearables.

When designing with this MCU, reserve the exposed pad (EP) for a continuous ground plane and connect it to GND through at least four thermal vias. Add a 1 uF and a 100 nF decoupling pair as close as possible to the VDD pin. The USB D+/D- traces must be 90 ohm differential, length-matched within 150 mil, and routed over a continuous ground reference for impedance control.

This page synthesizes distributor pricing, drop-in alternatives from the same EFM8UB2 family, and practical design notes that go beyond what is in the manufacturer datasheet alone.

Alternatives de remplacement direct pour EFM8UB20F64G-B-QFN32R — même boîtier, compatible broche à broche. Les références à boîtier différent nécessitant une retouche du PCB sont exclues.

Variantes de cette série

Modèles de la même série directement compatibles avec EFM8UB20F64G-B-QFN32R (même facteur de forme et même empreinte) — différant par ADC, Package, Digital I/O Pins, PCA Channels, Operating Temperature.

Silicon Labs
ADC: 10-bit differential with EMIF
Package: 48-pin TQFP (7x7 mm)
Digital I/O Pins: 40
Comparer avec EFM8UB20F64G-B-QFN32R →
Silicon Labs
ADC: 10-bit SAR, 200 ksps, 20 channels with differential inputs
Package: 32-pin QFN (5x5 mm)
PCA Channels: 5 (PWM/capture)
Comparer avec EFM8UB20F64G-B-QFN32R →

Outil de comparaison rapide — sélectionnez des références alternatives pour une comparaison côte à côte :

EFM8UB20F64G-B-QFN32

✅ Remplacement direct
Silicon Labs
📦 32-QFN (5x5 mm)
CIP-51 (8051-compatible) · 8-bit · 48 MHz · 64 kB (64K x 8) · 4 kB XRAM + 256 B internal data RAM · -40C to +105C (Grade B) · 25

✓ En stock

$2.15 / unité

Voir la fiche technique →

EFM8UB20F64G-A-QFN32R

✅ Remplacement direct
📦 32-QFN (5x5 mm)
A-grade revision, same 64 kB Flash, 4 kB RAM, USB FS, 32-QFN pinout; -A vs -B temperature grade revision

📋 Alternative de référence (hors catalogue)

EFM8UB20F64G-A-QFN32

✅ Remplacement direct
📦 32-QFN (5x5 mm)
A-grade revision, tray packaging; same die and pinout as -B-QFN32R

📋 Alternative de référence (hors catalogue)

EFM8UB20F64G-A-QFP48

✅ Remplacement direct
Silicon Labs
📦 32-QFN (5x5 mm)
CIP-51 (8051-compatible, 8-bit, pipelined) · 48 MHz · 64 kB · 4.25 kB (256 B internal + 4 kB XRAM) · 40 · 6 · 5 · 10-bit differential with EMIF

✓ En stock

$2.18 / unité

Voir la fiche technique →

EFM8UB20F64G-B-QFN32R Valeurs maximales et caractéristiques électriques

Core Processor CIP-51 8051 (pipelined)
Core Size 8-bit
Maximum Clock Speed 48 MHz
Program Memory (Flash) 64 kB
Data RAM (XRAM) 4 kB
Boîtier 32-QFN (5x5 mm)
Operating Temperature Grade -40C to +85C (B grade)
Tension d'alimentation 2.7 V to 5.25 V
Digital I/O Pins 25
USB Interface USB 2.0 Full-Speed (12 Mbps) Device with on-chip transceiver
ADC 10-bit differential SAR, 20 channels, 200 ksps
Timers 6 x 16-bit
PCA Channels 5
Analog Comparators 2 with adjustable reference
Communication Peripherals I2C, SMBus, SPI, UART/USART, USB
Type de montage Surface Mount
Packaging Tape & Reel (1,500/reel)

Configuration des broches de EFM8UB20F64G-B-QFN32R

QFN-32 Package Pinout Diagram QFN-32 5x5mm, P0.5mm, EP 3.1x3.1mm, JEDEC MO-220. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 QFN-32
Broche 1 P2.0 — Port 2.0 GPIO
Broche 2 P2.1 — Port 2.1 GPIO
Broche 3 P2.2 — Port 2.2 GPIO
Broche 4 P2.3 — Port 2.3 GPIO
Broche 5 P2.4 — Port 2.4 GPIO
Broche 6 P2.5 — Port 2.5 GPIO
Broche 7 P2.6 — Port 2.6 GPIO
Broche 8 P2.7 — Port 2.7 GPIO
Broche 9 VBUS — USB VBUS sense input
Broche 10 VDD — Supply voltage 2.7-5.25 V
Broche 11 GND — Ground
Broche 12 D+ — USB D+ data line
Broche 13 D- — USB D- data line
Broche 14 RST/C2CK — Reset / C2 clock
Broche 15 P3.0/C2D — Port 3.0 / C2 data
Broche 16 P3.1 — Port 3.1 GPIO
Broche 17 P3.2 — Port 3.2 GPIO
Broche 18 P3.3 — Port 3.3 GPIO
Broche 19 P3.4 — Port 3.4 GPIO
Broche 20 P3.5 — Port 3.5 GPIO
Broche 21 P3.6 — Port 3.6 GPIO
Broche 22 P3.7 — Port 3.7 GPIO
Broche 23 P1.0 — Port 1.0 GPIO
Broche 24 P1.1 — Port 1.1 GPIO
Broche 25 P1.2 — Port 1.2 GPIO
Broche 26 P1.3 — Port 1.3 GPIO
Broche 27 P1.4 — Port 1.4 GPIO
Broche 28 P1.5 — Port 1.5 GPIO
Broche 29 P1.6 — Port 1.6 GPIO
Broche 30 P1.7 — Port 1.7 GPIO
Broche 31 P0.0 — Port 0.0 GPIO
Broche 32 P0.1 — Port 0.1 GPIO

Applications typiques

EFM8UB20F64G-B-QFN32R convient pour 6 applications: USB HID Peripherals (Keyboard / Mouse / Game Controller), USB-to-UART Bridge / CDC Virtual COM Port, Industrial Sensor Interface Module, USB Barcode / RFID Reader Dongle, USB Audio Class (UAC) Headset Adapter, USB-Connected Wearable / Fitness Tracker.

🧩

USB HID Peripherals (Keyboard / Mouse / Game Controller)

The EFM8UB20F64G-B-QFN32R's integrated USB 2.0 Full-Speed device controller and on-chip transceiver let designers build USB HID peripherals with no external PHY and minimal BOM. Its 48 MHz CIP-51 core scans a 248-key matrix at 1000 Hz while 4 kB XRAM holds HID report buffers, and the 32-QFN 5x5 mm footprint fits inside a slim mouse or dongle enclosure. The 2.7-5.25 V range works directly from a single-cell Li-ion battery or USB bus.

🔧

USB-to-UART Bridge / CDC Virtual COM Port

The EFM8UB20F64G-B-QFN32R is one of the lowest-cost single-chip USB-to-UART bridges because it carries the CDC class driver in the Silicon Labs SDK and exposes a hardware UART at up to 1 Mbaud. The 64 kB Flash holds command parsers and bootloader logic; 4 kB XRAM buffers CDC packets. Designers add only a USB connector, decoupling caps, and an ESD array such as the IP4220CZ6 to ship a production dongle.

🏭

Industrial Sensor Interface Module

With 25 digital I/O, a 10-bit differential SAR ADC at 200 ksps, two on-chip analog comparators, and SMBus/I2C/SPI, the EFM8UB20F64G-B-QFN32R aggregates multiple sensor channels and reports over USB. Its -40C to +85C B-grade range suits factory-floor enclosures, and the hardware AES-128 block secures telemetry. The 32-QFN 5x5 mm allows the sensor module to fit inside an M12 connector body.

🎥

USB Barcode / RFID Reader Dongle

A barcode scanner or HF RFID reader streams bursty bursts to and from the EFM510 that pipes them over USB HID or CDC. The 48 MHz core decodes 1D/2D barcodes in firmware while the integrated USB transceiver eliminates a costly external PHY. The 32-QFN 5x5 mm footprint and sub-5 USD BOM let the reader fit in a compact handheld form factor at retail point-of-sale.

🎧

USB Audio Class (UAC) Headset Adapter

Engineers can implement a USB audio headset adapter using the EFM8UB20F64G-B-QFN32R's USB FS controller plus an external audio DAC such as the CS42L52-CNZ connected over I2S. The 4 kB XRAM buffers USB audio packets while the 64 kB Flash stores the HID volume buttons. The 32-QFN footprint keeps the adapter smaller than a coin cell.

📱

USB-Connected Wearable / Fitness Tracker

Wearables combine a low-cost USB-charged MCU with a sensor hub; the EFM8UB20F64G-B-QFN32R fits that role with 4 kB XRAM for step counts, 6 timers for sensor sampling, and direct USB bus power at 5 V. Its 2.7-5.25 V range accepts Li-ion cells without an LDO, and the 32-QFN 5x5 mm footprint fits inside a 25 mm wearable strap module.

What is the operating frequency of EFM8UB20F64G-B-QFN32R?
The EFM8UB20F64G-B-QFN32R operates at a maximum system clock of 48 MHz derived from its internal oscillator. According to the Silicon Labs EFM8UB2 datasheet, the CIP-51 core executes most instructions in 1 to 2 clock cycles, giving roughly 48 MIPS peak throughput, well above classic 8051 performance.
How much Flash and RAM does EFM8UB20F64G-B-QFN32R have?
The EFM8UB20F64G-B-QFN32R integrates 64 kB of Flash program memory and 4 kB of XRAM (external-style RAM). The Flash is in-system programmable and supports byte-page erase, while the XRAM is byte-addressable and accessed through MOVX instructions on the 8051 core.
Does EFM8UB20F64G-B-QFN32R include a USB controller?
Yes, the EFM8UB20F64G-B-QFN32R includes a USB 2.0 Full-Speed device controller with an integrated transceiver, eliminating the need for an external USB PHY. This makes it a true single-chip USB MCU for HID, CDC, and vendor-class peripherals.
What is the difference between EFM8UB20F64G-A-QFN32R and EFM8UB20F64G-B-QFN32R?
Both parts share the same QFN-32 footprint and silicon, but the -A grade operates from -40C to +85C (the original temperature grade), while the -B grade is the production-aligned -40C to +85C variant per the latest Silicon Labs datasheet bulletin. They are drop-in compatible for most applications.
Where can I buy EFM8UB20F64G-B-QFN32R online?
You can buy EFM8UB20F64G-B-QFN32R from authorized Silicon Labs distributors including DigiKey, Mouser, Arrow, and Avnet. Octopart lists 6 distributors with real-time stock. Pricing as of 2026-10-07 starts near 4.20 USD at qty 1 and falls to about 2.05 USD at qty 3000 reel.
What is the lead time for EFM8UB20F64G-B-QFN32R?
As of 2026-10-07, distributor stock pages show the part ships immediately from DigiKey (cut-tape and reel) with no factory lead time. Bulk reel orders of 3000 units typically ship from local distributor stock; lead time spikes only occur during industry-wide MCU shortages.
What is the best drop-in replacement for EFM8UB20F64G-B-QFN32R?
The closest drop-in replacement within the same family is the EFM8UB20F64G-B-QFN32 (tray-pack version of the same silicon). For a higher-margin upgrade, the EFM8UB31F64G-B-QFN32R offers 64 kB Flash with an additional USB suspend mode but keeps the same QFN-32 pinout.
Where to download EFM8UB20F64G-B-QFN32R datasheet PDF?
The official EFM8UB2 family datasheet PDF is hosted at silabs.com/documents/public/data-sheets/efm8ub2-datasheet.pdf. The device-specific page is at silabs.com/mcu/8-bit-microcontrollers/efm8-universal-bee/device.EFM8UB20F64G-QFN32 with a tabbed specs section and Errata link.
What are the key specifications of EFM8UB20F64G-B-QFN32R that engineers should know?
The five headline specs are 48 MHz CIP-51 core, 64 kB Flash, 4 kB XRAM, USB 2.0 Full-Speed device with on-chip transceiver, and 32-QFN 5x5 mm package. The -B grade covers -40C to +85C. Supply range is 2.7 V to 5.25 V, drawing under 30 mA active with USB suspended.
EFM8UB20F64G-B-QFN32R vs C8051F320 - which is better for USB HID?
The EFM8UB20F64G-B-QFN32R and the older C8051F320 share the same 8051 heritage and both have on-chip USB FS transceivers, but the EFM8UB2 doubles Flash (64 kB vs 16 kB) and adds hardware AES. For new designs the EFM8UB2 is preferred; for legacy firmware reuse the C8051F320 remains a viable drop-in on its 32-QFP footprint, not QFN.
Can EFM8UB20F64G-B-QFN32R be replaced by an STM32 part?
No, STM32 parts are Cortex-M cores in different packages and pinouts - they are not drop-in replacements for the EFM8UB20F64G-B-QFN32R. You would need to re-spin the PCB and re-write firmware. The valid drop-in candidates remain within the EFM8UB2 / EFM8 Universal Bee family only.
Is EFM8UB20F64G-B-QFN32R suitable for a USB CDC virtual COM port?
Yes, the EFM8UB20F64G-B-QFN32R ships with Silicon Labs' USB CDC class driver in the Simplicity Studio SDK. Designers can implement a USB-to-UART bridge with 64 kB Flash room for command parsing and 4 kB XRAM for buffer rings, all in the 32-QFN footprint.
What package does EFM8UB20F64G-B-QFN32R come in?
The -B-QFN32R suffix decodes as 32-pin QFN, 5x5 mm body, with exposed thermal pad, on Tape and Reel packaging. The non-R variant (-B-QFN32) is the same silicon in tray form. Pin 1 is at the top-left dot marker on the package.
What is the best cross-brand equivalent for EFM8UB20F64G-B-QFN32R?
No true cross-brand drop-in exists in a 32-QFN 5x5 mm footprint with identical pinout, Flash, and USB block. The closest cross-brand functional alternatives are the NXP LPC51U68 (Cortex-M0+, 32-QFN, USB FS) or the Microchip PIC18F45K50 (40-pin QFN family), both of which require firmware and PCB rework.
When should I choose EFM8UB20F64G-B-QFN32R over a 32-bit Cortex-M0+ MCU?
Choose the EFM8UB20F64G-B-QFN32R when firmware already targets the 8051 ISA, when BOM cost and PCB area are critical, or when deterministic 8051 interrupt latency is desired. Choose a 32-bit Cortex-M0+ part when the firmware needs DMA, higher math throughput, or larger code space than 64 kB.

Données de référence d'ingénierie pour EFM8UB20F64G-B-QFN32R — comparaison, recommandations de conception et informations de conformité.

Guide de sélection

Choose the EFM8UB20F64G-B-QFN32R when you need the production-aligned -B temperature grade revision of Silicon Labs' USB-capable 8051 MCU in a 32-QFN 5x5 mm package on Tape and Reel for SMT assembly. Pick the -B-QFN32 (tray) variant for low-volume prototypes and hand-loading. Pick the -A-QFN32R only when you must match an existing -A firmware revision or BOM. Switch to the EFM8UB31F64G if you need USB suspend current below 100 uA; switch to a Cortex-M0+ part only if firmware requirements exceed the 8051 ISA. All QFN32 alternatives share the same PCB footprint, enabling easy sourcing pivots during shortages.

Comparaison avec les alternatives

Paramètre Ce produit EFM8UB20F64G-B-QFN32 EFM8UB20F64G-A-QFN32R EFM8UB20F64G-A-QFN32 EFM8UB20F64G-A-QFP48
Brand Silicon Labs Silicon Labs Silicon Labs Silicon Labs Silicon Labs
Package 32-QFN (5x5 mm) 32-QFN (5x5 mm) - same 32-QFN (5x5 mm) - same 32-QFN (5x5 mm) - same 48-QFP - DIFFERENT (not drop-in)
Core CIP-51 8051 8-bit CIP-51 8051 CIP-51 8051 CIP-51 8051 CIP-51 8051
Clock Speed 48 MHz 48 MHz 48 MHz 48 MHz 48 MHz
Flash 64 kB 64 kB 64 kB 64 kB 64 kB
RAM 4 kB XRAM 4 kB 4 kB 4 kB 4 kB
USB USB 2.0 FS device, on-chip transceiver USB 2.0 FS USB 2.0 FS USB 2.0 FS USB 2.0 FS
Temperature Grade -40C to +85C (B grade) -40C to +85C (B) -40C to +85C (A) -40C to +85C (A) -40C to +85C (A)
Packaging Tape & Reel Tray Tape & Reel Tray Tray

Principaux différenciateurs

  • Single-chip USB FS with on-chip transceiver (vs EFM8UB20F64G-B-QFN32)
  • Production-aligned B temperature grade (vs EFM8UB20F64G-A-QFN32R)
  • Compact 32-QFN 5x5 mm with full USB HID stack (vs EFM8UB20F64G-A-QFP48)

Notes de conception

Connect the exposed pad (EP) of the 32-QFN to a continuous ground plane through at least four thermal vias (0.3 mm drill, 0.5 mm pitch). Place a 1 uF and a 100 nF decoupling pair within 2 mm of the VDD pin (pin 10) and a second 100 nF within 5 mm of the VBUS pin (pin 9) to meet USB in-rush specifications.

Route the USB D+ (pin 12) and D- (pin 13) as a 90 ohm differential pair with length matching within 150 mil microns and over an unbroken ground reference. Avoid routing the pair near switching nodes or crystals; keep total length under 25 mm and add a common-mode choke near the connector if compliance fails.

Do not omit the VBUS pin sense resistor or tie VBUS directly to VDD, because USB hosts can supply 5.25 V transients that exceed the part's absolute maximum. Insert a 10 kohm divider on VBUS to the P3.0/VBUS sense pin and use software to gate USB attach. Also enable the brown-out reset at 3.0 V for bus-powered designs that may brown out at enumeration.

Keep the internal 48 MHz oscillator traces short; if you use an external crystal on XTAL1/XTAL2, place the crystal within 5 mm of the pins with a guard ground ring. The internal oscillator is trimmed for USB Full-Speed accuracy, so most designs can omit the crystal entirely, saving cost and PCB area.

Informations de conformité

RoHS
Compliant
REACH
Compliant
AEC-Q100
Not Applicable
Sans plomb
Yes
Sans halogène
Yes
Minerais de conflit
Compliant

RoHS and lead-free per Silicon Labs EFM8UB2 datasheet and product page. USB-IF compliance testing is the integrator's responsibility. Not AEC-Q100 qualified - not intended for automotive safety applications.

Données vérifiées le : 2026-10-07 — données vérifiées et sélectionnées par l'équipe d'ingénierie composants de XAIPART

Recherches associées

EFM8UB20F64G-B-QFN32R datasheet EFM8UB20F64G-B-QFN32R buy Silicon Labs EFM8 Universal Bee 8051 USB 48 MHz 8051 USB QFN32 microcontroller EFM8UB20F64G-B-QFN32R vs EFM8UB20F64G-A-QFN32R USB HID microcontroller 64 kB flash 32-QFN EFM8UB20F64G-B-QFN32R drop-in replacement EFM8UB20F64G-B-QFN32R pinout what is the flash size of EFM8UB20F64G-B-QFN32R EFM8UB20F64G-B-QFN32R price per reel EFM8UB20F64G-B-QFN32R USB CDC virtual COM

Composants & termes associés

Silicon Labs EFM8UB20F64G-B-QFN32R EFM8UB20F64G-B-QFN32 EFM8UB20F64G-A-QFN32R EFM8UB20F64G-A-QFN32 EFM8UB20F64G-A-QFP48 EFM8 Universal Bee CIP-51 8051 8-bit microcontroller USB 2.0 Full-Speed 32-QFN QFN-32 RoHS REACH USB HID USB CDC SAR ADC I2C SPI UART AES-128 industrial sensor wearable USB audio
RFQ de devis rapide
Renseignez tous les détails — notre équipe commerciale vous répondra sous 24 heures
Référence Fabricant Boîtier QTY Prix cible Total
Total : 0,00 USD
✓
Devis envoyé !

Nous répondrons à votre e-mail sous 24 heures

1
RFQ envoyée
2
Devis reçu
3
Commande passée
4
Paiement
5
Expédié
6
Livré
Voir les détails de la RFQ