EFM8 Busy Bee Family
EFM8BB3 Data Sheet
The EFM8BB3, part of the Busy Bee family of MCUs, is a per-
formance line of 8-bit microcontrollers with a comprehensive ana-
log and digital feature set in small packages.
These devices offer state-of-the-art performance by integrating 12-bit ADC, internal
temperature sensor, and up to four 12-bit DACs into small packages, making them ide-
al for general purpose applications. With an efficient, pipelined 8051 core with maxi-
mum operating frequency at 50 MHz, various communication interfaces, and four chan-
nels of configurable logic, the EFM8BB3 family is optimal for many embedded applica-
tions.
EFM8BB3 applications include the following:
• Consumer electronics
• Precision instrumentation
• Power management and control
• Industrial control and automation
• Smart sensors
• Automotive control
KEY FEATURES
• Pipelined 8-bit 8051 MCU Core with
50 MHz operating frequency
• Up to 29 multifunction I/O pins
• One 12-bit/10-bit ADC
• Four 12-bit DACs with synchronization
and PWM capabilities
• Two low-current analog comparators with
built-in reference DACs
• Internal temperature sensor
• Internal 49 MHz and 24.5 MHz oscillators
accurate to ±2%
• Four channels of Configurable Logic
• 6-channel PWM / PCA
• Six 16-bit general-purpose timers
Core / Memory
CIP-51 8051 Core
(50 MHz)
Flash Program
Memory
(up to 64 KB)
Clock Management
External
Oscillator
High Frequency
49 MHz RC
Oscillator
High Frequency
24.5 MHz RC
Oscillator
Energy Management
Internal LDO
Regulator
Power-On Reset
RAM Memory
(up to 4352 bytes)
Debug Interface
with C2
Low Frequency
RC Oscillator
Brown-Out Detector
8-bit SFR bus
Serial Interfaces
2 x UART
SPI
High-Speed
I2C Slave
I/O Ports
External
Interrupts
General
Purpose I/O
Timers and Triggers
Timers
0/1/2/5
Watchdog
Timer
Analog Interfaces
ADC
2x
Comparators
Internal
Voltage
Reference
Security
16-bit CRC
Pin Reset
PCA/PWM
Timer 3/4
I
2
C / SMBus
Pin Wakeup
4 x Configurable Logic Units
Up to 4 x
Voltage DAC
Lowest power mode with peripheral operational:
Normal
Idle
Suspend
Snooze
Shutdown
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Rev. 1.2
EFM8BB3 Data Sheet
Feature List
1. Feature List
The EFM8BB3 device family are fully integrated, mixed-signal system-on-a-chip MCUs. Highlighted features are listed below.
• Core:
• Analog:
• Pipelined CIP-51 Core
• 12/10-Bit Analog-to-Digital Converter (ADC)
• Fully compatible with standard 8051 instruction set
• Internal temperature sensor
• 70% of instructions execute in 1-2 clock cycles
• 4 x 12-Bit Digital-to-Analog Converters (DAC)
• 50 MHz maximum operating frequency
• 2 x Low-current analog comparators with adjustable refer-
• Memory:
ence
• Up to 64 kB flash memory (63 kB user-accessible), in-sys-
• Communications and Digital Peripherals:
tem re-programmable from firmware in 512-byte sectors
• 2 x UART, up to 3 Mbaud
• Up to 4352 bytes RAM (including 256 bytes standard 8051
• SPI™ Master / Slave, up to 12 Mbps
RAM and 4096 bytes on-chip XRAM)
• SMBus™/I2C™ Master / Slave, up to 400 kbps
• Power:
• I
2
C High-Speed Slave, up to 3.4 Mbps
• Internal LDO regulator for CPU core voltage
• 16-bit CRC unit, supporting automatic CRC of flash at 256-
• Power-on reset circuit and brownout detectors
byte boundaries
• I/O: Up to 29 total multifunction I/O pins:
• 4 Configurable Logic Units
• Up to 25 pins 5 V tolerant under bias
• Timers/Counters and PWM:
• Selectable state retention through reset events
• 6-channel programmable counter array (PCA) supporting
• Flexible peripheral crossbar for peripheral routing
PWM, capture/compare, and frequency output modes
• 5 mA source, 12.5 mA sink allows direct drive of LEDs
• 6 x 16-bit general-purpose timers
• Clock Sources:
• Independent watchdog timer, clocked from the low frequen-
cy oscillator
• Internal 49 MHz oscillator with accuracy of ±2%
• On-Chip, Non-Intrusive Debugging
• Internal 24.5 MHz oscillator with ±2% accuracy
• Full memory and register inspection
• Internal 80 kHz low-frequency oscillator
• Four hardware breakpoints, single-stepping
• External CMOS clock option
• Pre-programmed UART bootloader
• External crystal/RC Oscillator (up to 25 MHz)
• Temperature range -40 to 85 ºC or -40 to 125 ºC
• Available in commercial, industrial, and automotive variants
With on-chip power-on reset, voltage supply monitor, watchdog timer, and clock oscillator, the EFM8BB3 devices are truly standalone
system-on-a-chip solutions. The flash memory is reprogrammable in-circuit, providing nonvolatile data storage and allowing field up-
grades of the firmware. The on-chip debugging interface (C2) allows non-intrusive (uses no on-chip resources), full speed, in-circuit
debugging using the production MCU installed in the final application. This debug logic supports inspection and modification of memory
and registers, setting breakpoints, single stepping, and run and halt commands. All analog and digital peripherals are fully functional
while debugging. Device operation is specified from 2.2 V up to a 3.6 V supply. Devices are AEC-Q100 qualified. Both G-grade and I-
grade devices are available in 4x4 mm 32-pin QFN, 3x3 mm 24-pin QFN, 32-pin QFP, or 24-pin QSOP packages. A-grade and addi-
tional I-grade devices are available in 5x5 mm 32-pin QFN and 4x4 mm 24-pin QFN packages. All package options are lead-free and
RoHS compliant.
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Rev. 1.2 | 2
EFM8BB3 Data Sheet
Ordering Information
2. Ordering Information
EFM8 BB3 1 F 64 G
–
A
–
QFN32 R
Tape and Reel (Optional)
Package Type
Revision
Temperature Grade G (-40 to +85), I (-40 to +125), A (-40 to +125)
Flash Memory Size – 64 KB
Memory Type (Flash)
Family Feature Set
Busy Bee 3 Family
Silicon Labs EFM8 Product Line
Figure 2.1. EFM8BB3 Part Numbering
All EFM8BB3 family members have the following features:
• CIP-51 Core running up to 49 MHz
• Three Internal Oscillators (49 MHz, 24.5 MHz and 80 kHz)
• SMBus
• I2C Slave
• SPI
• 2 UARTs
• 6-Channel Programmable Counter Array (PWM, Clock Generation, Capture/Compare)
• Six 16-bit Timers
• Four Configurable Logic Units
• 12-bit Analog-to-Digital Converter with integrated multiplexer, voltage reference, temperature sensor, channel sequencer, and direct-
to-XRAM data transfer
• Two Analog Comparators
• 16-bit CRC Unit
• AEC-Q100 qualified
• Pre-loaded UART bootloader
In addition to these features, each part number in the EFM8BB3 family has a set of features that vary across the product line. The
product selection guide shows the features available on each family member.
Table 2.1. Product Selection Guide
Digital Port I/Os (Total)
Comparator 0 Inputs
Comparator 1 Inputs
Pb-free (RoHS Compliant)
Ordering Part Number
Flash Memory (kB)
Voltage DACs
ADC0 Channels
Temperature Range
RAM (Bytes)
Package
QFN32-GI
QFP32
QFN24-GI
Rev. 1.2 | 3
EFM8BB31F64G-B-QFN32
EFM8BB31F64G-B-QFP32
EFM8BB31F64G-B-QFN24
64
64
64
4352
4352
4352
29
28
20
4
4
4
20
20
12
10
10
6
9
9
6
Yes
Yes
Yes
-40 to +85 °C
-40 to +85 °C
-40 to +85 °C
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