Silicon Labs EFM8BB51 & EFM8BB52 Busy Bee 8-Bit MCUs

Silicon Labs EFM8BB51 and EFM8BB52 Busy Bee MCUs are multi-purpose microcontrollers with a comprehensive feature set in compact packages. These devices offer high value by integrating advanced analog and communication peripherals into a small footprint, making them ideal for space-constrained applications. With an efficient 8051 core, 5V capable I/O, precision analog, and enhanced pulse-width modulation, the EFM8BB51 and EFM8BB52 MCUs are optimal for embedded applications.

The Silicon Labs EFM8BB51 and EFM8BB52 Busy Bee MCUs include on-chip power-on reset, a voltage supply monitor, a watchdog timer, and an integrated clock oscillator. The Flash memory is re-programmable in-circuit, providing nonvolatile data storage and allowing field upgrades of the firmware. The on-chip debugging interface (C2) allows non-intrusive (uses no on-chip resources) 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.

The EFM8BB51 MCU is offered in 20-pin TSSOP and QFN packages. The device is specified for 1.8V to 5.5V operation. The EFM8BB52 MCU is available in 20-pin and 28-pin QFN packages or a 24-pin QSOP package. The device is specified for 2.2V to 3.6V operation or up to 5.25V with the 5V regulator option. All package options are lead-free and RoHS compliant.

Features

Core
- Pipelined CIP-51 Core
- Fully compatible with standard 8051 instruction set
- 70% of instructions execute in 1-2 clock cycles
- 50MHz maximum operating frequency
Memory
- Up to 16kBFlash memory, in-system re-programmable from firmware.
- EFM8BB51: Up to 1280 bytes RAM
- EFM8BB52: Up to 2304 bytes RAM
Power
- EFM8BB51: 8.0V to 5.5V single power supply
- EFM8BB52: 2.2V to 3.6V or 3.0Vto 5.25V single power supply
- 5V input LDO regulator (EFM8BB52 only)
- Internal LDO regulator for CPU core voltage
- Power-on reset circuit and brownout detectors
- Snooze mode with LFO running, 10µA and 30µs wake
I/O:
- EFM8BB51: 16 total multifunction I/O pins
- EFM8BB52: Up to 22 total multifunction I/O pins
- All pins 5V capable under bias
- Flexible peripheral crossbar for peripheral routing
- High current to allow the direct drive of LEDs
- 5mA source, 12.5mA sink allows the direct drive of LEDs (EFM8BB52 only)
Clock sources
- Internal 49MHz oscillator
- Internal 24.5MHz oscillator (EFM8BB52 only)
- Internal 80kHz low-frequency oscillator
- Internal 10MHz oscillator (EFM8BB51 only)
- External CMOS clock option
On-chip, non-intrusive debugging
- Full memory and register inspection
- Four hardware breakpoints, single-stepping

Timers, counters, and PWM
- 3-channel programmable counter array (PCA) supporting PWM, capture/compare, and frequency output modes
- 3-channel PWM engine with complementary outputs and dead time insertion (DTI)
- 2x 8-bit general-purpose timers (EFM8BB51 only)
- EFM8BB51: 4x 16-bit general-purpose timers
- EFM8BB52: 5x 16-bit general-purpose timers
- Independent watchdog timer, clocked from the low-frequency oscillator
Communications and digital peripherals
- 2x UART up to 3Mbaud
- SPI Main / Secondary up to 12Mbps
- SMBus™/I²C Leader / Follower up to 400kbps
- 16-bit CRC unit, supporting automatic CRC of flash at 256-byte boundaries
Analog
- 12-bit, 612ksps Analog-to-Digital Converter (ADC) with 16 channels and 11-bit ENOB
- 2x Analog comparator with adjustable reference
4 configurable logic units
Pre-loaded UART bootloader
128-bit unique device identifier (UUID)
Operating temperature range
- EFM8BB5xFxxG (General): -40ºC to +85ºC
- EFM8BB5xFxxI: (Industrial): -40ºC to +125ºC
- EFM8BB52FxxA: (Automotive): -40ºC to +125ºC
Package options
- EFM8BB51: TSSOP-20, QFN-20
- EFM8BB52: QFN-20, QFN-28, QSOP-24
- Pb-free and RoHS compliant