1. Feature List

The EFM8UB2 highlighted features are listed below.

• Core:

• Pipelined CIP-51 Core

• Fully compatible with standard 8051 instruction set

• 70% of instructions execute in 1-2 clock cycles

• 48 MHz maximum operating frequency

• Memory:

• Up to 64 KB flash memory, in-system re-programmable

from firmware.

• Up to 4352 bytes RAM (including 256 bytes standard 8051

RAM and 4096 bytes on-chip XRAM)

• Power:

• Internal LDO regulator for CPU core voltage

• Internal 5-to-3.3 V LDO allows direct connection to USB

supply net

• Power-on reset circuit and brownout detectors

• I/O: Up to 40 total multifunction I/O pins:

• Flexible peripheral crossbar for peripheral routing

• 10 mA source, 25 mA sink allows direct drive of LEDs

• Clock Sources:

• Internal 48 MHz precision oscillator ( ±1.5% accuracy

without USB clock recovery, ±0.25% accuracy with USB

clock recovery)

• Internal 80 kHz low-frequency oscillator

• External crystal, RC, C, and CMOS clock options

• Timers/Counters and PWM:

• 5-channel Programmable Counter Array (PCA) supporting

PWM, capture/compare, and frequency output modes with

watchdog timer function

• 6 x 16-bit general-purpose timers

• Communications and Digital Peripherals:

• Universal Serial Bus (USB) Function Controller with eight

flexible endpoint pipes, integrated transceiver, and 1 KB

FIFO RAM

• 2 x UART

• SPI™ Master / Slave

• 2 x SMBus™/I2C™ Master / Slave

• External Memory Interface (EMIF)

• Analog:

• 10-Bit Analog-to-Digital Converter (ADC0)

• 2 x Low-current analog comparators

• On-Chip, Non-Intrusive Debugging

• Full memory and register inspection

• Four hardware breakpoints, single-stepping

• Pre-loaded USB bootloader

• Temperature range -40 to 85 ºC

• Single power supply 2.65 to 3.6 V

• QFP48, QFP32, and QFN32 packages

With on-chip power-on reset, voltage supply monitor, watchdog timer, and clock oscillator, the EFM8UB2 devices are truly standalone

system-on-a-chip solutions. The flash memory is reprogrammable in-circuit, providing non-volatile 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. Each device is specified for 2.65 to 3.6 V operation and is available in 32-pin QFN, 32-pin QFP, or 48-pin QFP pack-

ages. All package options are lead-free and RoHS compliant.

EFM8UB2 Data Sheet

Feature List

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