embedded processors controllers

EFM8BB21F16

Every spec below is cited to the manufacturer datasheet. Pick your exact ordering code, compare the closest alternatives, then ask the assistant what it means for your design.

00 — Overview

What the EFM8BB21F16 family does

The EFM8BB2 family are 8-bit microcontrollers featuring a pipelined CIP-51 core running up to 50 MHz. These devices integrate 16 KB of flash memory, 2304 bytes of RAM, and up to 22 multifunction I/O pins. Key specifications include a 12-bit ADC, five 16-bit timers, two UARTs, and SPI/I2C interfaces. Available in commercial, industrial, and automotive temperature grades, they operate on a single 2.2 to 5.25 V supply. The parts come in QFN28, QFN20, and QSOP24 packages. Engineers typically use them for motor control, medical equipment, consumer electronics, lighting systems, and sensor controllers due to their comprehensive peripheral set and small footprint.

Next step

Start building with EFM8BB21F16 → Every number above is cited straight from the datasheet — ask what they mean for your design, and the assistant answers from the same source documents.

Ordering code: EFM8BB21F16A-C-QFN20EFM8BB21F16G-C-QFN20EFM8BB21F16G-C-QSOP24EFM8BB21F16I-C-QFN20EFM8BB21F16I-C-QSOP24

01 — Key specifications

EFM8BB21F16A-C-QFN20 datasheet parameters

Parameter	Min	Typ	Max	Conditions	Source
supply voltage range	3 V	—	5.25 V	5V Voltage Regulator	SiliconLabs datasheet, p. 25 — Table 4.12. 5V Voltage Regulator
input offset voltage	-10 mV	0 V	10 mV	TA = 25 °C; Comparators	SiliconLabs datasheet, p. 26 — Table 4.13. Comparators
operating temperature	-40 °C	—	85 °C	G-grade devices; Recommended Operating Conditions	SiliconLabs datasheet, p. 16 — Table 4.1. Recommended Operating Conditions
clock frequency	0 Hz	—	50 MHz	(at extclk pin); External Clock Input	SiliconLabs datasheet, p. 22 — Table 4.7. External Clock Input
dropout voltage	—	—	800 mV	Output Current = 100 mA; 5V Voltage Regulator	SiliconLabs datasheet, p. 25 — Table 4.12. 5V Voltage Regulator
cpu speed	—	50 MHz	—		SiliconLabs datasheet, p. 1
program memory size	—	15.6 KB	—	flash	SiliconLabs datasheet, p. 4 — 2. Ordering Information
ram size	—	2.25 KB	—	ram	SiliconLabs datasheet, p. 4 — 2. Ordering Information
io count	—	16	—		SiliconLabs datasheet, p. 4 — 2. Ordering Information
adc resolution	—	12 bit	—		SiliconLabs datasheet, p. 23 — Table 4.8. ADC
core size	—	8 bit	—		SiliconLabs datasheet, p. 1
program erase cycles	20 kcycle	100 kcycle	—	endurance(write/erase cycles); Flash Memory	SiliconLabs datasheet, p. 20 — Table 4.4. Flash Memory

02 — FAQ

EFM8BB21F16A-C-QFN20 frequently asked questions

What is the ADC resolution?

The ADC resolution is 12 bit.

What is the clock frequency at the extclk pin for external clock input?

The clock frequency is 50 MHz at the extclk pin for external clock input.

What is the core size of the EFM8BB21F16A-C-QFN20?

The core size is 8 bit.

What is the maximum CPU speed of the EFM8BB21F16A-C-QFN20?

The maximum CPU speed is 50 MHz.

What is the dropout voltage of the EFM8BB21F16A-C-QFN20 when the output current is 100 mA and the voltage regulator is 5V?

The dropout voltage is 800 mV.

What is the input offset voltage for the comparators at TA = 25 °C?

The input offset voltage is 0 V.

What is the I/O count for the EFM8BB21F16A-C-QFN20?

The I/O count is 16.

What is the operating temperature for G-grade devices under Recommended Operating Conditions?

The operating temperature is 85 °C for G-grade devices under Recommended Operating Conditions.

What is the endurance for write/erase cycles of the Flash Memory?

The program erase cycles endurance for the Flash Memory is 100 kcycle.

What is the program memory size of the EFM8BB21F16A-C-QFN20 in flash?

The program memory size is 15.6 KB.

What is the RAM size of the EFM8BB21F16A-C-QFN20?

The RAM size is 2.25 KB.

What is the supply voltage range for the EFM8BB21F16A-C-QFN20 when the 5V Voltage Regulator is active?

The supply voltage range is 5.25 V.

01 — Key specifications

EFM8BB21F16G-C-QFN20 datasheet parameters

Parameter	Min	Typ	Max	Conditions	Source
quiescent current	—	820 µA	1.2 mA	800 kspm, 10-bit conversions or200 kspm, 12-bit conversionsNormal bias settingsVDD = 3.0 V; Analog Peripheral Supply Currents (-40 °C to +125 °C)	SiliconLabs datasheet, p. 18 — 4.1.2 Power Consumption
output current	—	—	100 mA	5V Voltage Regulator	SiliconLabs datasheet, p. 25 — Table 4.12. 5V Voltage Regulator
supply voltage range	3 V	—	5.25 V	5V Voltage Regulator	SiliconLabs datasheet, p. 25 — Table 4.12. 5V Voltage Regulator
input offset voltage	-10 mV	0 V	10 mV	TA = 25 °C; Comparators	SiliconLabs datasheet, p. 26 — Table 4.13. Comparators
cmrr	—	70 dB	—	common; Comparators	SiliconLabs datasheet, p. 26 — Table 4.13. Comparators
operating temperature	-40 °C	—	85 °C	G-grade devices; Recommended Operating Conditions	SiliconLabs datasheet, p. 16 — Table 4.1. Recommended Operating Conditions
clock frequency	0 Hz	—	50 MHz	(at extclk pin); External Clock Input	SiliconLabs datasheet, p. 22 — Table 4.7. External Clock Input
psrr	—	70 dB	—	ADC	SiliconLabs datasheet, p. 23 — Table 4.8. ADC
dropout voltage	—	—	800 mV	Output Current = 100 mA; 5V Voltage Regulator	SiliconLabs datasheet, p. 25 — Table 4.12. 5V Voltage Regulator
cpu speed	—	50 MHz	—		SiliconLabs datasheet, p. 1
program memory size	—	15.6 KB	—	flash	SiliconLabs datasheet, p. 3 — Table 2.1. Product Selection Guide
ram size	—	2.25 KB	—	ram	SiliconLabs datasheet, p. 3 — Table 2.1. Product Selection Guide
io count	—	16	—		SiliconLabs datasheet, p. 3 — Table 2.1. Product Selection Guide
adc resolution	—	12 bit	—		SiliconLabs datasheet, p. 23 — Table 4.8. ADC
core size	—	8 bit	—		SiliconLabs datasheet, p. 1
program erase cycles	20 kcycle	100 kcycle	—	endurance(write/erase cycles); Flash Memory	SiliconLabs datasheet, p. 20 — Table 4.4. Flash Memory
output voltage low	—	—	600 mV	IOL = 13.5 mA, VDD≥ 3.0 V; (high drive); Port I/O	SiliconLabs datasheet, p. 27 — Table 4.14. Port I/O

01 — Key specifications

EFM8BB21F16G-C-QSOP24 datasheet parameters

Parameter	Min	Typ	Max	Conditions	Source
quiescent current	—	820 µA	1.2 mA	800 kspm, 10-bit conversions or200 kspm, 12-bit conversionsNormal bias settingsVDD = 3.0 V; Analog Peripheral Supply Currents (-40 °C to +125 °C)	SiliconLabs datasheet, p. 18 — 4.1.2 Power Consumption
output current	—	—	100 mA	5V Voltage Regulator	SiliconLabs datasheet, p. 25 — Table 4.12. 5V Voltage Regulator
supply voltage range	3 V	—	5.25 V	5V Voltage Regulator	SiliconLabs datasheet, p. 25 — Table 4.12. 5V Voltage Regulator
input offset voltage	-10 mV	0 V	10 mV	TA = 25 °C; Comparators	SiliconLabs datasheet, p. 26 — Table 4.13. Comparators
cmrr	—	70 dB	—	common; Comparators	SiliconLabs datasheet, p. 26 — Table 4.13. Comparators
operating temperature	-40 °C	—	85 °C	G-grade devices; Recommended Operating Conditions	SiliconLabs datasheet, p. 16 — Table 4.1. Recommended Operating Conditions
clock frequency	0 Hz	—	50 MHz	(at extclk pin); External Clock Input	SiliconLabs datasheet, p. 22 — Table 4.7. External Clock Input
psrr	—	70 dB	—	ADC	SiliconLabs datasheet, p. 23 — Table 4.8. ADC
dropout voltage	—	—	800 mV	Output Current = 100 mA; 5V Voltage Regulator	SiliconLabs datasheet, p. 25 — Table 4.12. 5V Voltage Regulator
cpu speed	—	50 MHz	—		SiliconLabs datasheet, p. 1
program memory size	—	15.6 KB	—	flash	SiliconLabs datasheet, p. 3 — Table 2.1. Product Selection Guide
ram size	—	2.25 KB	—	ram	SiliconLabs datasheet, p. 3 — Table 2.1. Product Selection Guide
io count	—	21	—		SiliconLabs datasheet, p. 3 — Table 2.1. Product Selection Guide
adc resolution	—	12 bit	—		SiliconLabs datasheet, p. 23 — Table 4.8. ADC
core size	—	8 bit	—		SiliconLabs datasheet, p. 1
program erase cycles	20 kcycle	100 kcycle	—	endurance(write/erase cycles); Flash Memory	SiliconLabs datasheet, p. 20 — Table 4.4. Flash Memory
output voltage low	—	—	600 mV	IOL = 13.5 mA, VDD≥ 3.0 V; (high drive); Port I/O	SiliconLabs datasheet, p. 27 — Table 4.14. Port I/O

01 — Key specifications

EFM8BB21F16I-C-QFN20 datasheet parameters

Parameter	Min	Typ	Max	Conditions	Source
quiescent current	—	820 µA	1.2 mA	800 kspm, 10-bit conversions or200 kspm, 12-bit conversionsNormal bias settingsVDD = 3.0 V; Analog Peripheral Supply Currents (-40 °C to +125 °C)	SiliconLabs datasheet, p. 18 — 4.1.2 Power Consumption
output current	—	—	100 mA	5V Voltage Regulator	SiliconLabs datasheet, p. 25 — Table 4.12. 5V Voltage Regulator
supply voltage range	3 V	—	5.25 V	5V Voltage Regulator	SiliconLabs datasheet, p. 25 — Table 4.12. 5V Voltage Regulator
input offset voltage	-10 mV	0 V	10 mV	TA = 25 °C; Comparators	SiliconLabs datasheet, p. 26 — Table 4.13. Comparators
cmrr	—	70 dB	—	common; Comparators	SiliconLabs datasheet, p. 26 — Table 4.13. Comparators
operating temperature	-40 °C	—	85 °C	G-grade devices; Recommended Operating Conditions	SiliconLabs datasheet, p. 16 — Table 4.1. Recommended Operating Conditions
clock frequency	0 Hz	—	50 MHz	(at extclk pin); External Clock Input	SiliconLabs datasheet, p. 22 — Table 4.7. External Clock Input
psrr	—	70 dB	—	ADC	SiliconLabs datasheet, p. 23 — Table 4.8. ADC
dropout voltage	—	—	800 mV	Output Current = 100 mA; 5V Voltage Regulator	SiliconLabs datasheet, p. 25 — Table 4.12. 5V Voltage Regulator
cpu speed	—	50 MHz	—		SiliconLabs datasheet, p. 1
program memory size	—	15.6 KB	—	flash	SiliconLabs datasheet, p. 4 — 2. Ordering Information
ram size	—	2.25 KB	—	ram	SiliconLabs datasheet, p. 4 — 2. Ordering Information
io count	—	16	—		SiliconLabs datasheet, p. 4 — 2. Ordering Information
adc resolution	—	12 bit	—		SiliconLabs datasheet, p. 23 — Table 4.8. ADC
core size	—	8 bit	—		SiliconLabs datasheet, p. 1
program erase cycles	20 kcycle	100 kcycle	—	endurance(write/erase cycles); Flash Memory	SiliconLabs datasheet, p. 20 — Table 4.4. Flash Memory
output voltage low	—	—	600 mV	IOL = 13.5 mA, VDD≥ 3.0 V; (high drive); Port I/O	SiliconLabs datasheet, p. 27 — Table 4.14. Port I/O

01 — Key specifications

EFM8BB21F16I-C-QSOP24 datasheet parameters

Parameter	Min	Typ	Max	Conditions	Source
quiescent current	—	820 µA	1.2 mA	800 kspm, 10-bit conversions or200 kspm, 12-bit conversionsNormal bias settingsVDD = 3.0 V; Analog Peripheral Supply Currents (-40 °C to +125 °C)	SiliconLabs datasheet, p. 18 — 4.1.2 Power Consumption
output current	—	—	100 mA	5V Voltage Regulator	SiliconLabs datasheet, p. 25 — Table 4.12. 5V Voltage Regulator
supply voltage range	3 V	—	5.25 V	5V Voltage Regulator	SiliconLabs datasheet, p. 25 — Table 4.12. 5V Voltage Regulator
input offset voltage	-10 mV	0 V	10 mV	TA = 25 °C; Comparators	SiliconLabs datasheet, p. 26 — Table 4.13. Comparators
cmrr	—	70 dB	—	common; Comparators	SiliconLabs datasheet, p. 26 — Table 4.13. Comparators
operating temperature	-40 °C	—	85 °C	G-grade devices; Recommended Operating Conditions	SiliconLabs datasheet, p. 16 — Table 4.1. Recommended Operating Conditions
clock frequency	0 Hz	—	50 MHz	(at extclk pin); External Clock Input	SiliconLabs datasheet, p. 22 — Table 4.7. External Clock Input
psrr	—	70 dB	—	ADC	SiliconLabs datasheet, p. 23 — Table 4.8. ADC
dropout voltage	—	—	800 mV	Output Current = 100 mA; 5V Voltage Regulator	SiliconLabs datasheet, p. 25 — Table 4.12. 5V Voltage Regulator
cpu speed	—	50 MHz	—		SiliconLabs datasheet, p. 1
program memory size	—	15.6 KB	—	flash	SiliconLabs datasheet, p. 4 — 2. Ordering Information
ram size	—	2.25 KB	—	ram	SiliconLabs datasheet, p. 4 — 2. Ordering Information
io count	—	21	—		SiliconLabs datasheet, p. 4 — 2. Ordering Information
adc resolution	—	12 bit	—		SiliconLabs datasheet, p. 23 — Table 4.8. ADC
core size	—	8 bit	—		SiliconLabs datasheet, p. 1
program erase cycles	20 kcycle	100 kcycle	—	endurance(write/erase cycles); Flash Memory	SiliconLabs datasheet, p. 20 — Table 4.4. Flash Memory
output voltage low	—	—	600 mV	IOL = 13.5 mA, VDD≥ 3.0 V; (high drive); Port I/O	SiliconLabs datasheet, p. 27 — Table 4.14. Port I/O

03 — Alternatives

Closest matches to EFM8BB21F16

EFM8BB21F16G similar adc resolution, similar clock frequency, similar cmrr

EFM8BB2F16G similar quiescent current, similar program memory size, similar adc resolution

EFM8BB51F16G-C 7.1× lower output current, 2.0× higher clock frequency, 1.8× lower ram size

EFM8BB51F16G-C-QFN20 7.1× lower output current, 2.0× higher clock frequency, 1.8× lower ram size

EFM8BB10F2A-A-QFN20 9.0× lower ram size, 8.0× lower program memory size, 3.1× lower quiescent current

MSP430FR2310 8.0× lower program memory size, 3.1× lower cpu speed, 2.0× higher core size

PIC16LF1824 9.0× lower ram size, 2.0× lower program memory size, 1.9× higher operating temperature

CH32V003F4U6 4.0× higher core size, 1.9× higher clock frequency, 1.4× higher supply voltage range

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