STM32F103B — Datasheet Summary, Specs & Alternatives

01 — Overview

This ST Microelectronics datasheet covers the STM32F103x8 and STM32F103xB medium-density 32-bit microcontrollers. The document details these Arm Cortex-M3 based devices, which feature 64 or 128 KB of Flash memory and 20 KB of SRAM. Key performance parameters include a maximum clock speed of 72 MHz, an application supply voltage range of 2.0 to 3.6 V, and up to 80 fast I/O ports. Connectivity options span nine interfaces including USB 2.0 full-speed, CAN 2.0B Active, SPI at 18 Mbit/s, and up to three USARTs. Additional features comprise seven timers, two 12-bit ADC converters, low-power modes, and debug capabilities via SWD or JTAG. Available in various packages like LQFP, BGA, and UFQFPN.

02 — Key specifications

Datasheet parameters

Parameter	Min	Typ	Max	Conditions
quiescent current	—	80 µA	100 µA
output current	—	—	25 mA
supply voltage range	2 V	—	3.6 V
operating temperature	-40 °C	—	85 °C	Maximum power dissipation
clock frequency	0 Hz	—	72 MHz
power dissipation	—	—	454 mW	LFBGA100
input capacitance	—	5 pF	—
cpu speed	—	72 MHz	—
program memory size	—	131 kB	—
ram size	—	20.5 kB	—
io count	—	37	—
adc resolution	—	12 bit	—
core size	—	32 bit	—
rise time	4 ns	—	20 ns	CL = 50 pF
fall time	4 ns	—	20 ns	CL = 50 pF
data retention	30 year	—	—	1 kcycle(2)at TA = 85 °C
program erase cycles	10 kcycle	—	—	TA = -40 to +85 °C (6 suffix versions)TA = -40 to +105 °C (7 suffix versions)
sample rate	50 kHz	—	1 MHz

03 — Alternatives

Closest matches to STM32F103B

STM32F103C8T6 3.4× lower quiescent current, 2.0× lower program memory size, similar adc resolution

STM32F411CCU6 6.4× higher ram size, 2.4× lower clock frequency, 2.3× higher cpu speed

STM32F405OET6 9.6× higher ram size, 4.0× higher program memory size, 2.4× lower clock frequency

STM32F030C4K6 10.0× lower program erase cycles, 8.0× lower program memory size, 5.0× lower ram size

STM32G071C8 8.3× higher rise time, 2.4× lower fall time, 2.0× lower program memory size

GD32F103RFT6 10.0× higher program erase cycles, 5.9× higher program memory size, 5.8× lower clock frequency

STM32G070CBT6 10.0× lower program erase cycles, 8.3× higher rise time, 2.4× lower fall time

CH32V203C6T6 4.5× lower clock frequency, 4.0× lower program memory size, 2.2× higher quiescent current

04 — FAQ

Frequently asked questions

What is the ADC resolution of the STM32F103B?

The ADC resolution is 12 bit.

What is the maximum clock frequency of the STM32F103B?

The maximum clock frequency is 72 MHz.

What is the core size of the STM32F103B?

The core size is 32 bit.

What is the maximum CPU speed of the STM32F103B?

The maximum CPU speed is 72 MHz.

What is the data retention period for the STM32F103B after 1 kcycle at TA = 85 °C?

The data retention is 30 year.

What is the fall time when CL = 50 pF?

The fall time is 20 ns when CL = 50 pF.

What is the input capacitance of the STM32F103B?

The input capacitance is 5 pF.

What is the number of I/O ports?

The STM32F103B has 37 I/O ports.