STM32L151C6 STMicroelectronics, STM32L151C6 Datasheet - Page 16

• Manufacturer Part Number: STM32L151C6
• Description: Ultra-low-power ARM Cortex-M3 MCU with 32 Kbytes Flash, 32 MHz CPU, LCD, USB
• Manufacturer: STMicroelectronics

Specifications of STM32L151C6

• Operating Power Supply Range: 1.65 V to 3.6 V (without BOR) or 1.8 V to 3.6 V (with BOR option)
• Temperature Range: –40 to 85 °C
• 4 Modes: Sleep, Low-power run (9 μA at 32 kHz), Low-power sleep (4.4 μA),Stop with RTC (1.45 μA), Stop (570 nA), Standby (300 nA)
• Ultralow Leakage Per I/o: 50 nA
• Fast Wakeup From Stop: 8 μs
• Core: ARM 32-bit Cortex™-M3 CPU
• Dma: 7-channel DMA controller, supporting timers, ADC, SPIs, I2Cs and USARTs

Functional overview
3.3.4
3.4
16/109
Boot modes
At startup, boot pins are used to select one of three boot options:
●
●
●
The boot loader is located in System Memory. It is used to reprogram the Flash memory by
using USART1 or USART2. For further details please refer to AN2606.
Clock management
The clock controller distributes the clocks coming from different oscillators to the core and
the peripherals. It also manages clock gating for low power modes and ensures clock
robustness. It features:
●
●
●
●
●
●
●
●
Boot from Flash memory
Boot from System Memory
Boot from embedded RAM
Clock prescaler: to get the best tradeoff between speed and current consumption, the
clock frequency to the CPU and peripherals can be adjusted by a programmable
prescaler
Safe clock switching: clock sources can be changed safely on the fly in run mode
through a configuration register.
Clock management: to reduce power consumption, the clock controller can stop the
clock to the core, individual peripherals or memory.
Master clock source: three different clock sources can be used to drive the master
clock:
–
–
–
Auxiliary clock source: two ultralow power clock sources that can be used to drive the
LCD controller and the real-time clock:
–
–
RTC and LCD clock sources: the LSI, LSE or HSE sources can be chosen to clock
the RTC and the LCD, whatever the system clock.
USB clock source: the embedded PLL has a dedicated 48 MHz clock output to supply
the USB interface.
Startup clock: after reset, the microcontroller restarts by default with an internal
2.1 MHz clock (MSI). The prescaler ratio and clock source can be changed by the
application program as soon as the code execution starts.
1-24 MHz high-speed external crystal (HSE), that can supply a PLL
16 MHz high-speed internal RC oscillator (HSI), trimmable by software, that can
supply a PLL
Multispeed internal RC oscillator (MSI), trimmable by software, able to generate 7
frequencies (65.5 kHz, 131 kHz, 262 kHz, 524 kHz, 1.05 MHz, 2.1 MHz, 4.2 MHz)
with a consumption proportional to speed, down to 750 nA typical. When a
32.768 kHz clock source is available in the system (LSE), the MSI frequency can
be trimmed by software down to a ±0.5% accuracy.
32.768 kHz low-speed external crystal (LSE)
37 kHz low-speed internal RC (LSI), also used to drive the independent watchdog.
The LSI clock can be measured using the high-speed internal RC oscillator for
greater precision.
Doc ID 17659 Rev 6
STM32L151xx, STM32L152xx