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RM0351
Low-power timer (LPTIM)
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Low-power timer (LPTIM)
34.1 Introduction
The LPTIM is a 16-bit timer that benefits from the ultimate developments in power
consumption reduction. Thanks to its diversity of clock sources, the LPTIM is able to keep
running in all power modes except for Standby mode. Given its capability to run even with
no internal clock source, the LPTIM can be used as a “Pulse Counter” which can be useful
in some applications. Also, the LPTIM capability to wake up the system from low-power
modes, makes it suitable to realize “Timeout functions” with extremely low power
consumption.
The LPTIM introduces a flexible clock scheme that provides the needed functionalities and
performance, while minimizing the power consumption.
34.2 LPTIM
main
features
•
16 bit upcounter
•
3-bit prescaler with 8 possible dividing factor (1,2,4,8,16,32,64,128)
•
Selectable clock
–
Internal clock sources: LSE, LSI, HSI16 or APB clock
–
External clock source over LPTIM input (working with no LP oscillator running,
used by Pulse Counter application)
•
16 bit ARR autoreload register
•
16 bit compare register
•
Continuous/one shot mode
•
Selectable software/hardware input trigger
•
Programmable Digital Glitch filter
•
Configurable output: Pulse, PWM
•
Configurable I/O polarity
•
Encoder mode
34.3 LPTIM
implementation
describes LPTIM implementation on STM32L4xx devices: the full set of features
is implemented in LPTIM1. LPTIM2 supports a smaller set of features, but is otherwise
identical to LPTIM1.
Table 201. STM32L4xx LPTIM features
LPTIM modes/features
(1)
1. X = supported.
LPTIM1
LPTIM2
Encoder mode
X
-