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STM32L151xC STM32L152xC
Functional overview
52
3.9
LCD (liquid crystal display)
The LCD drives up to 8 common terminals and 44 segment terminals to drive up to 320
pixels.
•
Internal step-up converter to guarantee functionality and contrast control irrespective of
V
DD
. This converter can be deactivated, in which case the V
LCD
pin is used to provide
the voltage to the LCD
•
Supports static, 1/2, 1/3, 1/4 and 1/8 duty
•
Supports static, 1/2, 1/3 and 1/4 bias
•
Phase inversion to reduce power consumption and EMI
•
Up to 8 pixels can be programmed to blink
•
Unneeded segments and common pins can be used as general I/O pins
•
LCD RAM can be updated at any time owing to a double-buffer
•
The LCD controller can operate in Stop mode
•
V
LCD
rail decoupling capability
3.10
ADC (analog-to-digital converter)
A 12-bit analog-to-digital converters is embedded into STM32L151xC and STM32L152xC
devices with up to 25 external channels, performing conversions in single-shot or scan
mode. In scan mode, automatic conversion is performed on a selected group of analog
inputs with up to 24 external channels in a group.
The ADC can be served by the DMA controller.
An analog watchdog feature allows very precise monitoring of the converted voltage of one,
some or all scanned channels. An interrupt is generated when the converted voltage is
outside the programmed thresholds.
The events generated by the general-purpose timers (TIMx) can be internally connected to
the ADC start triggers, to allow the application to synchronize A/D conversions and timers.
An injection mode allows high priority conversions to be done by interrupting a scan mode
which runs in as a background task.
The ADC includes a specific low-power mode. The converter is able to operate at maximum
speed even if the CPU is operating at a very low frequency and has an auto-shutdown
function. The ADC’s runtime and analog front-end current consumption are thus minimized
whatever the MCU operating mode.
Table 6. V
LCD
rail decoupling
Bias
Pin
1/2
1/3
1/4
V
LCDRAIL1
1/2 V
LCD
2/3 V
LCD
1/2 V
LCD
PB2
V
LCDRAIL2
N/A
1/3 V
LCD
1/4 V
LCD
PB12
PE11
V
LCDRAIL3
N/A
N/A
3/4 V
LCD
PB0
PE12