STM8L-DISCOVERY STMicroelectronics, STM8L-DISCOVERY Datasheet - Page 15

• Manufacturer Part Number: STM8L-DISCOVERY
• Description: BOARD EVALUATION STM8L15X
• Manufacturer: STMicroelectronics
• Series: STM8L EnergyLiter
• Type: MCUr

Specifications of STM8L-DISCOVERY

• New! Us2012 Catalog Page: STM8L-Discovery_STM32L152-EVAL
• Contents: Board
• Processor To Be Evaluated: STM8L15X
• Processor Series: STM8
• Data Bus Width: 8 bit
• Interface Type: USART, I2C, SPI
• Core: ARM
• Dimensions: 7 mm x 7 mm
• Operating Supply Voltage: 3.3 V to 5 V
• Silicon Manufacturer: ST Micro
• Core Architecture: STM8
• Core Sub-architecture: STM8
• Silicon Core Number: STM8
• Silicon Family Name: STM8L1xx
• For Use With/related Products: STM8L15x
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-10660

UM0970
3.6.3
Figure 11. STM8L-DISCOVERY I
Low power mode I
The principle used to measure a current when the STM8L152C6T6 is in Low power mode is:
1.
2.
3.
4.
5.
6.
The measurement timing is given in
connected when T1 goes off after entering Low power mode. Q13 output of the counter
allows connection of the 2 KΩ resistor when the current I
Figure 11
edge, the shunt resistor R21 is connected between VDD_MCU and the power supply in
order to reduce the measurement range to 30 uA full scale. Then after another 150 ms for
current stabilization, R21 is shorted, the IDD measurement is stored in C11, and the MCU is
woken up. After wakeup the MCU can measure the IDD current corresponding to the Low
power mode stored in C11.
The Low power mode measurement procedure can be used in Halt or Active halt mode if the
I
should be used up to 30 mA.
DD
current does not exceed 30 uA, otherwise the I
Configure ADC to measure voltage on the IDD_Measurement pin.
Configure PE6 to serve as wakeup pin.
Enter Low power mode after setting IDD_CNT_EN (PC4) signal low.
IDD_WAKEUP rising edge wakes up the MCU after around 300 ms.
Start ADC conversion as soon as possible after wakeup in order to measure the
voltage corresponding to Low power mode on capacitor C11.
Reset the counter by programming IDD_CNT_EN high (in less than 70 ms after the
wakeup) to avoid the R21 2 KΩ resistor being connected later in Run mode.
shows how the counter and T1 ensure that, 150 ms after IDD_CNT_EN falling
DD
DD
Low power mode measurement timing diagram
measurement principle
Doc ID 17693 Rev 1
Figure
11. In Low power modes, the 2 KΩ resistor is
DD
measurement procedure in Run mode
DD
becomes very low.
Hardware and layout
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