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Product>>MicroController>>STC 8051 series>>STC8A series

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STC8A series

STC8A series of microcontrollers do not require an external crystal oscillator and external reset circuit. They are 8051 microcontrollers with the properties of strong anti-interference/ultra low price/high speed/low power consumption. Under the same operating frequency, STC8A series of microcontrollers are about 12 times faster (11.2 ~ 13.2 times) than traditional 8051. To execute all 111 instructions in sequence, the STC8A series microcontrollers only need 147 clocks, while the traditional 8051 requires 1944 clocks. STC8A series of microcontrollers are single clock/machine cycle (1T) microcontrollers produced by STC. They are new generation 8051 microcontrollers with wide voltage/high speed / high reliability / low power consumption / strong antistatic / strong anti-interference, and is super encrypted. The instruction codes are fully compatible with traditional 8051.

High precision of ±0.3% @+25°C RC clock is integrated in MCU with -1.38% to +1.42% temperature drift under the temperature range of -40°C to +85°C, and -0.88% to +1.05% temperature drift under temperature range from -20°C to +65°C. The frequency of RC clock can be set from 4MHz to 35MHz when programming a MCU using ISP. Note: The maximum frequency must be controlled below 45MHz when the temperature range is -40°C to + 85°C. Moreover, high reliable reset circuit is integrated in MCU with 4 levels optional reset threshold voltages, which can be selected when user programming using ISP. So, external expensive crystal and the external reset circuit can be eliminated completely.

There are three optional clock sources inside the MCU, internal high precision IRC which can be adjusted appropriately, internal 32KHz low speed IRC, external 4MHz~33MHz oscillator or external clock signal. The clock source can be freely chosen in user codes. After the clock source is selected, it may be 8-bit divided and then be supplied to the CPU and the peripherals, such as timers, UARTs, SPI, and so on.

Two low power modes are provided in MCU, the IDLE mode and the STOP mode. In IDLE mode, MCU stops clocking CPU, CPU stops executing instructions without clock, while all peripherals are still working. At this moment, the power consumption is about 1.0mA at 6MHz working frequency. The STOP mode is the power off or power-down mode. At this 1oment, the main clock stops, CPU and all peripherals stop working, and the power consumption can be reduced to about 0.6uA when VCC is 5.0V, 0.4uA when VCC is 3.3V.

The Power-down mode can be woke-up by one of the following interrupts: INT0(P3.2), INT1(P3.3), INT2(P3.6), INT3(P3.7), INT4(P3.0), T0(P3.4), T1(P3.5), T2(P1.2), T3(P0.4), T4(P0.6), RXD(P3.0/P3.6/P1.6/P4.3), RXD2(P1.0/P4.6), RXD3(P0.0/P5.0), RXD4(P0.2/P5.2), CCP0(P1.7/P2.3/P7.0/P3.3), CCP1(P1.6/P2.4/P7.1/P3.2), CCP2(P1.5/P2.5/P7.2/P3.1), CCP3(P1.4/P2.6/P7.3/P3.0), I2C_SDA(P1.4/P2.4/P3.3), SPI_SS(P1.2/P2.2/P3.5) , all I/O interrupts, Comparator, LVD, Power-down wake-up timer.

Rich digital peripherals and analog peripherals are provided in MCU, including UARTs, timers, PCA, enhanced PWMs and I2C, SPI, 12-bit*15 ultra-high-speed ADC with a speed of up to 800K, that is, 800,000 samples per second, and comparator, which can meet the requirements of users when designing a product.

The enhanced dual data pointers are integrated in the STC8A series of microcontrollers. Using user codes, the function of automatic increasing or decreasing of data pointer and automatic switching of two sets of data pointers can be

 

STC8A Products Line