C8051F311 Silicon Laboratories Inc, C8051F311 Datasheet - Page 53

• Manufacturer Part Number: C8051F311
• Description: IC 8051 MCU 16K FLASH 28MLP
• Manufacturer: Silicon Laboratories Inc
• Series: C8051F31xr

Specifications of C8051F311

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 25MHz
• Connectivity: SMBus (2-Wire/I²C), SPI, UART/USART
• Peripherals: POR, PWM, Temp Sensor, WDT
• Number Of I /o: 25
• Program Memory Size: 16KB (16K x 8)
• Program Memory Type: FLASH
• Ram Size: 1.25K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 3.6 V
• Data Converters: A/D 17x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 28-VQFN Exposed Pad, 28-HVQFN, 28-SQFN, 28-DHVQFN
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -

The uncalibrated temperature sensor output is extremely linear and suitable for relative temperature mea-
surements (see Table 5.1 for linearity specifications). For absolute temperature measurements, gain and/
or offset calibration is recommended. Typically a 1-point calibration includes the following steps:
Figure 5.3 shows the typical temperature sensor error assuming a 1-point calibration at 25 °C. Note that
parameters which affect ADC measurement, in particular the voltage reference value, will also
affect temperature measurement.
-1.00
-2.00
-3.00
-4.00
-5.00
5.00
4.00
3.00
2.00
1.00
0.00
-40.00
Step 1. Control/measure the ambient temperature (this temperature must be known).
Step 2. Power the device, and delay for a few seconds to allow for self-heating.
Step 3. Perform an ADC conversion with the temperature sensor selected as the positive input
Step 4. Calculate the offset and/or gain characteristics, and store these values in non-volatile
Figure 5.3. Temperature Sensor Error with 1-Point Calibration
and GND selected as the negative input.
memory for use with subsequent temperature sensor measurements.
-20.00
0.00
Temperature (degrees C)
Rev. 1.7
20.00
C8051F310/1/2/3/4/5/6/7
40.00
60.00
80.00
5.00
1.00
4.00
3.00
2.00
0.00
-1.00
-2.00
-3.00
-4.00
-5.00
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