C8051F352 Silicon Laboratories Inc, C8051F352 Datasheet - Page 45

• Manufacturer Part Number: C8051F352
• Description: IC 8051 MCU 8K FLASH 32LQFP
• Manufacturer: Silicon Laboratories Inc
• Series: C8051F35xr

Specifications of C8051F352

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 50MHz
• Connectivity: SMBus (2-Wire/I²C), SPI, UART/USART
• Peripherals: POR, PWM, Temp Sensor, WDT
• Number Of I /o: 17
• Program Memory Size: 8KB (8K x 8)
• Program Memory Type: FLASH
• Ram Size: 768 x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 3.6 V
• Data Converters: A/D 8x16b; D/A 2x8b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 32-LQFP
• Processor Series: C8051F35x
• Core: 8051
• Data Bus Width: 8 bit
• Data Ram Size: 768 B
• Interface Type: I2C, SPI, UART
• Maximum Clock Frequency: 50 MHz
• Number Of Programmable I/os: 17
• Number Of Timers: 4
• Operating Supply Voltage: 2.7 V to 3.6 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 16 bit
• On-chip Dac: 8 bit
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: No

5.3.4. Error Conditions
Any errors during a conversion or calibration are indicated using bits in the ADC0STA register. The
AD0S3C flag will be set to ‘1’ if there is a SINC3 filter clip during the conversion. Likewise, the AD0FFC
flag will be set to ‘1’ if there is a Fast filter clip during the conversion. A filter clip occurs whenever an inter-
nal filter register overflows during a conversion. The AD0OVR flag will be set to ‘1’ if an ADC overrun con-
dition occurs. An overrun occurs if the end of a conversion is reached while the AD0INT flag is still set to ‘1’
from the previous conversion. If the data registers have not been read, the new data values will be
updated, and the previous conversion will be lost. The general AD0ERR flag indicates that an AD0S3C,
AD0FFC, or AD0OVR error condition has occurred, or that a calibration resulted in a value that was
beyond the limits of the offset or gain register. The data output registers are updated at the end of every
conversion regardless of whether or not an error occurs.
5.4.
An 8-bit offset DAC is included, which can be used for offset correction up to approximately ±1/2 of the
ADC’s input range on any PGA gain setting. The ADC0DAC register (Figure 5.11) controls the offset DAC
voltage. The register is decoded as a signed binary word. The MSB (bit 7) determines the sign of the DAC
magnitude (0 = positive, 1 = negative), and the remaining seven bits (bits 6-0) determine the magnitude.
Each LSB of the offset DAC is equivalent to approximately 0.4% of the ADC’s input span. A write to the
ADC0DAC register initiates a change on the offset DAC output.
5.5.
The burnout current sources can be used to detect an open circuit or short circuit at the ADC inputs. The
burnout current sources are enabled by setting the AD0BCE bit in register ADC0CN to ‘1’ (Figure 5.5). The
positive-channel burnout current source sources approximately 2 µA on AIN+, and the negative-channel
burnout current sinks approximately 2 µA on AIN-. If an open circuit exists between AIN+ and AIN- when
the burnout current sources are enabled, the ADC will read a full scale positive value. If a short-circuit
Input Voltage† (AIN+ - AIN-) 24-bit Output Word (C8051F350/1) 16-bit Output Word (C8051F352/3)
Input Voltage† (AIN+ - AIN-) 24-bit Output Word (C8051F350/1) 16-bit Output Word (C8051F352/3)
VREF - 1 LSB
VREF - 1 LSB
Offset DAC
Burnout Current Sources
-VREF / 2
VREF / 2
VREF / 2
+1 LSB
+1 LSB
-1 LSB
-VREF
Table 5.1. ADC0 Unipolar Output Word Coding (AD0POL = 0)
0
0
Table 5.2. ADC0 Bipolar Output Word Coding (AD0POL = 1)
†Input Voltage is voltage at ADC inputs after amplification by the PGA.
†Input Voltage is voltage at ADC inputs after amplification by the PGA.
0xFFFFFF
0x7FFFFF
0xFFFFFF
0xC00000
0x800000
0x000001
0x000000
0x400000
0x000001
0x000000
0x800000
Rev. 0.4
C8051F350/1/2/3
0xFFFF
0xFFFF
0x7FFF
0xC000
0x8000
0x0001
0x0000
0x4000
0x0001
0x0000
0x8000
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