C8051F046-GQ Silicon Laboratories Inc, C8051F046-GQ Datasheet - Page 56

• Manufacturer Part Number: C8051F046-GQ
• Description: IC 8051 MCU 32K FLASH 100TQFP
• Manufacturer: Silicon Laboratories Inc
• Series: C8051F04xr

Specifications of C8051F046-GQ

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 25MHz
• Connectivity: CAN, EBI/EMI, SMBus (2-Wire/I²C), SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, Temp Sensor, WDT
• Number Of I /o: 64
• Program Memory Size: 32KB (32K x 8)
• Program Memory Type: FLASH
• Ram Size: 4.25K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 3.6 V
• Data Converters: A/D 13x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 100-TQFP, 100-VQFP
• Processor Series: C8051F0x
• Core: 8051
• Data Bus Width: 8 bit
• Data Ram Size: 4.25 KB
• Interface Type: CAN, SMBus, SPI, UART
• Maximum Clock Frequency: 25 MHz
• Number Of Programmable I/os: 64
• Number Of Timers: 5
• Operating Supply Voltage: 2.7 V to 3.6 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: PK51, CA51, A51, ULINK2
• Development Tools By Supplier: C8051F040DK
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit, 13 Channel
• On-chip Dac: 12 bit, 2 Channel
• Package: 100TQFP
• Device Core: 8051
• Family Name: C8051F04x
• Maximum Speed: 25 MHz
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Details
• Other names: 336-1211

C8051F040/1/2/3/4/5/6/7
5.3.3. Settling Time Requirements
A minimum tracking time is required before an accurate conversion can be performed. This tracking time is
determined by the ADC0 MUX resistance, the ADC0 sampling capacitance, any external source resis-
tance, and the accuracy required for the conversion. Figure 5.5 shows the equivalent ADC0 input circuits
for both differential and Single-ended modes. Notice that the equivalent time constant for both input circuits
is the same. The required settling time for a given settling accuracy (SA) may be approximated by
Equation 5.2. When measuring the Temperature Sensor output, R
Low-Power tracking mode, three SAR clocks are used for tracking at the start of every conversion. For
most applications, these three SAR clocks will meet the tracking requirements. See Table 5.2 for absolute
minimum settling/tracking time requirements.
Where:
SA is the settling accuracy, given as a fraction of an LSB (for example, 0.25 to settle within 1/4 LSB)
t is the required settling time in seconds
R
n is the ADC resolution in bits (12).
56
TOTAL
AIN0.x
AIN0.y
is the sum of the ADC0 MUX resistance and any external source resistance.
RC
Differential Mode
MUX Select
MUX Select
Input
= R
MUX
R
R
Equation 5.2. ADC0 Settling Time Requirements
* C
MUX
MUX
SAMPLE
= 5k
= 5k
Figure 5.5. ADC0 Equivalent Input Circuits
t
C
C
SAMPLE
SAMPLE
=
ln
= 10pF
= 10pF


------ -
SA
2
n



Rev. 1.5
R
TOTAL
C
AIN0.x
SAMPLE
Single-Ended Mode
RC
TOTAL
MUX Select
Input
= R
reduces to R
MUX
R
* C
MUX
SAMPLE
= 5k
MUX
C
. Note that in
SAMPLE
= 10pF