C8051F020-TB Silicon Laboratories Inc, C8051F020-TB Datasheet - Page 45

• Manufacturer Part Number: C8051F020-TB
• Description: BOARD PROTOTYPING W/C8051F020
• Manufacturer: Silicon Laboratories Inc
• Type: MCUr

Specifications of C8051F020-TB

• Contents: Board
• Processor To Be Evaluated: C8051F02x
• Interface Type: USB
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• For Use With/related Products: C8051F020
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

5.2.2. Tracking Modes
The AD0TM bit in register ADC0CN controls the ADC0 track-and-hold mode. In its default state, the ADC0 input is
continuously tracked when a conversion is not in progress. When the AD0TM bit is logic 1, ADC0 operates in low-
power track-and-hold mode. In this mode, each conversion is preceded by a tracking period of 3 SAR clocks (after
the start-of-conversion signal). When the CNVSTR signal is used to initiate conversions in low-power tracking mode,
ADC0 tracks only when CNVSTR is low; conversion begins on the rising edge of CNVSTR (see Figure 5.3). Track-
ing can also be disabled (shutdown) when the entire chip is in low power standby or sleep modes. Low-power track-
and-hold mode is also useful when AMUX or PGA settings are frequently changed, to ensure that settling time
requirements are met (see
Timer 2, Timer 3 Overflow;
(AD0STM[1:0]=00, 01, 11)
Write '1' to AD0BUSY
(AD0STM[1:0]=10
SAR Clocks
SAR Clocks
SAR Clocks
ADC0TM=1
ADC0TM=0
ADC0TM=1
ADC0TM=0
CNVSTR
Figure 5.3. 12-Bit ADC Track and Conversion Example Timing
)
A. ADC Timing for External Trigger Source
B. ADC Timing for Internal Trigger Sources
Section “5.2.3. Settling Time Requirements” on page
Low Power
Low Power
or Convert
or Convert
Track or
Convert
Track Or Convert
1
1
Track
2
2
Track
3
3
4
4
1
5
5
2
6
6
3
7
7
Convert
4
8
8
Rev. 1.4
5
9
9
10 11 12 13 14 15 16 17 18 19
10 11 12 13 14 15 16
6
Convert
7
Convert
Convert
8
9
10 11 12 13 14 15 16
46).
C8051F020/1
Low Power Mode
Track
Low Power Mode
Track
45