Required
Throughput
Reference Source Mode Configuration
SAR Clock Speed
Other Register Field Set-
tings
125-180 ksps
Any
Always-On + Burst Mode
(ADEN = 1 ADBMEN = 1)
12.25 MHz
(ADSC = 1)
ADC0PWR = 0x40
ADC0TK = 0x3A
ADRPT = 1
0-125 ksps
External
Burst Mode
(ADEN = 0 ADBMEN = 1)
12.25 MHz
(ADSC = 1)
ADC0PWR = 0x44
ADC0TK = 0x3A
ADRPT = 1
50-125 ksps
Internal
Burst Mode
(ADEN = 0 ADBMEN = 1)
12.25 MHz
(ADSC = 1)
ADC0PWR = 0x44
ADC0TK = 0x3A
ADRPT = 1
0-50 ksps
Internal
Burst Mode
(ADEN = 0 ADBMEN = 1)
4.08 MHz
(ADSC = 5)
ADC0PWR = 0xF4
ADC0TK = 0x34
ADRPT = 1
Notes:
1. ADRPT reflects the minimum setting for this bit field. When using the ADC in burst mode, up to 64 samples may be auto-accumu-
lated per conversion trigger by adjusting ADRPT.
For applications where burst mode is used to automatically accumulate multiple results, additional supply current savings can be realiz-
ed. The length of time the ADC is active during each burst contains power-up time at the beginning of the burst as well as the conver-
sion time required for each conversion in the burst. The power-on time is only required at the beginning of each burst. When compared
with single-sample bursts to collect the same number of conversions, multi-sample bursts will consume significantly less power. For
example, performing an eight-cycle burst of 10-bit conversions consumes about 61% of the power required to perform those same eight
samples in single-cycle bursts. For 12-bit conversions, an eight-cycle burst results in about 85% of the equivalent single-cycle bursts.
See the electrical characteristics tables for details on power consumption and the maximum clock frequencies allowed in each mode.
Figure 12.5. Burst Mode Accumulation Power Savings
EFM8UB3 Reference Manual
Analog-to-Digital Converter (ADC0)
silabs.com
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