Maxim Integrated MAX32600, Руководство пользователя

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MAX32600 User’s Guide Analog Front End 8.3 ADC
Scan Mode
PGA Bypass
adc _ sl p _ cnt =
f
target
f
PCLK
−
( N
scan
−
1 )( pga _ trk _ cnt + adc _ acq _ cnt + 7 )
−
adc _ acq _ cnt
−
24
f
S
= ( N
scan
−
1 )( pga
_
trk
_
cnt + adc
_
acq
_
cnt + 7 ) + adc
_
sl p
_
cnt + adc
_
acq
_
cnt + 24
×
f
PCLK
PGA Enabled
adc _ sl p _ cnt
=
f
target
f
PCLK
−
N
scan
× (
pga _ trk _ cnt
+
pga _ acq _ cnt
+
adc _ acq _ cnt
+
8
) −
32
f
S
= (
N
scan
) × (
pga _ trk _ cnt
+
pga _ acq _ cnt
+
adc _ acq _ cnt
+
8
) +
adc _ sl p _ cnt
+
32
×
f
PCLK
Scan Mode with Burst/Decimation
PGA Bypass
adc
_
sl p
_
cnt =
f
target
f
PCLK
−
( 2
adc _ brst _ cnt
×
N
scan
)
−
1 )( pga
_
trk
_
cnt + adc
_
acq
_
cnt + 7 )
−
adc
_
acq
_
cnt
−
24
f
S
= ( 2
adc
_
brst
_
cnt
×
N
scan
)
−
1 ( pga _ trk _ cnt + adc _ acq _ cnt + 7 ) + adc _ sl p _ cnt + adc _ acq _ cnt + 24
×
f
PCLK
PGA Enabled
adc
_
sl p
_
cnt =
f
target
f
PCLK
−
2
adc _ brst _ cnt
×
N
scan
×
( pga
_
trk
_
cnt + pga
_
acq
_
cnt + adc
_
acq
_
cnt + 8 )
−
32
f
S
=
2
adc
_
brst
_
cnt
×
N
scan
× (
pga _ trk _ cnt
+
pga _ acq _ cnt
+
adc _ acq _ cnt
+
8
) +
adc _ sl p _ cnt
+
32
×
f
PCLK
8.3.4.9 Start the Measurement
To begin taking measurements, two register fields must be set.
When ADC_CTRL0.adc_strt_mode is 0, data collection begins when the the CPU ADC data collection start register, ADC_CTRL0.cpu_adc_strt , is set to 1. This is
an active high start signal that starts the programmed data collection sequence when set to 1. It is self-clearing.
When ADC_CTRL0.adc_strt_mode is 1, the ADC data collection will start when Pulse Train 15 is high. Care must be take in the pulse train programming to ensure
that Pulse Train 15 is low before the ADC collection is complete or the collection process will restart.
8.3.5 Registers (ADC)
8.3.5.1 Module ADC Registers
Rev.1.3 April 2015 Maxim Integrated Page 422