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23.2.6.5 Using the Multiple Sample and Convert (MSC) Bit
To configure the converter to perform successive conversions automatically and as quickly as possible, a
multiple sample and convert function is available. When MSC = 1, CONSEQx > 0, and the sample timer is
used, the first rising edge of the SHI signal triggers the first conversion. Successive conversions are
triggered automatically as soon as the prior conversion is completed. Additional rising edges on SHI are
ignored until the sequence is completed in the single-sequence mode or until the ENC bit is toggled in
repeat-single-channel or repeated-sequence modes. The function of the ENC bit is unchanged when using
the MSC bit.
23.2.6.6 Stopping Conversions
Stopping ADC12 activity depends on the mode of operation. The recommended ways to stop an active
conversion or conversion sequence are:
• Resetting ENC in single-channel single-conversion mode stops a conversion immediately and the
results are unpredictable. For correct results, poll the busy bit until it is reset before clearing ENC.
• Resetting ENC during repeat-single-channel operation stops the converter at the end of the current
conversion.
• Resetting ENC during a sequence or repeat-sequence mode stops the converter at the end of the
sequence.
• Any conversion mode may be stopped immediately by setting the CONSEQx = 0 and resetting ENC
bit. In this case, conversion data are unreliable.
NOTE: No EOS Bit Set For Sequence
If no EOS bit is set and a sequence mode is selected, resetting the ENC bit does not stop
the sequence. To stop the sequence, first select a single-channel mode and then reset ENC.
23.2.7 Using the Integrated Temperature Sensor
To use the on-chip temperature sensor, select the analog input channel INCHx = 1010. Any other
configuration is done as if an external channel was selected, including reference selection, conversion-
memory selection, etc.
The typical temperature sensor transfer function is shown in Figure 23-10. When using the temperature
sensor, the sample period must be greater than 30 µs. The temperature sensor offset error can be large
and needs to be calibrated for most applications. See the device-specific data sheet for parameters. See
Section 24.2.2.1 for the calibration equations.
Selecting the temperature sensor automatically turns on the on-chip reference generator as a voltage
source for the temperature sensor. However, it does not enable the V
REF+
output or affect the reference
selections for the conversion. The reference choices for converting the temperature sensor are the same
as with any other channel.
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ADC12 SLAU144J–December 2004–Revised July 2013
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