NEC PD703114 User Manual page 513

(4) D/A converter
The D/A converter is used to generate the voltage that matches the analog input.
The output voltage of the D/A converter is controlled by the successive approximation register (SAR).
(5) Successive approximation register (SAR)
The SAR is a 10-bit register that controls the output value of the D/A converter for comparing with the analog
input voltage value. When an A/D conversion ends, the current contents of the SAR (conversion result) are
stored in an A/D conversion result register (ADCR0m, ADCR1n) (m = 0 to 5, n = 0 to 7). When all specified
A/D conversions end, an A/D conversion end interrupt (INTAD0, INTAD1) is also generated.
(6) A/D conversion result registers 0m, 1n (ADCR0m, ADCR1n)
ADCR0m and ADCR1n are 10-bit registers that hold A/D conversion results (m = 0 to 5, n = 0 to 7).
Whenever an A/D conversion ends, the conversion result from the successive approximation register (SAR)
is loaded.
RESET input sets these registers to 0000H.
(7) Controller
The controller selects an analog input, generates sample and hold circuit operation timing, controls
conversion triggers, and specifies the conversion operation time according to the mode set by the ADSCMn0
or ADSCMn1 register.
(8) ANI0m, ANI1n pins (m = 0 to 5, n = 0 to 7)
The ANI0n and ANI1n pins are the analog input pins of each channel (total of 14 channels for two circuits) for
analog converters 0 and 1. They input analog signals to be A/D converted.
Caution Make sure that the voltages input to ANI0m and ANI1n are within the range of the ratings.
In particular, if a voltage (including noise) higher than AV
and AV (even if within the range of absolute maximum ratings) is input, the conversion
SS1
value of that channel is invalid, and the conversion values of other channels may also be
affected.
(9) AV , AV pins
SS0 SS1
The AV and AV
SS0 SS1
converters 0 and 1, always ensure these pins have the same potential as the V
(10) AV , AV pins
DD0 DD1
The AV and AV
DD0 DD1
used as pins that input a reference voltage (equivalent to the AV
Therefore, the signals input to the ANI0m and ANI1n pins are converted into digital signals, based on the
voltage applied between AV
Even if not using A/D converters 0 and 1, always ensure these pins have the same potential as the V
CHAPTER 11 A/D CONVERTER
pins are the ground voltage pins of A/D converters 0 and 1. Even if not using A/D
pins are the analog power supply pins of A/D converters 0 and 1. These pins are also
and AV and between AV
DD0 SS0
User's Manual U15195EJ5V0UD
and AV
DD0 DD1
pin.
SS
and AV pins of the V850E/IA1).
REF0 REF1
and AV (m = 0 to 5, n = 0 to 7).
DD1 SS1
or lower than AV
SS0
pin.
DD
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