ML610Q111/ML610Q112 User’s Manual
Chapter 20 Successive Approximation Type A/D Converter
FEUL610Q111
20-17
20.3.2 Operation of the Successive Approximation A/D Converter
Use the following procedure to operate the SA-ADC:
1. Before starting the SA-ADC, start oscillation of the high-speed clock (HSCLK) and wait until the oscillation stabilizes.
2. Set the SA-ADC mode register 0 (SADMOD0), select the analog input channel to convert.
3. When bit 0 (SARUN) of SA-ADC control register 1 (SADCON1) is set to “1”, the SA-ADC circuit becomes active
and performs A/D conversion from the lower channel number that is selected in the SA-ADC mode register
(SADMOD0).
4. A/D conversion results are stored in the applicable SA-ADC result registers (SADRnL, SADRnH), and when A/D
conversion of the largest channel number that is selected is terminated, an SA-ADC conversion termination interrupt
(SADINT) is generated.
5. Finally, by using bit 0 (SALP) of the SADCON0 register, it is possible to specify whether to terminate A/D conversion
(SARUN bit is “0”) or restart A/D conversion automatically at termination of A/D conversion of the last channel.
Even if a channel is switched during A/D conversion, the channel that was selected at the start of A/D conversion is used
until an A/D conversion termination interrupt occurs.
Figure 20-3 shows the SA-ADC operation timing when channel 0 and channel 1 are selected.
Figure 20-3 SA-ADC Operation Timing
Note
:
- When used as an analog input of SA-ADC, set an applicable port as a high impedance output state.
- SA-ADC has a built-in sample-and-hold capacitor of approximately 20pF. Set output impedance of the signal source
connected to analog input (AINn) to be less than 5kΩ to charge sample-and-hold capacitor within about 7.3μs of the
sampling time. When the output impedance can not be less than 5kΩ, connect a capacitor of 0.1μF between the analog
input pin and V
SS
.
- If don't have the capacitance between the analog input pin and V
SS
, remained electric charge in the 20pF capacitor
discharge to the analog input pin and the voltage of analog input pin may fluctuate for an instant. If the input impedance
of analog input is 5kΩ or lower, the A/D conversion result does not have a negative effect.
OSCLK
SARUN
A/D conversion
of channel 0
A/D conversion
of channel 1
SADINT
Conversion time
12.45
μs @8.192MHz
Conversion time
12.45
μs @8.192MHz
A/D operation
signal
Содержание ML610Q111
Страница 1: ...ML610Q111 ML610Q112 User s Manual Issue Date Nov 16 2016 FEUL610Q111 05 ...
Страница 14: ...Chapter 1 Overview ...
Страница 26: ...Chapter 2 CPU and Memory Space ...
Страница 34: ...Chapter 3 Reset Function ...
Страница 38: ...Chapter 4 MCU Control Function ...
Страница 53: ...Chapter 5 Interrupts INTs ...
Страница 81: ...Chapter 6 Clock Generation Circuit ...
Страница 95: ...Chapter 7 Time Base Counter ...
Страница 103: ...Chapter 8 Timers ...
Страница 145: ...Chapter 9 Watchdog Timer ...
Страница 153: ...Chapter 10 PWM ...
Страница 199: ...Chapter 11 Synchronous Serial Port ...
Страница 212: ...Chapter 12 UART ...
Страница 240: ...Chapter 13 I2 C Bus Interface Master ...
Страница 254: ...Chapter 14 I2 C Bus Interface Slave ...
Страница 269: ...Chapter 15 Port A ...
Страница 279: ...Chapter 16 Port B ...
Страница 291: ...Chapter 17 Port C ...
Страница 303: ...Chapter 18 Port D ...
Страница 312: ...Chapter 19 Port AB Interrupts ...
Страница 317: ...Chapter 20 Successive Approximation Type A D Converter ...
Страница 335: ...Chapter 21 Voltage Level Supervisor ...
Страница 342: ...Chapter 22 Analog Comparator ...
Страница 353: ...Chapter 23 Data Flash Memory ...
Страница 373: ...Chapter 24 On chip Debug ...
Страница 375: ...Appendixes ...
Страница 393: ...Appendix E ...
Страница 398: ...Revision History ...