
ML62Q1000 Series User's Manual
Chapter 23 Successive Approximation Type A/D Converter
FEUL62Q1000
23-19
SA-ADC Reference Voltage Control Register (VREFCON)
23.2.14
VREFCON is a special function register (SFR) used to choose the internal reference voltage operation and control the
operation of the temperature sensor,.
Address:
0xF83A(VREFCON)
Access:
R/W
Access size: 8bit
Initial value:
0x00
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Word
-
Byte
-
VREFCON
Bit
-
-
-
-
-
-
-
-
-
-
VREFP
1
VREFP
0
-
-
-
VREFE
N
R/W
R
R
R
R
R
R
R
R
R
R
R/W
R/W
R
R
R
R/W
Initial
value
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Bit No.
Bit symbol
name
Description
7, 6
-
Reserved bit
5, 4
VREFP1
,
VREFP0
These bits are used to choose the reference voltage for the A/D conversion.
00: Voltage input from the VDD pin (Initial value)
01: Voltage input from the VREF pin
10: Voltage generated by the internal reference voltage circuit (approx.1.55V)
11: Do not use (Voltage input from the VDD pin)
3 to 1
-
Reserved bit
0
VREFEN
This bit is used to enable the operation of internal reference voltage and the temperature
sensor. When using the internal reference voltage (approx. 1.55V) or temperature sensor, set
the VREFEN bit to "1".
0: Disable the operation of internal reference voltage and temperature sensor
(Initial value)
1: Enable the operation of internal reference voltage and temperature sensor
[Note]
Ÿ
It takes 200us(Max.) until the internal reference voltage gets stable after setting VREFEN bit to
"
1
"
. Start
the A/D conversion after waiting the stabilization time.
Ÿ
The internal reference voltage(Approx. 1.55V) can be output to the general port(P23) by setting the
VREFEN bit to
"
1
"
and setting 0x70 to P2MOD3 register. However in that case, it is possible to get
incorrect A/D conversion results as affected by external factors.
Ÿ
When using the external reference voltage input from VREF pin(P23), set VREFP1 bit to
"
0
"
and VREFP0
bit to
"
1
"
and P2MOD3 register to 0x00.
Ÿ
The internal reference voltage controlled by the VREFEN bit is for the A/D converter. See the chapter of
"
Analog Comparator
"
for the reference voltage used in the analog comparator.
Содержание ML62Q1000 Series
Страница 17: ...Chapter 1 Overview...
Страница 112: ...Chapter 2 CPU and Memory Space...
Страница 154: ...Chapter 3 Reset Function...
Страница 166: ...Chapter 4 Power Management...
Страница 196: ...Chapter 5 Interrupts...
Страница 248: ...Chapter 6 Clock generation Circuit...
Страница 274: ...Chapter 7 Low Speed Time Base Counter...
Страница 291: ...Chapter 8 16 Bit Timer...
Страница 320: ...Chapter 9 Functional Timer FTM...
Страница 382: ...Chapter 10 Watchdog Timer...
Страница 402: ...Chapter 11 Serial Communication Unit...
Страница 456: ...Chapter 12 I2 C Bus Unit...
Страница 491: ...Chapter 13 I2 C Master...
Страница 512: ...Chapter 14 DMA Controller...
Страница 531: ...Chapter 15 Buzzer...
Страница 550: ...Chapter 16 Simplified RTC...
Страница 559: ...Chapter 17 GPIO...
Страница 594: ...Chapter 18 External Interrupt Function...
Страница 612: ...Chapter 19 CRC Generator...
Страница 632: ...Chapter 20 Analog Comparator...
Страница 644: ...Chapter 21 D A Converter...
Страница 655: ...Chapter 22 Voltage Level Supervisor...
Страница 676: ...Chapter 23 Successive Approximation Type A D Converter...
Страница 709: ...Chapter 24 Regulator...
Страница 714: ...Chapter 25 Flash Memory...
Страница 743: ...Chapter 26 Code Option...
Страница 750: ...Chapter 27 LCD Driver...
Страница 788: ...Chapter 28 On Chip Debug Function...
Страница 795: ...Chapter 29 Safety Function...
Страница 813: ...Appendix A...
Страница 881: ...Revision History...