em78p5842 ELAN Microelectronics Corp, em78p5842 Datasheet - Page 22

• Manufacturer Part Number: em78p5842
• Description: 8-bit Micro-controller
• Manufacturer: ELAN Microelectronics Corp

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* This specification is subject to change without notice.
IOCC (PORTC I/O control, ADC control)
PAGE0 (PORTC I/O control)
Bit 5 ~ Bit 7(IN0~ IN2) : Input channel selection of AD converter
*Before switch to the AD channel, please set the corresponding pin as AD input.
Bit 1 ~ Bit 2 (IOCC1 ~ IOCC2) : PORTC(1~2) I/O direction control register
-
This is a CMOS multi-channel 10-bit successive approximation A/D converter.
Features
These two bits can choose one of three AD input.
X
0 Î put the relative I/O pin as output
1 Î put the relative I/O pin into high impedance
7
* Please avoid AD converter rate over 50K Hz, it maybe decrease ADC’s resolution.
ADCLK1 ADCLK0
IN2
0
0
0
0
1
1
1
1
74.6kHz maximum conversion speed (Crystal mode) at 5V.
Adjusted full scale input
Internal (VDD) reference voltage
8 analog inputs multiplexed into one A/D converter
Power down mode for power saving
A/D conversion complete interrupt
Interrupt register, A/D control and status register, and A/D data register
0
0
1
1
-
X
6
IN1
0
0
1
1
0
0
1
1
ENPLL
0
1
0
1
PLL
-
X
5
IN0
0
1
0
1
0
1
0
1
fpll
Sampling rate
Programmable
83.3K
41.7K
20.8K
10.4K
CLK2 ~ CLK0
-
divider
X
4
1/Mx
Fig.6 ADC voltage control logic
Input
AD1
AD2
AD3
AD4
AD5
AD6
AD7
AD8
fs
ADCLK1~ADCLK0
-
X
3
Operation voltage
Divider
20
Nx
>=3.5V
>=3.0V
>=2.5V
>=2.5V
R/W-1
IOCC2
fadc
2
10-bit
ADC
R/W-1
IOCC1
P90
P91
P62
P63
P64
P65
P92
P93
Pin
1
ADC output
-
X
0
EM785840/5841/5842
8-bit Micro-controller
2004/11/10 V1.2