PIC18F8520-I/PT Microchip Technology Inc., PIC18F8520-I/PT Datasheet - Page 229

• Manufacturer Part Number: PIC18F8520-I/PT
• Description: 80 PIN, 32 KB FLASH, 2048 RAM, 68 I/O
• Manufacturer: Microchip Technology Inc.

Specifications of PIC18F8520-I/PT

• A/d Inputs: 16-Channel, 10-Bit
• Comparators: 2
• Cpu Speed: 10 MIPS
• Eeprom Memory: 1024 Bytes
• Input Output: 68
• Interface: I2C/SPI/UART/USART
• Memory Type: Flash
• Number Of Bits: 8
• Package Type: 80-pin TQFP
• Programmable Memory: 32K Bytes
• Ram Size: 2K Bytes
• Speed: 40 MHz
• Timers: 2-8-bit, 3-16-bit
• Voltage, Range: 2-5.5 V
• Lead Free Status / Rohs Status: RoHS Compliant part

20.7
When a comparator is active and the device is placed
in Sleep mode, the comparator remains active and the
interrupt is functional, if enabled. This interrupt will
wake-up the device from Sleep mode, when enabled.
While the comparator is powered up, higher Sleep
currents than shown in the power-down current
specification will occur. Each operational comparator
will consume additional current, as shown in the com-
parator specifications. To minimize power consumption
while in Sleep mode, turn off the comparators
(CM<2:0> = 111) before entering Sleep. If the device
wakes up from Sleep, the contents of the CMCON
register are not affected.
20.8
A device Reset forces the CMCON register to its Reset
state, causing the comparator module to be in the Com-
parator Reset mode, CM<2:0> = 000. This ensures
that all potential inputs are analog inputs. Device cur-
rent is minimized when analog inputs are present at
Reset time. The comparators will be powered down
during the Reset interval.
FIGURE 20-4:
 2004 Microchip Technology Inc.
Comparator Operation
During Sleep
Effects of a Reset
VA
PIC18F6520/8520/6620/8620/6720/8720
R
S
Legend:
< 10k
COMPARATOR ANALOG INPUT MODEL
A
IN
C
5 pF
C
V
I
R
R
VA
LEAKAGE
PIN
T
PIN
IC
S
= Input Capacitance
= Threshold Voltage
= Leakage Current at the pin due to various junctions
= Interconnect Resistance
= Source Impedance
= Analog Voltage
V
DD
V
V
T
T
= 0.6V
= 0.6V
20.9
A simplified circuit for an analog input is shown in
Figure 20-4. Since the analog pins are connected to a
digital output, they have reverse biased diodes to V
and V
V
range by more than 0.6V in either direction, one of the
diodes is forward biased and a latch-up condition may
occur. A maximum source impedance of 10 k
recommended for the analog sources. Any external
component connected to an analog input pin, such as
a capacitor or a Zener diode, should have very little
leakage current.
SS
and V
SS
. The analog input, therefore, must be between
Analog Input Connection
Considerations
I
±500 nA
V
LEAKAGE
DD
SS
. If the input voltage deviates from this
R
IC
Comparator
Input
DS39609B-page 227
DD
is