PIC18F45J10 Datasheet, PDF (214/358 Pages) Microchip Technology – 28/40/44-Pin High-Performance RISC Microcontrollers with nanoWatt Technology

PIC18F45J10 FAMILY
The analog reference voltage is software selectable to
either the device’s positive and negative supply voltage
(VDD and VSS), or the voltage level on the RA3/AN3/
VREF+ and RA2/AN2/VREF-/CVREF pins.
The A/D converter has a unique feature of being able
to operate while the device is in Sleep mode. To oper-
ate in Sleep, the A/D conversion clock must be derived
from the A/D’s internal RC oscillator.
The output of the sample and hold is the input into the
converter, which generates the result via successive
approximation.
A device Reset forces all registers to their Reset state.
This forces the A/D module to be turned off and any
conversion in progress is aborted.
Each port pin associated with the A/D converter can be
configured as an analog input, or as a digital I/O. The
ADRESH and ADRESL registers contain the result of
the A/D conversion. When the A/D conversion is com-
plete, the result is loaded into the ADRESH:ADRESL
register pair, the GO/DONE bit (ADCON0 register) is
cleared and A/D Interrupt Flag bit, ADIF, is set. The block
diagram of the A/D module is shown in Figure 17-1.
FIGURE 17-1:
A/D BLOCK DIAGRAM
CHS3:CHS0
1100
1011
1010
1001
1000
0111
0110
0101
10-Bit
Converter
A/D
VAIN
(Input Voltage)
0100
0011
0010
Reference
Voltage
VCFG1:VCFG0
VDD⁽²⁾
X0
VREF+
X1
1X
VREF-
0X
VSS⁽²⁾
0001
0000
AN12
AN11
AN10
AN9
AN8
AN7⁽¹⁾
AN6⁽¹⁾
AN5⁽¹⁾
AN4
AN3
AN2
AN1
AN0
Note 1: Channels AN5 through AN7 are not available in 28-pin devices.
2: I/O pins have diode protection to VDD and VSS.
DS39682C-page 212
Preliminary
© 2007 Microchip Technology Inc.