PIC18F85K22-I/PT Microchip Technology, PIC18F85K22-I/PT Datasheet - Page 361

• Manufacturer Part Number: PIC18F85K22-I/PT
• Description: IC, 8BIT MCU, PIC18F, 64MHZ, TQFP-80
• Manufacturer: Microchip Technology
• Series: PIC® XLP™ 18Fr

Specifications of PIC18F85K22-I/PT

• Controller Family/series: PIC18
• No. Of I/o's: 69
• Eeprom Memory Size: 1KB
• Ram Memory Size: 2KB
• Cpu Speed: 64MHz
• No. Of Timers: 8
• Core Size: 8 Bit
• Program Memory Size: 32KB
• Core Processor: PIC
• Speed: 64MHz
• Connectivity: EBI/EMI, I²C, LIN, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, LVD, POR, PWM, WDT
• Number Of I /o: 69
• Program Memory Type: FLASH
• Eeprom Size: 1K x 8
• Ram Size: 2K x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 5.5 V
• Data Converters: A/D 24x12b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 80-TQFP
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

After the A/D module has been configured as desired,
the selected channel must be acquired before the
conversion can start. The analog input channels must
have their corresponding TRIS bits selected as inputs.
To determine acquisition time, see
Acquisition Requirements”
time has elapsed, the A/D conversion can be started.
An acquisition time can be programmed to occur
between setting the GO/DONE bit and the actual start
of the conversion.
To do an A/D conversion, follow these steps:
1.
FIGURE 23-5:
 2009-2011 Microchip Technology Inc.
Configure the A/D module:
• Configure the required ADC pins as analog
• Set the voltage reference (ADCON1)
• Select the A/D positive and negative input
• Select the A/D acquisition time (ADCON2)
• Select the A/D conversion clock (ADCON2)
• Turn on the A/D module (ADCON0)
pins (ANCON0, ANCON1 and ANCON2)
channels (ADCON0 and ADCON1)
Legend: C
V
AIN
R
S
V
I
R
SS
C
R
LEAKAGE
T
PIN
IC
HOLD
SS
ANALOG INPUT MODEL
ANx
C
5 pF
PIN
. After this acquisition
= Input Capacitance
= Threshold Voltage
= Leakage Current at the pin due to
= Interconnect Resistance
= Sampling Switch
= Sample/Hold Capacitance (from DAC)
= Sampling Switch Resistance
various junctions
Section 23.3 “A/D
V
DD
V
V
T
T
= 0.6V
= 0.6V
PIC18F87K22 FAMILY
I
±100 nA
LEAKAGE
2.
3.
4.
5.
6.
7.
R
IC
Configure the A/D interrupt (if desired):
• Clear the ADIF bit (PIR1<6>)
• Set the ADIE bit (PIE1<6>)
• Set the GIE bit (INTCON<7>)
Wait the required acquisition time (if required).
Start the conversion:
• Set the GO/DONE bit (ADCON0<1>)
Wait for A/D conversion to complete, by either:
• Polling for the GO/DONE bit to be cleared
OR
• Waiting for the A/D interrupt
Read A/D Result registers (ADRESH:ADRESL)
and, if required, clear bit, ADIF.
For the next conversion, begin with Step 1 or 2,
as required.
The A/D conversion time per bit is defined as T
Before the next acquisition starts, a minimum Wait
of 2 T
 1k
AD
is required.
SS
Sampling
Switch
V
DD
R
SS
Sampling Switch
1
V
SS
C
2
HOLD
3
DS39960D-page 361
= 25 pF
(k)
4
AD
.