PIC16F1513T-I/SS View Datasheet(PDF) - Microchip Technology

Part Name

Description

Manufacturer

PIC16F1513T-I/SS

28-Pin Flash Microcontrollers with XLP Technology

Microchip Technology 

16.1 ADC Configuration

When configuring and using the ADC the following

functions must be considered:

• Port configuration

• Channel selection

• ADC voltage reference selection

• ADC conversion clock source

• Interrupt control

• Result formatting

16.1.1 PORT CONFIGURATION

The ADC can be used to convert both analog and

digital signals. When converting analog signals, the I/O

pin should be configured for analog by setting the

associated TRIS and ANSEL bits. Refer to

Section 12.0 “I/O Ports” for more information.

Note:

Analog voltages on any pin that is defined

as a digital input may cause the input buf-

fer to conduct excess current.

16.1.2 CHANNEL SELECTION

There are up to 21 channel selections available:

- AN<19:8, 4:0> pins

- VREF+ (ADC positive reference)

- VREF- (ADC negative reference)

- Temperature Indicator

- FVR (Fixed Voltage Reference) Output

Refer to Section 14.0 “Fixed Voltage Reference

(FVR)” and Section 15.0 “Temperature Indicator

Module” for more information on these channel

selections.

The CHS bits of the ADCON0 register determine which

channel is connected to the sample and hold circuit.

When changing channels, a delay is required before

starting the next conversion. Refer to Section 16.6

“Hardware CVD Operation” for more information.

16.1.3 ADC VOLTAGE REFERENCE

The ADPREF bits of the ADCON1 register provides

control of the positive voltage reference. The positive

voltage reference can be:

• VREF+ pin

• VDD

• FVR (Fixed Voltage Reference)

See Section 14.0 “Fixed Voltage Reference (FVR)”

for more details on the fixed voltage reference.

PIC16(L)F1512/3

16.1.4 CONVERSION CLOCK

The source of the conversion clock is software

selectable via the ADCS bits of the ADCON1 register.

There are seven possible clock options:

• FOSC/2

• FOSC/4

• FOSC/8

• FOSC/16

• FOSC/32

• FOSC/64

• FRC (dedicated internal oscillator)

The time to complete one bit conversion is defined as

TAD. One full 10-bit conversion requires 11.5 TAD

periods as shown in Figure 16-2.

For correct conversion, the appropriate TAD specifica-

tion must be met. Refer to the A/D conversion require-

ments in Section 25.0 “Electrical Specifications” for

more information. Table 16-1 gives examples of

appropriate ADC clock selections.

Note:

Unless using the FRC, any changes in the

system clock frequency will change the

ADC clock frequency, which may

adversely affect the ADC result.

 2012-2014 Microchip Technology Inc.

DS40001624C-page 125

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