PIC16LC717/P View Datasheet(PDF) - Microchip Technology

Part Name

Description

Manufacturer

PIC16LC717/P

18/20-Pin, 8-Bit CMOS Microcontrollers with 10/12-Bit A/D

Microchip Technology 

PIC16C717/770/771

11.10 A/D Operation During Sleep

The A/D module can operate during SLEEP mode. This

requires that the A/D clock source be configured for RC

(ADCS<1:0> = 11b). With the RC clock source

selected, when the GO/DONE bit is set the A/D module

waits one instruction cycle before starting the conver-

sion cycle. This allows the SLEEP instruction to be exe-

cuted, which eliminates all digital switching noise

during the sample and conversion. When the conver-

sion cycle is completed the GO/DONE bit is cleared,

and the result loaded into the ADRESH and ADRESL

registers. If the A/D interrupt is enabled, the device will

wake-up from SLEEP. If the A/D interrupt is not

enabled, the A/D module will then be turned off,

although the ADON bit will remain set.

When the A/D clock source is another clock option (not

RC), a SLEEP instruction causes the present conver-

sion to be aborted and the A/D module is turned off,

though the ADON bit will remain set.

TABLE 11-2: SUMMARY OF A/D REGISTERS

Turning off the A/D places the A/D module in its lowest

current consumption state.

Note:

For the A/D module to operate in SLEEP,

the A/D clock source must be configured to

RC (ADCS<1:0> = 11b).

11.11 Connection Considerations

Since the analog inputs employ ESD protection, they

have diodes to VDD and VSS. This requires that the

analog input must be between VDD and VSS. If the input

voltage exceeds this range by greater than 0.3V (either

direction), one of the diodes becomes forward biased

and it may damage the device if the input current spec-

ification is exceeded.

An external RC filter is sometimes added for anti-alias-

ing of the input signal. The R component should be

selected to ensure that the total source impedance is

kept under the 2.5 kΩ recommended specification. Any

external components connected (via hi-impedance) to

an analog input pin (capacitor, zener diode, etc.) should

have very little leakage current at the pin.

Address Name

Bit 7 Bit 6 Bit 5

Bit 4 Bit 3 Bit 2

Bit 1

Bit 0

Value on:

POR,

BOR

Value on

all other

Resets

0Bh,8Bh, INTCON

GIE

PEIE

T0IE

10Bh,18Bh

INTE RBIE

T0IF

INTF

RBIF 0000 000x

0Ch

PIR1

—

ADIF

—

—

SSPIF CCP1IF TMR2IF TMR1IF -0-- 0000

8Ch

PIE1

—

ADIE

—

—

SSPIE CCP1IE TMR2IE TMR1IE -0-- 0000

1Eh

ADRESH A/D High Byte Result Register

xxxx xxxx

9Eh

ADRESL A/D Low Byte Result Register

xxxx xxxx

9Bh

REFCON VRHEN VRLEN VRHOEN VRLOEN —

—

—

—

0000 ----

1Fh

ADCON0 ADCS1 ADCS0 CHS2

CHS1 CHS0 GO/DONE CHS3 ADON 0000 0000

9Fh

ADCON1 ADFM VCFG2 VCFG1 VCFG0

—

—

—

—

0000 ----

05h

PORTA PORTA Data Latch when written: PORTA pins when read

000x 0000

06h

PORTB PORTB Data Latch when written: PORTB pins when read

xxxx xx00

85h

TRISA PORTA Data Direction Register

1111 1111

86h

TRISB PORTB Data Direction Register

1111 1111

9Dh

ANSEL

ANS5

ANS4 ANS3 ANS2

ANS1 ANS0 1111 1111

Legend: x = unknown, u = unchanged, - = unimplemented read as ’0’. Shaded cells are not used for A/D conversion.

0000 000u

-0-- 0000

-0-- 0000

uuuu uuuu

uuuu uuuu

0000 ----

0000 0000

0000 ----

000u 0000

uuuu uu00

1111 1111

1111 1111

1111 1111

DS41120A-page 124

Advanced Information

© 1999 Microchip Technology Inc.

Share Link: