PIC16F87_05 Datasheet, PDF (56/228 Pages) Microchip Technology – 18/20/28-Pin Enhanced Flash Microcontrollers with nanoWatt Technology

PIC16F87/88
FIGURE 5-4:
BLOCK DIAGRAM OF RA4/AN4/T0CKI/C2OUT PIN
Data
Bus
WR
PORTA
D
Q
CK Q
Data Latch
WR
TRISA
D
Q
CK Q
TRIS Latch
Comparator Mode = 011, 101, 110
Comparator 2 Output
1
0
Analog
Input Mode
RD TRISA
Q
D
VDD
P
VDD
N
VSS
Schmitt Trigger
Input Buffer
RA4 pin
EN
RD PORTA
TMR0 Clock Input
To A/D Module Channel Input (PIC16F88 only)
FIGURE 5-5:
MCLR Circuit
BLOCK DIAGRAM OF RA5/MCLR/VPP PIN
MCLRE
MCLR Filter
Schmitt Trigger
Buffer
Data Bus
RD Port
RD TRIS ^VSS
Q
D
EN
Schmitt Trigger
Input Buffer
RA5/MCLR/VPP pin
VSS
MCLRE
DS30487C-page 54
 2005 Microchip Technology Inc.