PIC16F873A/876A devices are available only in 28-pin packages, while PIC16F874A/877A devices are available in 40-pin and 44-pin packages. All devices in the PIC16F87XA family share common architecture with the following differences: • The PIC16F873A and PIC16F874A have one-half of the total on-chip memory of the PIC16F876A and PIC16F877A • The 28-pin devices have three I/O ports, while the 40/44-pin devices have five • The 28-pin devices have fourteen interrupts, while the 40/44-pin devices have fifteen • The 28-pin devices have five A/D input channels, while the 40/44-pin devices have eight • The Parallel Slave Port is implemented only on the 40/44-pin devices

• Datasheet