Datasheet

PIC16F872
DS30221B-page 128  2002 Microchip Technology Inc.
FIGURE 14-5: CLKOUT AND I/O TIMING
TABLE 14-2: CLKOUT AND I/O TIMING REQUIREMENTS
Note: Refer to Figure 14-3 for load conditions.
OSC1
CLKOUT
I/O Pin
(input)
I/O Pin
(output)
Q4
Q1
Q2 Q3
10
13
14
17
20, 21
19
18
15
11
12
16
old value
new value
Param
No.
Symbol Characteristic Min Typ† Max Units Conditions
10* TosH2ckL OSC1
↑ to CLKOUT↓ — 75 200 ns (Note 1)
11* TosH2ckH OSC1
↑ to CLKOUT↑ — 75 200 ns (Note 1)
12* TckR CLKOUT rise time — 35 100 ns (Note 1)
13* TckF CLKOUT fall time — 35 100 ns (Note 1)
14* TckL2ioV CLKOUT
↓ to Port out valid ——0.5TCY + 20 ns (Note 1)
15* TioV2ckH Port in valid before CLKOUT
↑ TOSC + 200 ——ns (Note 1)
16* TckH2ioI Port in hold after CLKOUT
↑ 0——ns (Note 1)
17* TosH2ioV OSC1
↑ (Q1 cycle) to
Port out valid
— 100 255 ns
18* TosH2ioI OSC1
↑ (Q2 cycle) to Port
input invalid (I/O in hold time)
Standard (F) 100 ——ns
Extended (LF) 200 ——ns
19* TioV2osH Port input valid to OSC1
↑ (I/O in setup time) 0 ——ns
20* T
IOR Port output rise time Standard (F) — 10 40 ns
Extended (LF) ——145 ns
21* T
IOF Port output fall time Standard (F) — 10 40 ns
Extended (LF) ——145 ns
22††*T
INP INT pin high or low time TCY ——ns
23††*T
RBP RB7:RB4 change INT high or low time TCY ——ns
* These parameters are characterized but not tested.
† Data in "Typ" column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only and are
not tested.
†† These parameters are asynchronous events not related to any internal clock edges.
Note 1: Measurements are taken in RC mode, where CLKOUT output is 4 x T
OSC.