MPC860DP FREESCALE [Freescale Semiconductor, Inc], MPC860DP Datasheet - Page 12

• Manufacturer Part Number: MPC860DP
• Description: Hardware Specifications
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

Bus Signal Timing
All output pins on the MPC860 have fast rise and fall times. Printed circuit (PC) trace interconnection length should
be minimized in order to minimize undershoot and reflections caused by these fast output switching times. This
recommendation particularly applies to the address and data buses. Maximum PC trace lengths of 6 inches are
recommended. Capacitance calculations should consider all device loads as well as parasitic capacitances due to the
PC traces. Attention to proper PCB layout and bypassing becomes especially critical in systems with higher
capacitive loads because these loads create higher transient currents in the V
inputs or signals that will be inputs during reset. Special care should be taken to minimize the noise levels on the
PLL supply pins.
9 Bus Signal Timing
Table 7
The maximum bus speed supported by the MPC860 is 66 MHz. Higher-speed parts must be operated in half-speed
bus mode (for example, an MPC860 used at 80 MHz must be configured for a 40 MHz bus).
The timing for the MPC860 bus shown assumes a 50-pF load for maximum delays and a 0-pF load for minimum
delays.
12
Num
B5
B1a
B1b
B1c
B1d
B1e
B1g
B1h
B1f
B1
B2
B3
B4
B7
provides the bus operation timing for the MPC860 at 33, 40, 50, and 66 MHz.
33
CLKOUT period
EXTCLK to CLKOUT phase skew
(EXTCLK > 15 MHz and MF <= 2)
EXTCLK to CLKOUT phase skew
(EXTCLK > 10 MHz and MF < 10)
CLKOUT phase jitter (EXTCLK >
15 MHz and MF <= 2)
CLKOUT phase jitter
CLKOUT frequency jitter (MF < 10)
CLKOUT frequency jitter (10 < MF
< 500)
CLKOUT frequency jitter (MF > 500)
1
Frequency jitter on EXTCLK
CLKOUT pulse width low
CLKOUT width high
CLKOUT rise time
CLKOUT fall time
CLKOUT to A(0:31), BADDR(28:30),
RD/WR, BURST, D(0:31), DP(0:3)
invalid
1
Characteristic
3
3
1
1
MPC860 Family Hardware Specifications, Rev. 7
2
Table 7. Bus Operation Timings
1
30.30
–0.90
–2.30
–0.60
–2.00
12.12
12.12
7.58
Min
—
—
—
—
—
—
33 MHz
30.30
Max
0.90
2.30
0.60
2.00
0.50
2.00
3.00
0.50
4.00
4.00
—
—
—
25.00
–0.90
–2.30
–0.60
–2.00
10.00
10.00
6.25
Min
—
—
—
—
—
—
40 MHz
30.30
Max
0.90
2.30
0.60
2.00
0.50
2.00
3.00
0.50
4.00
4.00
—
—
—
CC
20.00
–0.90
–2.30
–0.60
–2.00
8.00
8.00
5.00
Min
and GND circuits. Pull up all unused
—
—
—
—
—
—
50 MHz
30.30
Max
0.90
2.30
0.60
2.00
0.50
2.00
3.00
0.50
4.00
4.00
—
—
—
15.15
–0.90
–2.30
–0.60
–2.00
Freescale Semiconductor
6.06
6.06
3.80
Min
—
—
—
—
—
—
66 MHz
30.30
Max
0.90
2.30
0.60
2.00
0.50
2.00
3.00
0.50
4.00
4.00
—
—
—
Unit
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
%
%
%
%