Page 10
v 3.2
Datasheet
7/15/99
PowerPC 750TM SCM RISC Microprocessor
Preliminary Copy
AC Electrical Characteristics
This section provides the AC electrical characteristics for the 750. After fabrication, parts are sorted by maxi-
to the AC specifications for that frequency. These specifications are for 200, 225, 233, 250, 266, 275, and
300 MHz processor core frequencies. The processor core frequency is determined by the bus (SYSCLK) fre-
quency and the settings of the PLL_CFG(0-3) signals. Parts are sold by maximum processor core frequency
Clock AC Specications
Table 7.
Clock AC Timing Specications
See Table 2 for operating conditions.
Num
Characteristic
200 MHz
225/233 MHz
250/266 MHz
275 MHz
300 MHz
Unit
Notes
Min
Max
Min
Max
Min
Max
Min
Max
Min
Max
Processor
frequency
150
200
150
233
150
266
150
275
200
300
MHz
VCO frequency
300
400
300
466
300
533
300
550
400
600
MHz
SYSCLK frequency
25
83.3
25
83.3
25
83.3
25
83.3
25
100
MHz
1
SYSCLK cycle time
12
40
12
40
12
40
12
40
10
40
ns
2,3
SYSCLK rise and
fall time
—
2.0
—
2.0
—
2.0
—
2.0
—
2.0
ns
2,3
4
SYSCLK duty cycle
measured at 1.4 V
40
60
40
60
40
60
40
60
40
60
%
3
SYSCLK jitter
—
±150
—
±150
—
±150
—
±150
—
±150
ps
4,3
Internal PLL relock
time
—
100
—
100
—
100
—
100
—
100
s
5
Note:
1. Note: The SYSCLK frequency and the PLL_CFG[0-3] settings must be chosen such that the resulting SYSCLK (bus) fre-
quency, CPU (core) frequency, and PLL (VCO) frequency do not exceed their respective maximum or minimum operating
tings.
2. Rise and fall times for the SYSCLK input are measured from 0.4 to 2.4V.
3. Timing is guaranteed by design and characterization, and is not tested.
4. The total input jitter (short term and long term combined) must be under
±150ps.
5. Relock timing is guaranteed by design and characterization, and is not tested. PLL-relock time is the maximum amount of
time required for PLL lock after a stable VDD and SYSCLK are reached during the power-on reset sequence. This speci-
cation also applies when the PLL has been disabled and subsequently re-enabled during sleep mode. Also note that
HRESET must be held asserted for a minimum of 255 bus clocks after the PLL-relock time during the power-on reset
sequence.
*
Subject to availability - see your marketing representative.