Chapter 4: Timing Specifications; Table 4-1 Timing Requirements For Hypertransport Reference Clock (100Mhz) Output By The Clock Generator - AMD 780E Technical Reference Manual

4.1 HyperTransport
For HyperTransport bus timing information, please refer to CPU specifications.
4.2 HyperTransport

Table 4-1 Timing Requirements for HyperTransport Reference Clock (100MHz) Output by the Clock Generator

Symbol
V
Change in Crossing point voltage over all edges
CROSS
F Frequency
ppm Long Term Accuracy
S Output falling edge slew rate
FALL
S Output rising edge slew rate
RISE
T Jitter, cycle to cycle
jc max
Accumulated jitter over a 10 s period
T
j-accumulated
V Peak to Peak Differential Voltage
D(PK-PK)
V Differential Voltage
D
V
Change in V
D
DC Duty Cycle
Notes:
More details are available in AMD HyperTransport 3.0 Reference Clock Specification and AMD Family 10h Processor Reference Clock
Parameters, order # 34864.
1 Single-ended measurement at crossing point. Value is maximum-minimum over all time. DC value of common mode is not important
due to blocking cap.
2 Minimum frequency is a consequence of 0.5% down spread spectrum.
3 Measured with spread spectrum turned off.
4 Only simulated at the receive die pad. This parameter is intended to give guidance for simulation. It cannot be tested on a tester but
is guaranteed by design.
5 Differential measurement through the range of ±100mV, differential signal must remain monotonic and within slew rate specification
when crossing through this region.
6 T is the maximum difference of t
jc max
7 Accumulated T over a 10s time period, measured with JIT2 TIE at 50ps interval.
jc
8 V is the overall magnitude of the differential signal.
D(PK-PK)
9 V is the amplitude of the ring-back differential measurement, guaranteed by design that the ring-back will not cross 0V V
D(min)
V is the largest amplitude allowed.
D(max)
10 The difference in magnitude of two adjacent V
signal.
11 Defined as t
HIGH
© 2009 Advanced Micro Devices, Inc.
Proprietary
TM
Bus Timing
TM
Reference Clock Timing Parameters
Parameter
cycle to cycle
DDC
between any two adjacent cycles.
CYCLE
DDC
/t .
CYCLE
Timing Specifications
measurements. V is the stable post overshoot and ring-back part of the
DDC
Chapter 4
Minimum Maximum
- 140
99.9 100
-300 +300
-10 -0.5
0.5 10
- 150
-1 1
400 2400
200 1200
-75 75
45 55
45732 AMD 780E Databook 3.10
Unit Note
mV 1
MHz 2
Ppm 3
V/ns 4, 5
V/ns 4, 5
ps 6
ns 7
mV 8
mV 9
mV 10
% 11
.
D
4-1