Direct Rambus™ RIMM™
Module Specification
Version 1.0
®
Direct RambusTM RIMMTM Module Specification 1.0
Copyright 2000 Rambus Inc. All rights reserved.
Rambus, RDRAM, and the Rambus Logo are registered trademarks of Rambus Inc. Direct Rambus, RIMM, SO-
RIMM, and Dir ect RDRAM are trademarks of Rambu s Inc.
Rambus Inc. assumes no responsibility or liab ility for any use of the inf ormation con t ained herein. RAMBUS
SHALL HAVE NO LIABILITY, DIRECT, INDIRECT, OR OTHERWISE, ARISING OUT OF THIS DIRECT
RAMBUS RIMM MODULE SPECIFICATION OR THE USE THEREOF. Direct RDRAMs are manufactured and
sold by Rambus RDRAM licensees. Rambus DRAM licensees provide data sheets specific to their RDRAM
products. For a list of Rambus licensees who are providing Direct RDRAMs, refer to our website: http://
www.rambus.com.
Data contained in this document is preliminary and subject to change without notice. Rambus Inc. assumes no
responsibility for any errors that may appear in th is d ocument. Rambus Inc. ma kes no warranties, express or
implied, of func tionality or suitability for any purpos e. TH IS D I RE CT RAMBUS RIMM MODULE SPECIFI-
CATION IS PROVIDED “AS IS” WITH NO WARRANTIES WHATSOEVER, INCLUDING WITHOUT
LIMITATION ANY WARRANTY OF MERCHANT ABILITY, OR FITNESS FOR ANY PARTICULAR PURPOSE. No
license is granted by implication, estoppel or otherwise under any patent or other intellectual property rights of
Ramb us I nc.
Ramb us I nc.
2465 Latham Street
Mountain View, California USA
94040
Telephone: 650-944-8000
Fax: 650-944-8080
http://www.rambus.com
®
Direct RambusTM RIMM TM Module Specification 1.0 Page i
Table of Contents
Chapter 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
1.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
1.1.1 RIMM Configurations Supported . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Chapter 2 Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1 Environmental . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1.1 Temperature and Humidity Limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1.2 Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.2 Mechanical Design. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.2.1 Dimensions and Tolerances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.2.2 Module Drawing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.2.3 Weight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.2.4 Plating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.2.5 Contact Requirement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.2.6 Keying . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.3 Reliability Requirement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.4 RIMM Module Validation Requirement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.5 Module Pinout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.5.1 Signal Types. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.6 RIMM Module Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.7 RIMM Layout Restrictions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
2.7.1 Routing Restrictions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
2.7.2 Placement Restrictions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
2.8 DC Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
2.8.1 Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
2.9 AC Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
2.9.1 Fixtures & Probes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
2.9.2 Impedance Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
2.9.3 Propagation Delay Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
2.9.4 Delta Propagation Delay Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
2.9.5 Attenuation Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
2.9.6 Crosstalk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
2.9.7 AC Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
2.10 RDRAM Component Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
2.11 SPD Component Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
Page ii Direct RambusTM RIMMTM Module Specification 1.0
Direct RambusTM RIMM TM Module Specification 1.0 Page iii
List of Figures
Figure 2-1: RIMM Module Mechanical Drawing 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Figure 2-2: RIMM Module Mechanical Drawing 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Figure 2-3: Module Keying. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Figure 2-4: RIMM Module Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Figure 2-5: Trace Length Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Figure 2-6: 1.375” RIMM Module Mechanical Drawing with Heatspeader and Component Placement Restrictions
12
Figure 2-7: 1.25” RIMM Module Mechanical Drawing with Heatspeader and Component Placement Restrictions .
13
Figure 2-8: Measure Impedance and Propagation Delay by TDR. . . . . . . . . . . . . . . . . . . . . . . . 15
Figure 2-9: Signal Attenuation Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Figure 2-10:Crosstalk Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Page iv Direct RambusTM RIMMTM Module Specification 1.0
Direct RambusTM RIMM TM Module Specification 1.0 Page v
List of Tables
Table 2-1: RIMM Module Temperature, Humidity and Barometric Pressure Requirements . . . . . . . . . . . 3
Table 2-2: Keying Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Table 2-3: Device Signal Level Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Table 2-4: Module Pinout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Table 2-5: Routing Restrictions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Table 2-6: Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Table 2-7: Design Characterization Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Table 2-8: AC Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Table 2-9: Adjusted DTPD specification:. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Table 2-10: EEPROM Component Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . 21
Table 2-11: EEPROM Component Operating Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Page vi Direct RambusTM RIMMTM Module Specification 1.0
Direct RambusTM RIMM TM Module Specification 1.0 Page 1-1
C
hapter
1Introduction
1.1 Introduction
This specification defines the electrical and mechanical requirements for 184 pin, 2.5 volt,
600 or 800 MHz, 16-bit and 1 8-b it, Direct RDRAM RIMM memory modules. A principal
use of these RIMM modules is for main memory when installed on personal computer
motherboards.
These requirements support interchangeable modules of 1 to 16 RDRAM devices to be
used in Rambus Channel. Direct Rambus Channel supports up to three RIMM modules.
1.1.1 RIMM Configurations Supported
RIMM modules can support 1 to 16 Direct RDRAM devices per module. The basic design
of the RIMM should not preclude the ability to design any capacity RIMM. However,
there are several configuration that should be most popular:
1) Maximum capacity: 16 RDRAM RIMM modules are available fo r maximum capacity
systems.
2) Typical module configurations: 4, 6, 8, and 16 using 64Mb/72Mb RDR AM devices
(32MB, 48MB, 64MB, and 128MB) will most likely be the minimum memory size to be
shipped with any PC as base memory.
Introduction
Page 1-2 Direct RambusTM RIMMTM Module Specification 1.0
Direct RambusTM RIMM TM Module Specification 1.0 Page 2-3
C
hapter
2Specifications
2.1 Environmental
The RIMM module must operate within a personal computer cabinet in an office or home
environment.
2.1.1 Temperature and Humidity Limits
The environmental parameters fo r both storage and operating cond itions are listed in
Table 2-1.
Table 2-1: RIMM Module Temperature, Humidity and Barometric Pressure Requirements
2.1.2 Safety
The RIMM module printed wiring board is to have a flammability rating of 94V-O. Mark-
ings should include UL tractability requirements per UL Recognized Component Directory.
2.2 Mec hanical Desi gn
2.2.1 Dimensions and Tolerances
The module is a multi-layer PC board. PC board thickness is 1.27 ± 0.10mm (0.050 ± 0.004
in) measured at the contact pads. Maximum warpage is 1% (0.01 mm per mm).
The board manufacturer must maintain 28 Ω + 10% impedance for the loaded and
unloaded sections of all RSL signal traces on the module. In addition, the board manufac-
turer should maint ain the impedance of the tw o high speed CMOS signals (SCK and
CMD) to 28 Ω + 10% for the loaded sections and 28 Ω + 15% for the unloaded sections.
Environmental Condition Limit
Ambient Operating Temperature (Ta) Application dependent, 0 °C to +55 °C typically
Operating Humidity 10% to 90% relative humidity
Storage Temperature -50 °C to +100 °C
Storage Humidity 5% to 95% without condensation
Barometric Pressure (operating & storage) 105K - 69K Pascal (up to 3000 meters)
Direct RambusTM RIMM TM Module Specification 1.0 Page 2-5
Figure 2-2: RIMM Module Mechanical Drawing 2
The contact region must be clear of solder mask. PCB designers should avoid placing
additional vias in this region.
2.2.3 Weight
Weight = 45 grams, maximum.
Center of gravity specifications: a maximum of 35 mm from the bottom edge of the RIMM
module.
2.2.4 Plating
Contact pad thicknesses are 0.75 microns (30 micro-inches) gold over a minimum of 2
microns (80 micro-inches) nickel.
2.2.5 Contact Requirement
Leading edge of contact pads specified as the keep out zone must be free of burrs and
external tie bars (see Figure 2-2). The tie bar must be offset from the center line.
2.2.6 Keying
The RIMM module will be keyed for insertion orientation, safety, and configuration. To
allow for future expansions, there are three possible keying options in the RIMM module
designs. The left key which is indicated as DATUM A is fixed, but the center key can be
moved 1.0 mm or 2.0 mm to the right. The default is option A as shown in Figure .
Specifications
Page 2-6 Direct RambusTM RIMMTM Module Specification 1.0
Figure 2-3: Module Keying
The following table describes a few possible options:
Table 2-2: Keying Options
2.3 Reliability Requirement
TBD.
2.4 RIMM Module Validation Requirement
See RIMM Module Validation Specification.
Option Connector Key Module Key Module Description
1AAV
DD=2.5V
2BBTBD
3CCTBD
DATUM A
12.50 mm
Option A (default):
Option B:
DATUM A
11.50 mm
DATUM A
13.50 mm
Option C:
Direct RambusTM RIMM TM Module Specification 1.0 Page 2-7
2.5 Module Pinout
2.5.1 Signal Types
Table 2-3 summarizes the types of signals used in the RIMM module. In the table, RSL
stands for Rambus Signaling Levels.
Table 2-3 : Device Signal Level Summary
For simplicity, the following d efinitions are used:
❏ClockF romM aster (CFM), ClockToMaster (C T M) and their complements, CFMN and
CTMN, are described as Clock.
❏Bi-directional DQA[8:0] and DQB[8:0] data signals ar e collectively referred to as Data.
DQ is a s y nonym for Data.
❏Uni-directional RO W[2:0] and COL[4:0] request signals are simply referred to as
Reque s t. RQ is a synonym for Req u est.
❏CMOS SCK, CMD, and SIN and SOUT control signals are collectively called Serial.
The RIMM module pinout has the prefixes (Lxxx or Rxxx) for all signals to distinguish the
locations of the signals relative to pin A1. Signals with Lxxx pref ix (left side of the module)
is closer to pin A1, and signals with Rxxx prefix (right side of the module) is closer to pin
A92.
a. SCK and CM D are input on ly. SIN and S O U T are inp u t /output.
Pin Type Levels IO Polarity
Clock RSL I Active low
Data RSL IO Active low
Request RSL I Active low
Serial CMOS I, IOaActive high
Power Gnd, VDD, VREF, VCMOS Power DC voltages
Specifications
Page 2-8 Direct RambusTM RIMMTM Module Specification 1.0
Table 2-4: Module Pinout
Pin Pin Name Pin Pin Name Pin Pin Name Pin Pin Name
A1 Gnd B1 Gnd A47 RSRV17-(NC) B47 RSR18V-(NC)
A2 LDQA8 B2 LDQA7 A48 RSRV19-(NC) B48 RSRV20-(NC)
A3 Gnd B3 Gnd A49 RSRV21-(NC) B49 RSRV22-(NC)
A4 LDQA6 B4 LDQA5 A50 RSRV23-(NC) B50 RSRV24-(NC)
A5 Gnd B5 Gnd A51 Vref B51 Vref
A6 LDQA4 B6 LDQA3 A52 Gnd B52 Gnd
A7 Gnd B7 Gnd A53 SCL B53 SA0
A8 LDQA2 B8 LDQA1 A54 Vdd B54 Vdd
A9 Gnd B9 Gnd A55 SDA B55 SA1
A10 LDQA0 B10 LCFM A56 SVdd B56 SVdd
A11 Gnd B11 Gnd A57 SWP B57 SA2
A12 LCTMN B12 LCFMN A58 Vdd B58 Vdd
A13 Gnd B13 Gnd A59 RSCK B59 RCMD
A14 LCTM B14 RSRV1 (NC) A60 Gnd B60 Gnd
A15 Gnd B15 Gnd A61 RDQB7 B61 RDQB8
A16 RSRV2 (NC) B16 LR OW2 A62 Gnd B62 Gnd
A17 Gnd B17 Gnd A63 RDQB5 B63 RDQB6
A18 LROW1 B18 LROW0 A64 Gnd B64 Gnd
A19 Gnd B19 Gnd A65 RDQB3 B65 RDQB4
A20 LCOL4 B20 LCOL3 A66 Gnd B66 Gnd
A21 Gnd B21 Gnd A67 RDQB1 B67 RDQB2
A22 LCOL2 B22 LCOL1 A68 Gnd B68 Gnd
A23 Gnd B23 Gnd A69 RCOL0 B69 RDQB0
A24 LCOL0 B24 LDQB0 A70 Gnd B70 Gnd
A25 Gnd B25 Gnd A71 RCOL2 B71 RCOL1
A26 LDQB1 B26 LDQB2 A72 Gnd B72 Gnd
A27 Gnd B27 Gnd A73 RCOL4 B73 RCOL3
A28 LDQB3 B28 LDQB4 A74 Gnd B74 Gnd
A29 Gnd B29 Gnd A75 RROW1 B75 RROW0
A30 LDQB5 B30 LDQB6 A76 Gnd B76 Gnd
A31 Gnd B31 Gnd A77 RSRV7 (NC) B77 RROW2
A32 LDQB7 B32 LDQB8 A78 Gnd B78 Gnd
A33 Gnd B33 Gnd A79 RCTM B79 RSRV8 (NC)
A34 LSCK B34 LCMD A80 Gnd B80 Gnd
A35 Vcmos B35 Vcmos A81 RCTMN B81 RCFMN
A36 SOUT B36 SIN A82 Gnd B82 Gnd
A37 Vcmos B37 Vcmos A83 RDQA0 B83 RCFM
A38 RSRV3 (NC) B38 RSRV4 (NC) A84 Gnd B84 Gnd
A39 Gnd B39 Gnd A85 RDQA2 B85 RDQA1
A40 RSRV5 (NC) B40 RSRV6 (NC) A86 Gnd B86 Gnd
A41 Vdd B41 Vdd A87 RDQA4 B87 RDQA3
A42 Vdd B42 Vdd A88 Gnd B88 Gnd
A43 RSRV9-(NC) B43 RSRV10-(NC) A89 RDQA6 B89 RDQA5
A44 RSRV11-(NC) B44 RSRV12-(NC) A90 Gnd B90 Gnd
A45 RSRV13-(NC) B45 RSRV14-(NC) A91 RDQA8 B91 RDQA7
A46 RSRV15-(NC) B46 RSRV16-(NC) A92 Gnd B92 Gnd
Direct RambusTM RIMM TM Module Specification 1.0 Page 2-9
2.6 RIMM Module Block Diagram
Figure 2-4: RIMM Module Block Diagram
LDQA[8:0]
LDQB[8:0]
LROW[2:0]
LCTM/N
LCFM/N
LSCK
LCMD
SIN
Vref
D0 D1 D2 D15
RDQA[8:0]
RDQB[8:0]
RROW[2:0]
RCTM/N
RCFM/N
RSCK
RCMD
SOUT
Vcmos
Left Paddle Right Paddle
Vdd
Gnd
Vref
Gnd
Vcmos
Gnd
SCL
SA[2:0]
SDA
SWP
Serial PD
47K (Optional)
Recommended bypass: Recommended bypass:
Recommended bypass:
Two 0.1µF per device
(X7R or Z5U; 0603) One 0.1µF per two devices O n e 0.1µF per two de vices
(X7R or Z5U; 0603)
LCOL[4:0] RCOL[4:0]
SVdd (2.5V-3.3V)
RCTM/N
RDQA[8:0]
RCOL[4:0]
SVdd
Gnd
Recommended bypass:
One 0.1µF
(X7R or Z5U; 0603)
(X7R or Z5U; 0603)
One at the connect or pin
(The number of devices per module
can be from one to sixteen)
S
I
O
0
S
I
O
1
S
I
O
0
S
I
O
1
S
I
O
0
S
I
O
1
S
I
O
0
S
I
O
1
Specifications
Page 2-10 Direct RambusTM RIMMTM Module Specification 1.0
2.7 RIMM Layout Restrictions
2.7.1 Routing Restri ctions
Besides meeting th e total delay specified in Table 2-8, the following length restrictions
must be met.
Figure 2-5: Trace Length Definition
Tab le 2-5: Routing Restrictions
The LLEFT and LRIGHT restrictions do not apply to the Continuity RIMM module,
provi de d t h e si g nals s ho uld ha ve a m a x i mu m le n gth as s pecif ie d by the TPD specification.
Length From To Length (mm)
Lleft Edge of connector fin ger The via of the first
RDRAM device 60 (max for 4 device module)
35 (max for 6 device module)
41 (max for 8 device module)
35 (max for 12 device module)
35 (max for 16 device module)
Lright The via of the last
RDRAM device Edge of connector finger 60 (max for 4 device module)
35 (max for 6 device module)
41 (max for 8 device module)
35 (max for 12 device module)
35 (max for 16 device module)
Lleft
Lright
Pin A1
First Device
Last Device
Direct RambusTM RIMM TM Module Specification 1.0 Page 2-11
2.7.2 Placement Restric tions
If the RIMM module is to be used with a heatspreader, the following (Figure 2-6 and
Figure 2-7) are the dimensions and locations of the mounting holes. In order to fit the
heatspreaders currently recommended by Rambus, the RDRAM devices, SPD, capacitors
and resistor must be placed in the designated areas as shown in Figure 2-6 and Figure 2-7.
Figure 2-6 is for 1.375” tall module, and Figure 2-7 is for 1. 25 ” tall module.
Specifications
Page 2-12 Direct RambusTM RIMMTM Module Specification 1.0
Figure 2-6: 1.375” RIMM Module Mechanical Drawing with Heatspeader and Component
Placement Restrictions
Direct RambusTM RIMM TM Module Specification 1.0 Page 2-13
Figure 2-7: 1.2 5” RIMM Module Mechanical Drawing with Heat speader and Com ponent
Placement Restrictions
Specifications
Page 2-14 Direct RambusTM RIMMTM Module Specification 1.0
2.8 DC Electrical Specifications
2.8.1 Absolute Maximum Ratings
Table 2-6: Absolute Maximum Ratings
2.9 AC Electrical Specifications
Design verification by virtue of detailed characterizations is necessary at the prototype
phase to guarantee, by design, compliance with the RIMM module design requirements.
These tests are required at the beginning of the production cycle. These tests should be
performed as often as needed in the pr oduction cycle to make sure the RIMM module still
meets the specifications. It is important to diff er e ntiate characterization tests from produc-
tion tests. The characterization tests are described in this section and specified in Table 2-8.
Table 2-7: Design Charact eri zatio n Parameters
The following sub-sections describe how to measure some of the electrical parameters of
RIMM modules. All the parameters discussed here ca n be measured in either time domain
or frequency domain as shown in Table 2-7. The time domain measurements can be done
with TDR, signal generator, and scope. The frequency domain measur ements can be done
with a vector network analyzer.
The details on frequency domain measurement will be included in a future re vision of this
document.
Symbol Parameter Min Max Unit
VI,ABS Voltage applied to any RSL or CMOS pin with
respect to Gnd -0.3 VDD + 0.3 V
VDD,ABS
VDDA,ABS
Voltage on Vdd and VddA with respect to Gnd
and Gn dA -0.5 VDD + 1.0 V
SYMBOL DESCRIPTION MEASUREMENT METHOD
Z module impedance TDR, tester, or VNA
tPD (β) RSL propagation delay TDT, tester, or VNA
∆tPD (∆β) variation of prop. delay (clock to any other
RSL), related to timing TDT, tester, or VNA
Vαattenuation (rail-to-rail or fo attenuation) function generator/scope,
TDT, tester, or VNA
VXF
VXB
forward and backward crosstalk function generator/scope,
TDT, tester, or VNA
Direct RambusTM RIMM TM Module Specification 1.0 Page 2-15
2.9.1 Fixtures & Probes
To perform the measurements, probes with both signal and ground contacts are required.
The spacing between the probe tips should match the spacing of the contact pads on the
module. A high impedance probe is also required for time domain measurement.
No special fixture is required.
2.9.2 Impedance Measurement
The module impedance can be measured by TDR. The experimental setup is shown in
Figure 2-8. Notice that the module needs to be properly biased with VDD and VREF. Th e
bias T is required only if the TDR cannot tolerate the DC voltage VREF.
A TDR with adjustable risetime is preferred, and the risetime should be set to the
minimum RS L signal risetime. Altern atively, a low pass filter with adequate bandwidth
can be used to change the risetime. Such filtering can be implemented by a hardware filter
or software post processing.
Figure 2-8: Measure Impedance and Pr opa g atio n Dela y by TDR
2.9.3 Propagation Delay Measurement
The propagation delay is measured by the same setup as in impedance measurement. The
TDR also measures the roundtrip delay of the module. On a TDR with adjustable risetime,
the fastest risetime available should be used.
The delay of the critical signals of the module can be characterized by the Vector Network
Analyzer, TD T (Time Domain Transmission) instrument or by the pulse generator and an
Oscilloscope. A 400MHz signal must be provided with the pulse generator. The data
should be taken from the mid-point of the rising or falling edges.
2.9.4 Delta Propagation Delay Measurement
To measure the variance o f propagatio n d e lay, the same setup for propagation d e lay
measurement is repeated for all RSL lines and the high-speed CMOS signals. The
maximum pro pagation del ay variance is defined as the m aximum dif fer ence between a ny
probe
G
S
+
-
VDD
GND
+
-VREF
RIMM Module
bias T
TDR
Measuremen ts: tPD and ZL
Specifications
Page 2-16 Direct RambusTM RIMMTM Module Specification 1.0
RSL signa ls ( including clock signals) and the average of all clock signals (CFM, CFM N,
CTM, and CTMN).
2.9.5 Attenuation Measurement
The frequency dependent signal attenuation can be measured in time domain with a
signal generator and a scope. A sinusoidal signal at the system clock frequency is applied
to an RSL line, and the signal amplitudes at both ends of the module are measured with a
high impedance probe. Notice that the RSL line should be terminated to its characteristic
impedance.
Figure 2-9: Signal Attenuation Measurement
2.9.6 Crosstalk
To meas ure the crosstalk in time domain, both en ds of the quie t victim line must be termi-
nated with its characteristic impedance, as well as the far end of the active signal line. The
experimental setup is illustrated in Figure . Sig na l amplitudes at both ends of the victim
line are measur ed. In addition, the amplitude, VIN, and rise time, tR, of the input signal ar e
required to compute the backward, Kb, and forward, Kf, crosstalk coefficients.
coax cable
+
-
VDD
GND
+
-VREF
RIMM Module
bias T V1 V2
Vα/VIN = (V1-V2)/V1
SG
attenuation = -20 log10 (V2/V1)
Direct RambusTM RIMM TM Module Specification 1.0 Page 2-17
Figure 2-10: Crosstalk Measurement
2.9.7 AC Characteristics
The following AC parameters are for all module sizes unless it is specified.
The 800MHz numbers below apply for the 800MHz speed grade modules when run at
≤800MHz.
The 800MHz numbers below also apply for the 711MHz speed grade modules when run
at ≤711MHz.
The 600MHz numbers below apply for the 600MHz speed grade modules when run at
≤600MHz.
Table 2-8: AC Characteris tics
Symbol Parameter Min Typ Max Unit
TPD Average RSL clock delay a
Continuity Module (0 Device)
600MHz (2 Device Module)
600MHz (4 Device Module)
600MHz (6 Device Module)
600MHz (8 Device Module)
600MHz (12 De vice Module)
600MHz (16 De vice Module)
800MHz (2 Device Module)
800MHz (4 Device Module)
800MHz (6 Device Module)
800MHz (8 Device Module)
800MHz (12 De vice Module)
800MHz (16 De vice Module)
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
1.015
TBD
1.25
1.40
1.60
1.76
2.10
TBD
1.25
1.40
1.56
1.76
2.06
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
+
-
VDD
GND
+
-VREF
RIMM Module
bias T
Pulse VXB VXF
Kb = VXB/VIN
VIN, tR
Kf = VXF/VIN * tR/L
coaxial cable
Generator
L: total signal length
Victim
Active
Specifications
Page 2-18 Direct RambusTM RIMMTM Module Specification 1.0
∆TPD Propagation delay variation of
RSL signals with respect to
TPD a,b
Continuity Module (0 Device)
600MHz (2 Device Module)
600MHz (4 Device Module)
600MHz (6 Device Module)
600MHz (8 Device Module)
600MHz (12 De vice Module)
600MHz (16 De vice Module)
800MHz (2 Device Module)
800MHz (4 Device Module)
800MHz (6 Device Module)
800MHz (8 Device Module)
800MHz (12 De vice Module)
800MHz (16 De vice Module)
-0.010
TBD
-0.021
-0.021
-0.021
-0.021
-0.024
TBD
-0.021
-0.021
-0.021
-0.021
-0.024
-
-
-
-
-
-
-
-
-
-
0.020
TBD
0.021
0.021
0.021
0.021
0.024
TBD
0.021
0.021
0.021
0.021
0.024
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
∆TPD-CMOS Propagation delay v ariation of
SCK and CMD signals with
respect to an average clock
delay a
-0.100 - 0.100 ns
ZLLoaded channel impedance
(RSL,SCK, CMD signals) 25.2 28 30.8 Ω
ZUL-CMOS Unloaded channel impedance
(SCK, CMD only) 23.8 28 32.2 Ω
Vα/VIN Attenuation limit
Continuity Module (0 Device)
600MHz (2 Device Module)
600MHz (4 Device Module)
600MHz (6 Device Module)
600MHz (8 Device Module)
600MHz (12 De vice Module)
600MHz (16 De vice Module)
800MHz (2 Device Module)
800MHz (4 Device Module)
800MHz (6 Device Module)
800MHz (8 Device Module)
800MHz (12 De vice Module)
800MHz (16 De vice Module)
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
8
TBD
8
9
10
18
21
TBD
12
14
16
20
25
%
%
%
%
%
%
%
%
%
%
%
%
%
Symbol Parameter Min Typ Max Unit
Direct RambusTM RIMM TM Module Specification 1.0 Page 2-19
VXF/VIN Forward cross talk coeffic ie nt
(input signal rise time = 300
ps; 20-80%)
Continuity Module (0 Device)
600MHz (2 Device Module)
600MHz (4 Device Module)
600MHz (6 Device Module)
600MHz (8 Device Module)
600MHz (12 De vice Module)
600MHz (16 De vice Module)
800MHz (2 Device Module)
800MHz (4 Device Module)
800MHz (6 Device Module)
800MHz (8 Device Module)
800MHz (12 De vice Module)
800MHz (16 De vice Module)
2
TBD
2
3
4
6
8
TBD
2
3
4
6
8
%
%
%
%
%
%
%
%
%
%
%
%
%
VXB/VIN Backward cross tal k coe f fi-
cient (input signal rise time =
300 ps; 20-80%)
Continuity Module (0 Device)
600MHz (2 Device Module)
600MHz (4 Device Module)
600MHz (6 Device Module)
600MHz (8 Device Module)
600MHz (12 De vice Module)
600MHz (16 De vice Module)
800MHz (2 Device Module)
800MHz (4 Device Module)
800MHz (6 Device Module)
800MHz (8 Device Module)
800MHz (12 De vice Module)
800MHz (16 De vice Module)
1.25
TBD
1.5
1.8
2
2.3
2.5
TBD
1.5
1.8
2
2.3
2.5
%
%
%
%
%
%
%
%
%
%
%
%
%
Symbol Parameter Min Typ Max Unit
Specifications
Page 2-20 Direct RambusTM RIMMTM Module Specification 1.0
Table 2-9: Adjusted ∆TPD specification:
2.10 RDRAM Component Specifications
To gua rantee functionality and compatibility, all devices on a RIMM module must meet
their respective specifications.
a. TPD or Average clock delay is defined as t h e average delay from finger to finger of all RSL cl ock nets (CTM , CT MN , CF M,
and CFMN ).
b. If the module meets the following specification, it passes. If the module does not meet these specifications, then the specifica-
tions can be adjusted by the next table. Note the equation is not applicable to the continuity module.
a. Where N = Numb e r of devic es
∆Z0 = delta Z0 % = (max Z0 - min Z0) / (min Z0)
(max Z0 a nd m in Z0 are obta ine d from the loaded (high impedance) impedance co upons of all RSL layers on the modu le s)
RDC DC Resistance limit
Continuity Module (0 Device)
600MHz (2 Device Module)
600MHz (4 Device Module)
600MHz (6 Device Module)
600MHz (8 Device Module)
600MHz (12 De vice Module)
600MHz (16 De vice Module)
800MHz (2 Device Module)
800MHz (4 Device Module)
800MHz (6 Device Module)
800MHz (8 Device Module)
800MHz (12 De vice Module)
800MHz (16 De vice Module)
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
0.5
TBD
0.6
0.7
0.8
1.1
1.2
TBD
0.6
0.7
0.8
1.1
1.2
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Ω
Symbol Parameter Adjusted Min/Max Absolute
Min/Max Unit
∆TPD Propagation delay variation of
RSL signals with respect to TPD
600MHz (4,6,8 Device Module)
600MHz (12 Device Module)
600MHz (16 Device Module)
800MHz (4,6,8 Device Module)
800MHz (12 Device Module)
800MHz (16 Device Module)
+/- [17 + (18*N*∆Z0)]a
+/- [20 + (18*N*∆Z0)]
+/- [24 + (18*N*∆Z0)]
+/- [17 + (18*N*∆Z0)]
+/- [20 + (18*N*∆Z0)]
+/- [24 + (18*N*∆Z0)]
+/-0.030
+/-0.040
+/-0.050
+/-0.030
+/-0.040
+/-0.050
ns
ns
ns
ns
ns
ns
Symbol Parameter Min Typ Max Unit
Direct RambusTM RIMM TM Module Specification 1.0 Page 2-21
2.11 SPD Component Specifications
The SPD function is implemented using 2048 bit EEPROM component such as the
National NM24C02L, Catalyst CAT24WC02, SGS Thompson 24C02 or other vendors’
equivalent. It is requir ed that the EEPROM device must meet the functional and electrical
specifications listed below.
These devices must also meet their respective component AC and DC specifications. Any
violation of these specifications constitu tes a violation of the RIMM Module Sp ecification
as well.
Table 2-10: EEPROM Component Absolute Maximum Ratings
Parameter Range
All Input or Output Voltages with
respect to Ground 4.6 V to -0.3 V
Ambient Storage Temperature -50 oC to 100 oC
Table 2-11: EEPROM Component Operating Conditions
Parameter Range
Ambient Operating Temperature 0 oC to 70 oC
Positive Power Supply 2.2 V to 3.6 V
Specifications
Page 2-22 Direct RambusTM RIMMTM Module Specification 1.0
RAMBUS INC.
2465 Latham Street
Mountain View, California USA 94040
Telep hon e: 650 -94 4-8 000
Fax: 650-944-8 080
http://www.rambus.com
SL-0006-100
