600
AMD Geode™ LX Processors Data Book
Electrical Specifications
33234H
The data bus on the DDR SDRAM has a low voltage swing
when actively terminated (terminated topology). The termi-
nated topology supports higher data transfer rates and is
less constrained, but it consumes more power. Many
designs should be able to operate reliably without active
termination (unterminated topology). The design con-
straints are smaller memory subsystems and tight control
on routing. See the application note,
AMD Geode™ LX
Processor and CS5535/CS5536 Companion Device Layout
Recommendations
(publication ID #32739), for more infor-
mation.
When series termination resistors are used, as specified in
the
AMD Geode™ LX Processor and CS5535/CS5536
Companion Device Layout Recommendations
, the actual
power provided by the V
MEMLX
supply is split between the
processor and the series and parallel termination (see Fig-
ure 7-1). Therefore, it is impossible to specify the power
used by the processor’s memory subsystem with one hun-
dred percent accuracy. A conservative estimate, is that
32.5% of the power is consumed by the processor and
67.5% by the termination resistors. See the
AMD Geode™
LX Processor Determining Memory Interface I/O Power
Consumption
document (publication ID #40554) for the
detailed analysis. This number is used for the results in DC
Current tables (Tables 7-3, 7-4, and 7-5).
Figure 7-1. V
MEMLX
Power Split
V
MEMLX
V
MEMDIMM
V
TT
Connector
or
Device
MEM
LX
R
P1
R
P2
R
S
Table 7-3. AMD Geode LX [email protected] Processor DC Currents
LX [email protected] (600 MHz), No EEPROM, V
CORE
= 1.4V, TDP
T
= 5.3W, TDP
U
= 5.1W (Note 1)
Symbol
Parameter
Typ Avg
Max
Unit
Comments
I
CC3ON
- CRT Display
Power State:
On (S0/C0)
85
100
mA
I
CC3ON
- TFT Display
37
45
I
COREON
1420
3140
I
MEMON
- Terminated
150
165
Note 2, Note 3
I
MEMON
- Unterminated
90
100
Note 3
I
MEMDDR2ON
80
95
I
CC3IDLE
- CRT Display
Power State:
Active Idle (S0/C1)
85
mA
I
CC3IDLE
- TFT Display
37
I
COREIDLE
1250
I
MEMIDLE
- Terminated
150
Note 2, Note 3
I
MEMIDLE
- Unterminated
80
Note 3
I
CC3SLP
- CRT Display
Power State:
Sleep (S1)
4
mA
I
CC3SLP
- TFT Display
4
I
CORESLP
600
I
MEMSLP
- Terminated
100
Note 2, Note 3
I
MEMSLP
- Unterminated
35
Note 3
Note 1. The AMD Geode LX [email protected] processor operates at 600 MHz. Model numbers reflect performance as described
here:
http://www.amd.com/connectivitysolutions/geodelxbenchmark
.
T = Terminated and U = Unterminated.
Note 2. Calculations are based on a 32.5/67.5 split between V
MEMLX
used by the AMD Geode LX processor and series
termination resistors. See Section 7.4.3 on page 599 for more details.
Note 3. V
MEM
is 2.6V for the LX [email protected] processor.
Summary of Contents for Geode LX 600
Page 14: ...14 AMD Geode LX Processors Data Book Overview 33234H...
Page 20: ...20 AMD Geode LX Processors Data Book Architecture Overview 33234H...
Page 44: ...44 AMD Geode LX Processors Data Book Signal Definitions 33234H...
Page 88: ...88 AMD Geode LX Processors Data Book GLIU Register Descriptions 33234H...
Page 618: ...618 AMD Geode LX Processors Data Book Electrical Specifications 33234H...