NE57810S Philipss, NE57810S Datasheet - Page 11

• Manufacturer Part Number: NE57810S
• Description: Advanced DDR memory termination power with external reference in
• Manufacturer: Philipss

For high-performance computer systems, sometimes memory banks
Philips Semiconductors
Cascading the NE57810 for complex memory systems
are driven 180 degrees out of phase with one another such that the
apparent access time is halved (even and odd memory addresses).
To do this, it is recommended that two NE57810s are used, one to
terminate each memory bank.
Cascading NE57810 terminators offers two advantages, it improves
the system noise performance by bringing the memory SIMMs
closer to the terminator, and distributes any heat generated by the
2003 Sep 12
Advanced DDR memory termination power
with external reference in
+V
GND
DD
C
IN
Figure 14. Cascading terminator systems for complex memory systems.
V
ExtRefIn
DD
NE57810
Master
V
SS
C
RefOut
IN
V
TT
TO OTHER
NE57810s
V
ExtRefIn
11
DD
C
(LF)
OUT
terminator system. By using the RefOut pin from one NE57810 to
the ExtRefIn pin for the other NE57810(s) used in the system, one
can always guarantee that the V
of the very tight output voltage regulation of the NE57810, the V
outputs should never be wired together. This is because the
terminators would ‘fight’ one another if their output were different by
only a few millivolts. This method can be used in either the normal
operating mode and the externally programmed operating mode.
This method of use can be seen in Figure 14.
V
REF
NE57810
Slave
V
SS
C
(HF)
OUT
RefOut
V
TT
+V
GND
TT1
TT
C
(LF)
OUT
voltages are identical. Because
C
(HF)
OUT
NE57810
SL01680
+V
GND
Product data
TT2
TT