GS4576S09/18L
On–Die Termination (ODT)
Mode Register Bit 9 (M9) set to 1 during an MRS command enables ODT. With ODT on, the Ds, Qs, and DM are terminated to
VTT with a resistance, RTT. Command, address, QVLD, and clock signals are not terminated. The diagram below shows the
equivalent circuit of a D receiver with ODT. When a Q begins to drive after a Read command is issued, the ODT function is briefly
switched off. When a Q stops driving at the end of a data transfer, ODT is switched back on. D and DM pins are always terminated.
On–Die Termination DC Parameters
Description
Symbol
Min
Max
Units
V
Notes
1, 2
3
V
0.95 * V
1.05 * V
REF
Termination Voltage
On–Die Termination
TT
REF
R
125
185
TT
Notes:
1. All voltages referenced to V (GND).
SS
2.
V
is expected to be set equal to V
and must track variations in the DC level of V
.
REF
TT
REF
3. The R value is measured at 95°C T .
TT
C
On–Die Termination–Equivalent Circuit
VTT
SW
RTT
Receiver
D
VREF
Rev: 1.03 11/2013
10/63
© 2011, GSI Technology
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.
GSI [ GSI TECHNOLOGY ]
