7.5 Adaptive Read Technique
117
SAEN
Read Start
@SAEN
highreliable read
BL
BLB
SP2
SP1
Q1
Q2
RdOk
Time [ns]→
Voltage [mV]→
Voltage
[mV]→
Voltage [V]→
Vol tage [mV]→
Fig. 7.14 Waveforms: reliable Read operation
SAEN
Read Start
@SAEN
RdOk lowunreliable read
BL
SP2
SP1
Q1
Q2
SAEN
RdOk
RdNOk
BLB
Voltage [mV] →
Voltage [mV] →
Voltage [mV] →
Voltage [mV] →
Time [ns]→
Fig. 7.15 Waveforms: unreliable Read operation
7.5.2.3 Architecture-3: Self-Adapting SRAM Using RdOK
In this architecture control logic inside the memory processes the RdOK signal from
all the read columns. As shown in Fig. 7.17, the control logic is designed to use
RdOK signals to decide the end of a correct read operation and to pull down WL as
soon as RdOK signals are generated from all read columns. Waveforms for adaptive