4. V
IH
, V
IL
, and V
HYS
are a function of the internal supply voltage, which is a function of V
PUP
, R
PUP
,
C
BUS
, and timing used. Use of a lower V
PUP
, higher R
PUP
, higher C
BUS
, and shorter t
RCV
creates
lower V
IH
, V
IL
and V
HYS
values.
5. Once V
IH
is crossed on a rising edge of SI/O, the voltage on SI/O must drop at least by V
HYS
to be
detected as a logic ‘0’.
1.5 AT21CS01/11 AC Characteristics
1.5.1 Reset and Discovery Response Timing
Parameter and Condition
(1)(2)
Symbol Standard
Speed
(3)(4)
High Speed Units
Min. Max. Min. Max.
Reset Low Time, Device in Inactive
State
t
RESET
480 — 48 — µs
Discharge Low Time, Device in Active
Write Cycle (t
WR
)
t
DSCHG
150 — 150 — µs
Reset Recovery Time t
RRT
N/A N/A 8 — µs
Discovery Response Request t
DRR
N/A N/A 1 2 - t
PUP
(5)
µs
Discovery Response Acknowledge
Time
t
DACK
N/A N/A 8 24 µs
Master Strobe Discovery Response
Time
t
MSDR
N/A N/A 2 6 µs
SI/O High Time for Start/Stop
Condition
t
HTSS
N/A N/A 150 — µs
Note:
1. Parameters applicable over operating range in AT21CS01/11 DC and AC Operating Range, unless
otherwise noted.
2. AC measurement conditions for the table above:
– Loading capacitance on SI/O: 100 pF
– R
PUP
(bus line pull-up resistor to V
PUP
): 1 kΩ; V
PUP
: 2.7V
3. Due to the fact that the device will default to High-Speed mode upon Reset, the Reset and
Discovery Response Timing after t
RESET
does not apply for Standard Speed mode. High-Speed
mode timing applies in all cases after t
RESET
.
4. Standard Speed is not available on the AT21CS11.
5. t
PUP
is the time required once the SI/O line is released to be pulled up from V
IL
to V
IH
. This value is
application specific and is a function of the loading capacitance on the SI/O line as well as the R
PUP
chosen. Limits for these values are provided in AT21CS01 DC Characteristics(1) and AT21CS11
DC Characteristics(1).
AT21CS01/AT21CS11
© 2017 Microchip Technology Inc.
Datasheet
DS20005857A-page 8
