Datasheet

MAX7325
I
2
C Port Expander with 8 Push-Pull
and 8 Open-Drain I/Os
3
Maxim Integrated
PORT AND INTERRUPT INT TIMING CHARACTERISTICS
(V+ = +1.71V to +5.5V, T
A
= -40°C to +125°C, unless otherwise noted. Typical values are at V+ = +3.3V, T
A
= +25°C.) (Note 1)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Port Output Data Valid t
PPV
C
L
≤ 100pF 4 µs
Port Input Setup Time t
PSU
C
L
≤ 100pF 0 µs
Port Input Hold Time t
PH
C
L
≤ 100pF 4 µs
INT Input Data Valid Time t
IV
C
L
≤ 100pF 4 µs
INT Reset Delay Time from STOP t
IP
C
L
≤ 100pF 4 µs
INT Reset Delay Time from
Acknowledge
t
IR
C
L
≤ 100pF 4 µs
TIMING CHARACTERISTICS
(V+ = +1.71V to +5.5V, T
A
= -40°C to +125°C, unless otherwise noted. Typical values are at V+ = +3.3V, T
A
= +25°C.) (Note 1)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Serial-Clock Frequency f
SCL
400 kHz
Bus Free Time Between a STOP
and a START Condition
t
BUF
1.3 µs
Hold Time (Repeated) START
Condition
t
HD
,
STA
0.6 µs
Repeated START Condition
Setup Time
t
SU
,
STA
0.6 µs
STOP Condition Setup Time t
SU
,
STO
0.6 µs
Data Hold Time t
HD
,
DAT
(Note 2) 0.9 µs
Data Setup Time t
SU
,
DAT
100 ns
SCL Clock Low Period t
LOW
1.3 µs
SCL Clock High Period t
HIGH
0.7 µs
Rise Time of Both SDA and SCL
Signals, Receiving
t
R
(Notes 3, 4)
20 +
0.1C
b
300 ns
Fall Time of Both SDA and SCL
Signals, Receiving
t
F
(Notes 3, 4)
20 +
0.1C
b
300 ns
Fall Time of SDA Transmitting t
F,TX
(Notes 3, 4)
20 +
0.1C
b
250 ns
Pulse Width of Spike Suppressed t
SP
(Note 5) 50 ns
Capacitive Load for Each Bus
Line
C
b
(Note 3) 400 pF
RST Pulse Width t
W
500 ns
RST Rising to START Condition
Setup Time
t
RST
1µs
Note 1: All parameters are tested at T
A
= +25°C. Specifications over temperature are guaranteed by design.
Note 2: A master device must provide a hold time of at least 300ns for the SDA signal (referred to V
IL
of the SCL signal) in order to
bridge the undefined region of SCL’s falling edge.
Note 3: Guaranteed by design.
Note 4: C
b
= total capacitance of one bus line in pF. I
SINK
≤ 6mA. t
R
and t
F
measured between 0.3 x V+ and 0.7 x V+.
Note 5: Input filters on the SDA and SCL inputs suppress noise spikes less than 50ns.