IDT1339
REAL-TIME CLOCK WITH SERIAL I
2
C INTERFACE RTC
IDT®
REAL-TIME CLOCK WITH SERIAL I
2
C INTERFACE 16
IDT1339 REV S 031014
AC Electrical Characteristics
Unless stated otherwise, V
CC
= MIN to MAX, Ambient Temperature -40 to +85C, Note 13
WARNING: Under no circumstances are negative undershoots, of any amplitude, allowed when device is in
battery-backup mode.
Note 1: Limits at -40°C are guaranteed by design and are not production tested.
Note 2: SCL only.
Note 3: SDA and SQW/INT
.
Note 4: I
CCA
—SCL at f
SC
max, VIL = 0.0V, VIH = V
CC
, trickle charger disabled.
Note 5: Specified with the I
2
C bus inactive, VIL = 0.0V, VIH = V
CC
, trickle charger disabled.
Note 6:
V
CC
must be less than 3.63 V if the 250 resistor is selected.
Parameter Symbol Conditions Min. Typ. Max. Units
SCL Clock Frequency f
SCL
Fast Mode 100 400 kHz
Standard Mode 100
Bus Free Time Between a STOP and
START Condition
t
BUF
Fast Mode 1.3 µs
Standard Mode 4.7
Hold Time (Repeated) START
Condition, Note 8
t
HD:STA
Fast Mode 0.6 µs
Standard Mode 4.0
Low Period of SCL Clock t
LOW
Fast Mode 1.3 µs
Standard Mode 4.7
High Period of SCL Clock t
HIGH
Fast Mode 0.6 µs
Standard Mode 4.0
Setup Time for a Repeated START
Condition
t
SU:STA
Fast Mode 0.6 µs
Standard Mode 4.7
Data Hold Time, Notes 9, 10 t
HD:DAT
Fast Mode 0 0.9 µs
Standard Mode 0
Data Setup Time, Note 11 t
SU:DAT
Fast Mode 100 ns
Standard Mode 250
Rise Time of Both SDA and SCL
Signals, Note 12
t
R
Fast Mode 20 + 0.1C
B
300 ns
Standard Mode 20 + 0.1C
B
1000
Fall Time of Both SDA and SCL Signals,
Note 12
t
F
Fast Mode 20 + 0.1C
B
300 ns
Standard Mode 20 + 0.1C
B
300
Setup Time for STOP Condition t
SU:STO
Fast Mode 0.6 µs
Standard Mode 4.0
Capacitive Load for Each Bus Line,
Note 12
C
B
400 pF
I/O Capacitance (SDA, SCL) C
I/O
Note 13 10 pF
Oscillator Stop Flag (OSF) Delay t
OSF
Note 14 100 ms
