DS1342 Maxim, DS1342 Datasheet - Page 15

• Manufacturer Part Number: DS1342
• Description: The DS1341/DS1342 low-current real-time clocks (RTCs) are timekeeping devices that provide an extremely low standby current, which permits longer life from a power supply
• Manufacturer: Maxim

To avoid an unintended I
should not be held low longer than t
I
new START condition when SCL is held low for at least
t
SDA is released and allowed to be pulled high by the
external pullup resistor. For the timeout function to work,
the oscillator must be enabled and running.
To achieve the best results when using the DS1341/
DS1342, decouple the V
and/or 0.1FF capacitor. Use a high-quality, ceramic, sur-
face-mount capacitor if possible. Surface-mount compo-
nents minimize lead inductance, which improves perfor-
mance, and ceramic capacitors tend to have adequate
high-frequency response for decoupling applications.
2
TIMEOUTMAX
C interface is in the reset state and can receive a
reads data with ACK or NACK as applicable, and
generates a STOP condition. See Figure 6 for a read
example using the repeated START condition to
specify the starting memory location.
Reading Multiple Bytes from a Slave: The read
operation can be used to read multiple bytes with a
single transfer. When reading bytes from the slave,
the master simply ACKs the data byte if it desires to
read another byte before terminating the transaction.
After the master reads the last byte it must NACK to
indicate the end of the transfer and then it generates
a STOP condition.
Low-Current I
. When the device detects this condition,
Applications Information
Power-Supply Decoupling
CC
2
power supply with a 0.01FF
C interface timeout, SCL
TIMEOUTMIN
Bus Timeout
2
C RTCs for High-ESR Crystals
. The
The CLKIN/INTA output is open drain and, therefore,
requires an external pullup resistor to realize a logic-high
output level.
SDA is an open-drain output and requires an external
pullup resistor to realize a logic-high level.
Because the DS1341/DS1342 do not use clock cycle
stretching, a master using either an open-drain output
with a pullup resistor or CMOS output driver (push-pull)
could be used for SCL.
SUBSTRATE CONNECTED TO GROUND
For the latest package outline information and land patterns
(footprints), go to www.maxim-ic.com/packages. Note that a
“+”, “#”, or “-” in the package code indicates RoHS status only.
Package drawings may show a different suffix character, but
the drawing pertains to the package regardless of RoHS status.
PACKAGE
8 TDFN-EP
8 FSOP
TYPE
PACKAGE
T833+2
SDA and SCL Pullup Resistors
CODE
U8+1
Package Information
Using Open-Drain Outputs
Chip Information
OUTLINE
21-0036
21-0137
NO.
PATTERN NO.
90-0092
90-0059
LAND
15