Rainbow Electronics DS1672 User Manual
Ds1672, Low-voltage serial timekeeping chip, General description
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GENERAL DESCRIPTION
The DS1672 low-voltage serial timekeeping chip
incorporates a 32-bit counter and power-
monitoring functions. The 32-bit counter is
designed to count seconds and can be used to
derive time-of-day, week, month, month, and
year by using a software algorithm. A precision,
temperature-compensated reference and
comparator circuit monitors the status of V
CC
.
When an out-of-tolerance condition occurs, an
internal power-fail signal is generated that forces
the reset to the active state. When V
CC
returns to
an in-tolerance condition, the reset signal is kept
in the active state for 250ms to allow the power
supply and processor to stabilize.
FEATURES
§ 32-bit counter
§ 2-wire serial interface
§ Automatic power-fail detect and switch
circuitry
§ Power-fail reset output
§ Low-voltage oscillator operation (1.3V min)
§ Trickle charge capability
§ Underwriters Laboratory (UL) recognized
ORDERING INFORMATION
PART
TEMP
RANGE
PIN-
PACKAGE
TOP
MARK
DS1672-2
-40°C to +85°C
8 0.300" DIP
DS1672-2
DS1672-3
-40°C to +85°C
8 0.300" DIP
DS1672-3
DS1672-33
-40°C to +85°C
8 0.300" DIP
DS1672-33
DS1672S-2
-40°C to +85°C
8 0.150" SO
DS1672-2
DS1672S-3
-40°C to +85°C
8 0.150" SO
DS1672-3
DS1672S-33
-40°C to +85°C
8 0.150" SO
DS1672-33
DS1672U-2
-40°C to +85°C
8 µSOP
1672rr-2
DS1672U-3
-40°C to +85°C
8 µSOP
1672rr-22
DS1672U-
33
-40°C to +85°C
8 µSOP
1672rr-33
PIN CONFIGURATION
Package Dimension Information
DS1672
Low-Voltage Serial Timekeeping Chip
www.maxim-ic.com
www.maxim-ic.com
TYPICAL OPERATING CIRCUIT
1
2
3
4
8
7
6
5
V
CC
RST
SCL
SDA
X1
X2
V
BACKUP
GND
TOP VIEW