Rainbow Electronics DS1602 User Manual
Ds1602 elapsed time counter, Features, Pin assignment
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Note: Some revisions of this device may incorporate deviations from published specifications known as errata. Multiple revisions of any device
FEATURES
§ Two 32-bit counters keep track of real-time
and elapsed time
§ Counters keep track of seconds for over 125
years
§ Battery powered counter counts seconds from
the time battery is attached until V
BAT
is less
than 2.5V
§ V
CC
powered counter counts seconds while
V
CC
is above V
T P
and retains the count in the
absence of V
CC
under battery backup power
§ Clear function resets selected counter to 0
§ Read/write serial port affords low pin count
§ Maximum current drain of less than 1 µA
from V
BAT
pin when serial port is disabled
§ One byte protocol defines read/write, counter
address and software clear function
§ 8-pin DIP or optional 8-pin SOIC
§ Operating temperature range of -40°C to
+85°C
§ Reduced performance operation down to
V
CC
= 2.5V
§ Underwriters Laboratory (UL) recognized
PIN ASSIGNMENT
Package Dimension Information
PIN DESCRIPTION
RST
- Reset
CLK
- Clock
DQ
- Data Input/Output
GND
- Ground
X1, X2
- Crystal Inputs
V
BAT
- + Battery Input
V
CC
- +5V
DESCRIPTION
The DS1602 is a real-time clock/elapsed time counter designed to count seconds when V
CC
power is
applied and continually count seconds under battery backup power with an additional counter regardless
of the condition of V
CC
. The continuous counter can be used to derive time of day, week, month, and year
by using a software algorithm. The V
CC
powered counter will automatically record the amount of time
that V
CC
power is applied. This function is particularly useful in determining the operational time of
equipment in which the DS1602 is used. Alternatively, this counter can also be used under software
control to record real-time eve nts. Communication to and from the DS1602 takes place via a 3-wire serial
port. A 1-byte protocol selects read/ write functions, counter clear functions and oscillator trim. A low
cost 32.768kHz crystal attaches directly to the X1 and X2 pins. If battery powered-only operation is
desired, the V
BAT
pin must be grounded and the V
CC
pin must be connected to the battery.
DS1602
V
CC
V
BAT
X1
X2
RST
DQ
CLK
GND
1
2
3
4
8
7
6
5
DS1602
RST
DQ
CLK
GND
V
CC
V
BAT
X1
X2
1
2
3
4
8
7
6
5
DS1602
Elapsed Time Counter
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