DS17285/DS17287
ORDERING INFORMATION
PART #
DESCRIPTION
DS17285XX-X RTC Chip
3
5
+3V operating range
+5V operating range
blank commercial temp range
N
industrial temp range
blank 24-pin DIP
E
28- pin TSOP
S
24- pin SO
DS17287X-X RTC Module; 24-pin DIP
3
5
+3V operating rang
+5V operating range
blank commercial temp range
N
industrial
PIN DESCRIPTION
X1
X2
-
-
RCLR
-
AD0–AD7 -
PWR
-
KS
-
CS
-
ALE
-
WR
-
RD
-
IRQ
-
SQW
-
VCC
-
GND
-
VBAT
-
VBAUX -
NC
-
Crystal Input
Crystal Output
RAM Clear Input
Multiplexed Address/Data Bus
Power-On Interrupt Output (Open Drain)
Kickstart Input
RTC Chip-Select Input
RTC Address Strobe
RTC Write Data Strobe
RTC Read Data Strobe
Interrupt Request Output (Open Drain)
Square-Wave Output
+3V or +5V Main Supply
Ground
Battery + Supply
Auxiliary Battery Supply
No Connect
DESCRIPTION
The DS17285/DS17287 are real-time clocks (RTCs) designed as successors to the industry standard
DS1285, DS1385, DS1485, DS1585, and DS1685 PC real-time clocks. These devices provide the
industry standard DS1285 clock function with either +3V or +5V operation. The DS17285 also
incorporates a number of enhanced features including a silicon serial number, power-on/off control
circuitry, 114 bytes of user NV SRAM plus 2kB of additional NV RAM, and 32.768kHz output for
sustaining power management activities.
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