DS1688_05 Datasheet, PDF (3/6 Pages) Dallas Semiconductor – 3V/5V Serialized Real-Time Clocks with NV RAM Control

DS1688/DS1691
PIN DESCRIPTION
PIN
SO EDIP
NAME
1
1
V_BAUX
2, 3
—
4
4
X1, X2
RCLR
5–12
13
5–12
13
AD0–AD7
PWR
14, 19
14
15
15
16
16
GND
KS
CS
17
17
ALE
18
18
WR
20
20
RD
21
21
22
22
PSEL
IRQ
23
—
V_BAT
24
24
SQW
25
25
26
26
27
27
28
28
—
2, 3, 19,
23
V_CCO
V_CCI
CEO
CEI
N.C.
FUNCTION
Auxiliary Battery Supply
Crystal Input, Crystal Output
Active-Low RAM Clear Input
Muxed Address/Data Bus
Active-Low Power-On Interrupt Output
Ground
Active-Low Kickstart Input
Active-Low Chip Select Input
Address Strobe
Active-Low Write Data Strobe
Active-Low Read Data Strobe
+3V or +5V Power Select
Active-Low Interrupt Request Output
Battery + Supply
Square-Wave Output. This signal functions identical to the
DS1689/DS1693 with an exception occurring at power-up. A
32kHz square wave is output on this pin, t_REC, after a power-up
condition has been detected. This condition sets the following
bits, enabling the 32kHz output: DV1 = 1, SQWE = 1, and E32K
= 1. The square wave is output on this pin if either SQWE = 1 or
E32K = 1.
RAM Power-Supply Output
+3V or +5V Main Supply
Active-Low RAM Chip Enable Out
Active-Low RAM Chip Enable In
No Connection
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