SM8578BV Real-time Clock IC
OVERVIEW
The SM8578BV is a serial interface, real-time clock IC that uses a 32.768 kHz crys...
SM8578BV Real-time Clock IC
OVERVIEW
The SM8578BV is a serial interface, real-time clock IC that uses a 32.768 kHz crystal oscillator for its reference timing. It comprises second-counter to year-counter clock and calendar circuits that feature automatic leap-year adjustment, alarm and timer interrupt functions, as well as oscillator stop, timer reloading, and other detection functions. Data is transferred to and from an external controller using a 3-wire serial interface. It is available in compact 8-pin VSOP packages, making it ideal for use in all types of portable, hand-held equipment.
FEATURES
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PINOUT
(Top view)
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1.6 to 5.5V wide operating
voltage range 0.5µA (typ.) current consumption (VDD = 3.0V, CE = Low) 3-wire serial interface control Day, day-of-week, hour, and minute alarm interrupt function 1/4096 seconds to 255 minutes presettable interval timer interrupt function Time update detection function Abnormal oscillation detection function Automatic leap-year adjustment function (Western and Japanese calendars) Oscillator capacitor CD built-in Molybdenum-gate
CMOS process Miniature 8-pin VSOP package
INTN XTN XT VSS
1
8
VDD DATA CLK
4
5
CE
ORDERING INFORMATION,
Device SM8578BV Package 8-pin VSOP
PACKAGE DIMENSIONS
(Unit: mm)
0 to 10°
4.4 ± 0.2
6.4 ± 0.3
0.585typ 1.15 ± 0.05 3.12 ± 0.3
+ 0.1 0.05 0.15 −
0.22 ± 0.1
NIPPON PRECISION CIRCUITS INC.—1
0.05 ± 0.05
0.65
1.30MAX
0.5 ± 0.2
SM8578BV
BLOCK DIAGRAM
VDD VSS
Control ...