SM8580AM
Real-time Clock IC with 4-bit Interface
and Built-in Temperature Sensor
OVERVIEW
The SM8580AM is a real-time clock IC based on a 32.768kHz crystal oscillator, which features a 4-bit parallel
interface for communication with an external microcontroller. It comprises second-counter to year-counter
clock and calendar circuits that feature automatic leap-year adjustment up to year 2099, alarm and timer interrupt functions, clock counter change detect functions, ±30-second correction function, time error correction
function, and built-in temperature sensor. The 4-bit parallel interface is compatible with general-purpose
SRAM over a high-speed bus.
FEATURES
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PINOUT
High-speed bus 4-bit parallel interface
Date, day, hour, minute, and second-counter presettable alarm interrupt
1/4096 seconds to 255 minutes presettable interval
timer interrupt function
2 software-maskable alarm and timer interrupt
outputs
Clock counter change detect functions
4-digit western calendar display
Automatic leap year correction up to year 2099
±30-second adjust function
−195 to +192ppm time error correction range
Built-in temperature sensor
(analog voltage output)
2.4 to 5.5V interface voltage range
1.6 to 5.5V clock voltage range
0.6µA/3V (typ) current consumption
(Top view)
CE0N
1
24
VDD
FCON
XT
FOUT
XTN
VTEMP
NC
AIRQN
NC
TIRQN
NC
A0
CE1
A1
D0
A2
D1
A3
D2
D3
RDN
VSS
12
13
WRN
ORDERING INFORMATION
7.80 ± 0.30
(Unit: mm)
+ 0.1
5
0.15 − 0.0
10.05 ± 0.20
10.20 ± 0.30
0.36 ± 0.10
0.10
0.12 M
0.20
0.10
0.8
0 to 10
0.50 ± 0.20
1.90
24-pin SSOP
5.40 ± 0.20
SM8580AM
PACKAGE DIMENSIONS
1.80
Package
0.10 ± 0.10
Device
SEIKO NPC CORPORATION —1