M41T82
M41T83
Serial I2C bus real-time clock with battery switchover
Features
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Ultra-low battery supply current of 365 nA
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Factory calibrated accuracy ±5 ppm
guaranteed after 2 reflows (SOX18)
– Much better accuracies achievable using
built-in programmable analog and digital
calibration circuits
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2.0 V to 5.5 V clock operating voltage
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QFN16, 4 mm x 4 mm
(VFQFPN16)
Counters for tenths/hundredths of seconds,
seconds, minutes, hours, day, date, month,
year, and century
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Automatic switchover and reset output circuitry
(fixed reference)
– M41T83S
VCC = 3.00 V to 5.50 V
(2.85 V ≤ VRST ≤ 3.00 V)
– M41T83R
VCC = 2.70 V to 5.50 V
(2.55 V ≤ VRST ≤ 2.70 V)
– M41T83Z
VCC = 2.38 V to 5.50 V
(2.25 V ≤ VRST ≤ 2.38 V)
18
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SOX18 (18-pin, 300 mil SOIC
with embedded crystal)
SO8
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Serial interface supports I C bus (400 kHz
protocol)
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Programmable alarm with interrupt function
(valid even during battery backup mode)
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RESET (RST) output
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Watchdog timer
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Operating temperature of –40 °C to 85 °C
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Package options include:
– a 16-lead QFN (M41T83),
– an 18-lead embedded crystal SOIC
(M41T83), or
– an 8-lead SOIC (M41T82)
RoHS compliance: lead-free components are
compliant with the RoHS directive
Battery low flag
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7 bytes of battery-backed user SRAM
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Battery or SuperCap™ backup
Programmable 8-bit counter/timer
■
■
Square wave output defaults to 32 KHz on
power-up (M41T83 only)
■
Oscillator stop detection
Optional 2nd programmable alarm available
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2
Low operating current of 80 µA
October 2011
Doc ID 12578 Rev 13
1/63
www.st.com
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