R
EM MICROELECTRONIC - MARIN SA
V3020
Ultra Low Power 1-Bit 32 kHz RTC
Description
Features
The V3020 is a low power CMOS real time clock. Data is
transmitted serially as 4 address bits and 8 data bits, over
one line of a standard parallel data bus. The device is
Supply current typically 390 nA at 3V
50 ns access time with 50 pF load capacitance
Fully operational from 1.2V to 5.5V
accessed by chip select ( CS ) with read and write control
timing provided by either RD and WR pulse (Intel CPU)
No busy states or danger of a clock update while
accessing
or DS with advanced R/
W (Motorola CPU). Data can
Serial communication on one line of a standard
parallel data bus or over a conventional 3 wire serial
interface
also be transmitted over a conventional 3 wire serial
interface having CLK, data I/O and strobe. The V3020
has no busy states and there is no danger of a clock
Interface compatible with both Intel and Motorola
update while accessing.
Supply current is typically
Seconds, minutes, hours, day of month, month, year,
week day and week number in BCD format
390 nA at VDD = 3.0V. Battery operation is supported by
complete functionality down to 1.2V. The oscillator is
typically 0.3 ppm/V.
Leap year and week number correction
Time set lock mode to prevent unauthorized setting of
the current time or date
Applications
Oscillator stability 0.3 ppm / volt
No external capacitor needed
Utility meters
Battery operated and portable equipment
Consumer electronics
White/brown goods
Pay phones
Frequency measurement and test modes
Temperature range: -40°C to +85°C
On request extended temperature range, -40°C to
+125°C
Cash registers
Pin compatible with the V3021
TSSO8 and SO8 packages
Personal computers
Programmable controller systems
Data loggers
Automotive systems
Typical Operating Configuration
Pin Assignment
CPU
SO8
VDD
XI
XO
CS
WR
RD
Address
Decoder
V3020
VSS
I/O
CS
RD
XI
V3020
WR
I/O
TSSO8
XO
WR
VDD
RD
I/O
VSS
V3020
XI
XO
CS
CS
RD
WR
RAM
Fig. 2
www.emmicroelectronic.com
Fig. 1
Copyright © 2005, EM Microelectronic-Marin SA
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