Rainbow Electronics MAX6901 - Manual

General Description
The MAX6901 3-wire serial interface real-time clock in a
TDFN package contains a real-time clock/calendar and
31 x 8 bits of static RAM (SRAM). The real-time
clock/calendar provides seconds, minutes, hours, day,
date, month, year, and century information. A
time/date-programmable polled ALARM is included in
the MAX6901. The end of the month date is automati-
cally adjusted for months with fewer than 31 days,
including corrections for leap year up to the year 2100.
The clock operates in either the 24hr or 12hr format
with an AM/PM indicator. A push-pull 32kHz output is
also included. The MAX6901 operates with a supply
voltage of +2V to +5.5V, is available in the ultra-small 8-
pin TDFN package, and works over the industrial tem-
perature range, -40°C to +85°C.
Applications
Point-of-Sale Equipment
Intelligent Instruments
Fax Machines
Battery-Powered Products
Portable Instruments
Features
♦ Real-Time Clock Counts Seconds, Minutes,
Hours, Day of Week, Date of Month, Month, Year,
and Century
♦ Leap-Year Compensation Valid up to Year 2100
♦ Wide +2V to +5.5V Operating Voltage Range
♦ 3-Wire Serial Interface, 2MHz at 5V, 500kHz at 2V
♦ 31 x 8-Bit SRAM for Scratchpad Data Storage
♦ Uses Standard 32.768kHz, 12.5pF Watch Crystal
♦ Low Timekeeping Current (400nA at 2V)
♦ Single-Byte or Multiple-Byte (Burst Mode)
Data Transfer for Read or Write of Clock
Registers or SRAM
♦ 8-Pin 3mm x 3mm x 0.8mm TDFN
Surface-Mount Package
♦ Push-Pull 32.768kHz Clock Output
♦ Programmable Time/Date Polled ALARM Function
♦ No External Crystal Bias Resistors or Capacitors
Required
MAX6901
3-Wire Serial RTC in a TDFN
________________________________________________________________ Maxim Integrated Products 1
19-2085; Rev 1; 2/03
Ordering Information
PART
TEMP
RANGE
PIN-
PACKAGE TOP
MARK
MAX6901ETA-T -40 °C to +85°C 8 TDFN AGV
Related Real-Time Clock Products
PART
SERIAL
INTERFACE
ALARM
(bits)
ALARM
FUNCTION
OUTPUT
FREQUENCY
PIN-PACKAGE
MAX6900 I 2 C™ compatible 31 x 8 — — 6 TDFN
MAX6901 3 wire 31 x 8 Polled 32kHz 8 TDFN
MAX6902 SPI ™ compatible 31 x 8 Polled — 8 TDFN
Pin Configuration appears at end of data sheet.
Functional Diagram appears at end of data sheet.
µC
0.1 µF
32.768kHz
CRYSTAL
1
4
3
6
2
5
3.3V
3.3V
MAX6901
7
8
P1.0
CLKIN
P1.1
P1.2
SCLK
CS
I/O
32KHZ
GND
V
CC X1
X2
Typical Operating Circuit
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
I 2 C is a trademark of Philips Corp. Purchase of I 2 C components of Maxim Integrated Products, Inc., or one of its sublicensed Associated
Companies, conveys a license under the Philips I 2 C Patent rights to use these components in an I 2 C system provided that the system
conforms to the I 2 C Standard Specification as defined by Philips.
SPI is a trademark of Motorola, Inc.