DS1742-100 Maxim Integrated Products, DS1742-100 Datasheet - Page 2

• Manufacturer Part Number: DS1742-100
• Description: IC RTC RAM Y2K 5V 100NS 24-EDIP
• Manufacturer: Maxim Integrated Products
• Type: Clock/Calendar/NVSRAM/Y2Kr

Specifications of DS1742-100

• Memory Size: 16K (2K x 8)
• Time Format: HH:MM:SS (24 hr)
• Date Format: YY-MM-DD-dd
• Interface: Parallel
• Voltage - Supply: 4.5 V ~ 5.5 V
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Through Hole
• Package / Case: 24-DIP (600 mil) Module
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

PIN DESCRIPTION
DESCRIPTION
The DS1742 is a full-function, year 2000-compliant (Y2KC), real-time clock/calendar (RTC) and
2k x 8 nonvolatile static RAM. User access to all registers within the DS1742 is accomplished
with a bytewide interface as shown in Figure 1. The RTC information and control bits reside in
the eight uppermost RAM locations. The RTC registers contain century, year, month, date, day,
hours, minutes, and seconds data in 24-hour BCD format. Corrections for the day of the month
and leap year are made automatically.
The RTC clock registers are double-buffered to avoid access of incorrect data that can occur
during clock update cycles. The double-buffered system also prevents time loss as the
timekeeping countdown continues unabated by access to time register data. The DS1742 also
contains its own power-fail circuitry, which deselects the device when the V
out-of-tolerance condition. This feature prevents loss of data from unpredictable system
operation brought on by low V
PIN
19
22
23
10
11
13
14
15
16
17
12
18
20
21
24
1
2
3
4
5
6
7
8
9
NAME
GND
DQ0
DQ1
DQ2
DQ3
DQ4
DQ5
DQ6
DQ7
A10
WE
V
CE
OE
A7
A6
A5
A4
A3
A2
A1
A0
A9
A8
CC
Address Input
Data Input/Output
Ground
Power-Supply Input
Active-Low Chip-Enable Input
Active-Low Output-Enable Input
Active-Low Write-Enable Input
CC
as errant access and update cycles are avoided.
FUNCTION
2 of 16
CC
supply is in an
DS1742