DS1742-70 Maxim Integrated Products, DS1742-70 Datasheet - Page 2

• Manufacturer Part Number: DS1742-70
• Description: IC RTC RAM Y2K 5V 70NS 24-EDIP
• Manufacturer: Maxim Integrated Products
• Type: Clock/Calendar/NVSRAM/Y2Kr

Specifications of DS1742-70

• 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
loss of data from unpredictable system operation brought on by low V
cycles are avoided.
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
Active-Low Chip-Enable Input
Active-Low Output-Enable Input
Active-Low Write-Enable Input
Power-Supply Input
CC
supply is in an out-of-tolerance condition. This feature prevents
FUNCTION
2 of 15
CC
as errant access and update