DS1743, DS1743P Y2K-Compliant, Nonvolatile Timekeeping RAMs

Description

The DS1743 is a full-function, year-2000-compliant (Y2KC), real-time clock/calendar (RTC) and 8k x 8 nonvolatile static RAM. User access to all registers within the DS1743 is accomplished with a bytewide interface as shown in Figure 1 in the full data sheet. 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 binary-coded decimal (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 DS1743 also contains its own power-fail circuitry, which deselects the device when the V_CC supply is in an out-of-tolerance condition. When V_CC is above V_PF, the device is fully accessible. When V_CC is below V_PF, the internal active-low CE signal is forced high, preventing any access. When V_CC rises above V_PF, access remains inhibited for T_REC, allowing time for the system to stabilize. These features prevent loss of data from unpredictable system operation brought on by low V_CC as errant access and update cycles are avoided.

Key Features

Integrated NV SRAM, Real-Time Clock, Crystal, Power-Fail Control Circuit, and Lithium Energy Source
Clock Registers are Accessed Identically to the Static RAM. These Registers Reside in the Eight Top RAM Locations.
Century Byte Register
Totally Nonvolatile with Over 10 Years of Operation in the Absence of Power
BCD-Coded Century, Year, Month, Date, Day, Hours, Minutes, and Seconds with Automatic Leap Year Compensation Valid through 2099
Low-Battery-Voltage Level Indicator Flag
Power-Fail Write Protection Allows for ±10% V_CC Power-Supply Tolerance
Lithium Energy Source is Electrically Disconnected to Retain Freshness Until Power is Applied for the First Time
DIP Module Only
- Standard JEDEC Bytewide 8k x 8 Static RAM Pinout
PowerCap Module Board Only
- Surface-Mountable Package for Direct Connection to PowerCap Containing Battery and Crystal
- Replaceable Battery (PowerCap)
- Power-On Reset Output
- Pin-for-Pin Compatible with Other Densities of DS174XP Timekeeping RAM
Underwriters Laboratories (UL®) Recognized

Key Specifications: Timekeeping & Real-Time Clocks

Part Number

Time Format (hh = sec/100)

Date Format

Interface

Supply Voltage (V)

Memory Type

Memory Size (Bytes)

Number of Time of Day Alarms

Price^**

DS1743

HH:MM:SS

YYYY-MM-DD

Bytewide

3.3
5

NV SRAM

$8.78 @ 1k

See All Timekeeping & Real-Time Clocks (86)

Notes:
^**This pricing is BUDGETARY, for comparing similar parts. Prices are in U.S. dollars and subject to change. Quantity pricing may vary substantially and international prices may differ due to local duties, taxes, fees, and exchange rates. For volume-specific prices and delivery, please see the price and availability page or contact an authorized distributor.

Ordering Information

Notes:

Other options and links for purchasing parts are listed at: http://www.maxim-ic.com/sales.
Didn't Find What You Need? Ask our applications engineers. Expert assistance in finding parts, usually within one business day.
Part number suffixes: T or T&R = tape and reel; + = RoHS/lead-free; # = RoHS/lead-exempt. More: SeeFull Data Sheet or Part Naming Conventions.
* Some packages have variations, listed on the drawing. "PkgCode/Variation" tells which variation the product uses. Note that "+", "#", "-" in the part number suffix describes RoHS status. Package drawings may show a different suffix character.

Devices: 1-25 of 25

DS1743

Free
Sample

Buy

Package:	TYPE PINS FOOTPRINT
	DRAWING CODE/VAR *

Temp

RoHS/Lead-Free?
Materials Analysis

DS1743-85+

0 pin;

Use pkgcode/variation: MDF28+2*

0°C to +70°C

RoHS/Lead-Free: Lead Free
Materials Analysis

DS1743-85IND+

0 pin;

Use pkgcode/variation: MDF28+2*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

DS1743-100

0 pin;

Use pkgcode/variation: MDF28-2*

0°C to +70°C

RoHS/Lead-Free: No
Materials Analysis

DS1743W-120+

0 pin;

Use pkgcode/variation: MDF28+2*

0°C to +70°C

RoHS/Lead-Free: Lead Free
Materials Analysis

DS1743W-120IND+

0 pin;

Use pkgcode/variation: MDF28+2*

0°C to +70°C

RoHS/Lead-Free: Lead Free
Materials Analysis

DS1743W-150+

0 pin;

Use pkgcode/variation: MDF28+2*

0°C to +70°C

RoHS/Lead-Free: Lead Free
Materials Analysis

DS1743W-150

0 pin;

Use pkgcode/variation: MDF28-2*

0°C to +70°C

RoHS/Lead-Free: No
Materials Analysis

DS1743W-120

0 pin;

Use pkgcode/variation: MDF28-2*

0°C to +70°C

RoHS/Lead-Free: No
Materials Analysis

DS1743-100+

0 pin;

Use pkgcode/variation: MDF28+2*

0°C to +70°C

RoHS/Lead-Free: Lead Free
Materials Analysis

DS1743W-120 IND

0 pin;

Use pkgcode/variation: MDF28-2*

-40°C to +85°C

RoHS/Lead-Free: No
Materials Analysis

DS1743-100 IND

0 pin;

Use pkgcode/variation: MDF28-2*

-40°C to +85°C

RoHS/Lead-Free: No
Materials Analysis

DS1743-100IND+

0 pin;

Use pkgcode/variation: MDF28+2*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

DS1743WP-120IND+

0 pin;

Use pkgcode/variation: PC1+2*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

DS1743WP-150+

0 pin;

Use pkgcode/variation: PC1+2*

0°C to +70°C

RoHS/Lead-Free: Lead Free
Materials Analysis

DS1743WP-120+

0 pin;

Use pkgcode/variation: PC1+2*

0°C to +70°C

RoHS/Lead-Free: Lead Free
Materials Analysis

DS1743WP-120

0 pin;

Use pkgcode/variation: PC1-2*

0°C to +70°C

RoHS/Lead-Free: No
Materials Analysis

DS1743WP-150

0 pin;

Use pkgcode/variation: PC1-2*

0°C to +70°C

RoHS/Lead-Free: No
Materials Analysis

DS1743WP-120IND

0 pin;

Use pkgcode/variation: PC1-2*

-40°C to +85°C

RoHS/Lead-Free: No
Materials Analysis

DS1743P

Free
Sample

Buy

Package:	TYPE PINS FOOTPRINT
	DRAWING CODE/VAR *

Temp

RoHS/Lead-Free?
Materials Analysis

DS1743P-85+

0 pin;

Use pkgcode/variation: PC1+2*

0°C to +70°C

RoHS/Lead-Free: Lead Free
Materials Analysis

DS1743P-C01+

0 pin;

Use pkgcode/variation: PC1+2*

0°C to +70°C

RoHS/Lead-Free: Lead Free
Materials Analysis

DS1743P-85IND+

0 pin;

Use pkgcode/variation: PC1+2*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

DS1743P-100+

0 pin;

Use pkgcode/variation: PC1+2*

0°C to +70°C

RoHS/Lead-Free: Lead Free
Materials Analysis

DS1743P-100IND

0 pin;

Use pkgcode/variation: PC1-2*

0°C to +70°C

RoHS/Lead-Free: No
Materials Analysis

DS1743P-100IND+

0 pin;

Use pkgcode/variation: PC1+2*

0°C to +70°C

RoHS/Lead-Free: Lead Free
Materials Analysis

DS1743P-100

0 pin;

Use pkgcode/variation: PC1-2*

0°C to +70°C

RoHS/Lead-Free: No
Materials Analysis