Inicio > Circuitos integrados IC > DS12CR887-33+

DS12CR887-33+

RTC with integrated crystal, 114B+4KB SRAM, 3 alarms, EDIP-24, bus interface

8365

Inventario efectivo

Ir a la consulta

Image for reference only

Pieza del fabricante：

DS12CR887-33+

Paquete：

EDIP-24 (30.48 x 15.24 x 16.00 mm) with integrated crystal

Marca：

Categorías de productos：

Circuitos integrados IC, Circuitos integrados de interfaz

Otras recomendaciones que pueden interesarle.

SII9396SCNUC-BAR

IS43TR16256BL-125KBLI

Descripción

Productos

The DS12CR887-33+ from Maxim Integrated (Analog Devices) is a real-time clock with integrated crystal, 114 bytes of battery-backed SRAM, and 4KB of extended SRAM in an EDIP-24 package. The on-chip crystal eliminates external crystal requirements.

Especificaciones

Interface	Multiplexed Motorola/Intel bus
Time/Date	Seconds through year with century
SRAM	114 bytes (battery-backed) + 4KB extended
Crystal	Integrated 32.768kHz
Alarms	3 programmable
Tensión de alimentación	4.5 V to 5.5 V
Temperatura de funcionamiento	0C to +70C

Características

Integrated 32.768kHz crystal eliminates external component
114 bytes of battery-backed SRAM plus 4KB extended SRAM
Three programmable alarms with interrupt output
Motorola and Intel bus timing compatible
Daylight saving adjustment

Aplicaciones

PC real-time clock with battery backup
Embedded system timekeeping with bus interface
Data logging with 4KB extended SRAM
Industrial controller timestamps

Introducción del producto:DS12CR887-33+ Presentación del producto

The DS12CR887-33+ from Maxim Integrated (Analog Devices) is a real-time clock with an integrated 32.768kHz crystal in an EDIP-24 package. The device provides complete time and date functions including seconds, minutes, hours, day, date, month, year, and century with automatic leap year correction and daylight saving adjustment. It includes 114 bytes of battery-backed general-purpose SRAM and 4KB of extended SRAM for data storage. Three programmable alarms with interrupt output support complex scheduling. The parallel bus interface supports both Motorola and Intel timing modes for direct connection to microprocessor buses. The integrated crystal simplifies PCB design by eliminating external crystal and load capacitors.

Principio de funcionamiento:DS12CR887-33+ Principio de funcionamiento

The DS12CR887-33+ integrates RTC, crystal, SRAM, and bus interface in a single module. (1) Oscillator: The integrated 32.768kHz crystal oscillator provides the timebase. The crystal is encapsulated within the package with trimming capacitors, eliminating external components and ensuring reliable startup. (2) RTC: The oscillator drives a counter chain that maintains time and date registers. Century tracking and automatic leap year correction are handled in hardware. (3) Bus Interface: A parallel multiplexed address/data bus connects to microprocessor buses. The bus supports both Motorola (DS, R/W) and Intel (RD, WR) timing modes selected via the MOT pin. (4) Battery Backup: An internal lithium cell or external battery maintains timekeeping and SRAM contents when VCC is removed. The internal cell provides approximately 10 years of backup time. (5) Alarms: Three alarm registers can be set for time-of-day, day-of-week, or periodic interrupts.

Descripción de la clavija:DS12CR887-33+ Definición y funciones de las clavijas

Grupo Pin	Nombre	Tipo	Función
1-8	AD0-AD7	E/S	Multiplexed address/data bus
9	CS	Entrada	Chip select (active low)
10	AS	Entrada	Address strobe (Motorola) / ALE (Intel)
11	R/W or WR	Entrada	Read/Write (Motorola) / Write (Intel)
12	DS or RD	Entrada	Data strobe (Motorola) / Read (Intel)
13	RESET	Entrada	Reset (active low)
14	IRQ	Salida	Interrupt request (active low)
15	SQW	Salida	Square wave output (programmable)

Application Scenarios:In which products and applications isDS12CR887-33+ usado

PC and embedded system real-time clock with integrated crystal
Data logging systems with 4KB extended SRAM for event records
Industrial controller timestamps with parallel bus interface
Scheduling systems with three independent alarms

Alternative Models:What chips are recommended as replacements for DS12CR887-33+

Fabricante	Número de pieza	Paquete	Notas
Maxim	DS12887+	EDIP-24	Original version, no extended SRAM
Maxim	DS12B887+	EDIP-24	Binary-compatible, enhanced
Microchip	MCP79410	SOIC-8	I2C RTC, smaller, no integrated crystal
Maxim	DS3231SN#	SOIC-16	TCXO I2C RTC, higher accuracy