M48T39Y 256 Kb (32K x8) TIMEKEEPER® SRAM PRELIMINARY DATA ■ INTEGRATED ULTRA LOW POWER SRAM, REAL TIME CLOCK, POWER-FAIL CONTROL CIRCUIT, BATTERY and CRYSTAL ■ BCD CODED YEAR, MONTH, DAY, DATE, HOURS, MINUTES and SECONDS ■ AUTOMATIC POWER-FAIL CHIP DESELECT and WRITE PROTECTION ■ WRITE PROTECT VOLTAGE (VPFD = Power-fail Deselect Voltage): 32 – M48T39Y: 4.20V ≤ VPFD ≤ 4.50V ■ PROGRAMMABLE INTERRUPTS and SQUARE WAVE OUTPUT ■ WATCHDOG TIMER RESTARTS on OUT-OF-CONTROL PROCESSOR ■ CLOCK ACCURACY IS BETTER THAN ±1 MINUTE per MONTH at 25°C ■ 10 YEARS of DATA RETENTION and CLOCK OPERATION in the ABSENCE of POWER ■ SELF-CONTAINED BATTERY and CRYSTAL in DIP PACKAGE ■ PROGRAMMABLE ALARM OUTPUT ACTIVE in the BATTERY BACK-UP MODE ■ PIN and FUNCTION COMPATIBLE with DS1386 DESCRIPTION The M48T39Y TIMEKEEPER ® RAM is a non-volatile 262,144 bit static RAM and real time clock organized as 32,768 words by 8 bits. System integration features include Programmable Alarms, Watchdog Timer and Interval Timer. The special 32-pin DIP package provides a highly integrated battery back-up memory and real time clock solution. 1 PMDIP32 (PM) Module Figure 1. Logic Diagram VCC 15 8 A0-A14 W DQ0-DQ7 M48Z129Y INTA E INTB G SQW VSS AI02311 January 1998 This is preliminary information on a new product now in development or undergoing evaluation. Details are subject to change without notice. 1/4 M48T39Y Figure 2. DIP Connections INTA INTB A14 A12 A7 A6 A5 A4 A3 A2 A1 A0 DQ0 DQ1 DQ2 VSS Table 1. Signal Names 32 1 31 2 30 3 29 4 28 5 27 6 26 7 25 8 M48T39Y 24 9 23 10 22 11 21 12 20 13 19 14 18 15 17 16 VCC SQW VCC W A13 A8 A9 A11 G A10 E DQ7 DQ6 DQ5 DQ4 DQ3 A0-A14 Address Inputs DQ0-DQ7 Data Inputs / Outputs E Chip Enable Input G Output Enable Input W Write Enable Input INTA Interrupt Output A (Open Drain) INTB Interrupt Output B (Open Drain) SQW Square Wave Output VCC Supply Voltage VSS Ground AI02312 Table 2. Ordering Information Scheme Example: M48T39Y -100 PM 1 Device Type M48T Supply Voltage and Write Protect Voltage 39Y = VCC = 4.5V to 5.5V; VPFD = 4.2V to 4.5V Speed -100 = 100ns -150 = 150ns Package PM = PMDIP32 Temperature Range 1 = 0 to 70 °C For a list of available options (Speed, Package, etc...) or for further information on any aspect of this device, please contact the ST Sales Office nearest to you. 2/4 M48T39Y Table 3. PMDIP32 - 32 pin Plastic Module DIP, Package Mechanical Data mm inches Symb Typ Min Max A 9.27 A1 Min Max 9.52 0.3650 0.3748 0.38 – 0.0150 – B 0.43 0.59 0.0169 0.0232 C 0.20 0.33 0.0079 0.0130 D 42.42 43.18 1.6701 1.7000 E 18.03 18.80 0.7098 0.7402 e1 2.29 2.79 0.0902 0.1098 e3 34.29 41.91 1.3500 1.6500 eA 14.99 16.00 0.5902 0.6299 L 3.05 3.81 0.1201 0.1500 S 1.91 2.79 0.0752 0.1098 N Typ 32 32 Figure 3. PMDIP32 - 32 pin Plastic Module DIP, Package Outline A A1 B S L C eA e1 e3 D N E 1 PMDIP Drawing is not to scale. 3/4 M48T39Y Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics. The ST logo is registered trademark of STMicroelectronics 1998 STMicroelectronics - All Rights Reserved All other names are the property of their respective owners. STMicroelectronics GROUP OF COMPANIES Australia - Brazil - China - Finland - France - Germany - Hong Kong - India - Italy - Japan - Malaysia - Malta - Morocco Singapore - Spain - Sweden - Switzerland - United Kingdom - U.S.A. http://www.st.com 4/4