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STMicroelectronics M48T08Y-10MH1E
- Part No.:
- M48T08Y-10MH1E
- Manufacturer:
- STMicroelectronics
- Category:
- Real Time Clocks
- Package:
- 28-SOP (0.350", 8.89mm Width) with SNAPHAT Sockets
- Datasheet:
-
M48T08Y-10MH1E.pdf
- Description:
- IC RTC CLK/CALENDAR PAR 28SOH
- Quantity:
- Payment:
- Shipping:
Inventory:2,827
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Product details
Overview
M48T08Y-10MH1E from STMicroelectronics is a 64 Kbit (8 Kb × 8) non-volatile TIMEKEEPER® SRAM integrating ultra-low-power static RAM, real-time clock, power-fail control circuitry, and on-board lithium battery + 32.768 kHz crystal in CAPHAT™ DIP package. It delivers ±1 minute/month clock accuracy at 25 °C, supports BYTEWIDE™ RAM-like access to BCD-coded time registers (year/month/day/hour/minute/second), and provides automatic WRITE protection during VCC drop below 4.2 V. Used in industrial control panels for persistent timestamping of event logs under intermittent power.
For engineers reviewing the M48T08Y-10MH1E datasheet, M48T08Y-10MH1E pinout, M48T08Y-10MH1E application, or M48T08Y-10MH1E equivalent, this page details its integrated RTC+SRAM architecture, battery-backed data retention behavior, VPFD voltage thresholds, INT interrupt timing, and compatibility with DS1643 and JEDEC 8K×8 SRAM sockets.
Technical Context
The device integrates a BiPORT™ SRAM array (8184 × 8) with dedicated upper 8-byte memory-mapped registers (1FF8h–1FFFh) storing BCD-formatted time/date values updated once per second by an internal oscillator. Clock calibration is software-controlled via the control register's CAL bits, enabling fine-tuning of oscillator frequency.
Its power management includes dual-threshold voltage sensing: VPFD (4.2–4.5 V) triggers automatic chip deselect and WRITE protection, while VSO (≈4.0 V) initiates seamless switchover to internal lithium battery, sustaining RTC and SRAM operation for ≥10 years. The open-drain INT pin asserts within 10–40 µs of VCC crossing VPFD.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Memory size | 64 Kbit (8 Kb × 8); provides byte-addressable non-volatile storage without external backup components. |
| RTC accuracy | ±1 minute/month at 25 °C; enables long-term timestamping without periodic manual correction. |
| VPFD range | 4.2 V to 4.5 V; defines precise voltage window for automatic WRITE protect activation during brownout. |
| Access time | 100 ns (min); ensures compatibility with legacy 8K×8 SRAM bus timing in microcontroller systems. |
| Battery life | ≥10 years in data retention mode; eliminates field replacement of backup power in sealed enclosures. |
| Package type | PCDIP28 CAPHAT™; integrates silicon, crystal, and 48 mAh lithium cell in single through-hole DIP footprint. |
| Interface protocol | Parallel SRAM-compatible (E1/E2/G/W/A0–A12/DQ0–DQ7); requires no I²C/SPI controller or firmware overhead. |
Pinout & Package
PCDIP28 CAPHAT™ package: 28-pin plastic DIP (600 mil width) with integrated lithium button cell and 32.768 kHz quartz crystal housed in molded cap. No external battery or crystal required.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| A0–A12 | Address inputs | 13-bit address bus for accessing 8,192 bytes of SRAM and 8-byte TIMEKEEPER registers. |
| DQ0–DQ7 | Data I/O | Bi-directional 8-bit data bus; supports BYTEWIDE™ read/write of time registers as memory locations. |
| E1, E2 | Chip enable inputs | Dual CE logic enables compatibility with JEDEC-standard 8K×8 SRAM timing and socket designs. |
| G | Output enable | Controls three-state output drivers; high-Z state prevents bus contention during WRITE or standby. |
| W | WRITE enable | Active-low signal initiating WRITE cycles; falling edge synchronizes data latch timing. |
| INT | Power-fail interrupt | Open-drain output asserting within 10–40 µs of VCC crossing VPFD; requires external pull-up. |
| VCC | Supply voltage | Single 4.5–5.5 V rail; powers SRAM and RTC; monitored continuously for VPFD/VSO detection. |
| VSS | Ground | Reference return path for all digital and analog circuitry including oscillator and voltage sense. |
Key Features
| Feature | Design Value |
|---|---|
| Integrated CAPHAT™ package | Eliminates external crystal, battery, and holder - reduces PCB area and assembly steps in space-constrained designs. |
| Memory-mapped RTC registers | Time/date stored in standard SRAM addresses (1FF8h–1FFFh), enabling direct CPU read/write without custom drivers. |
| Software clock calibration | CAL bits in control register allow ±128 ppm adjustment of oscillator frequency for high-accuracy applications. |
| Automatic power-fail response | Hardware-level WRITE protection and battery switchover occur without CPU intervention or firmware latency. |
| Leap-year compensation | Hardware auto-corrects day-of-month for February 28/29/30/31 across all months, valid until year 2100. |
Applications
| Industrial HMI Loggers | Medical Device Event Recorders |
|---|---|
|
Use Scenario: Standalone panel PC in factory floor environment records operator actions and alarm events with precise timestamps. IC Role / Device Role / Timing Role: Non-volatile SRAM stores log entries; integrated RTC supplies accurate wall-clock timestamps independent of host CPU uptime. Use Value: Maintains synchronized time and log integrity during mains outages or system reboots, eliminating timestamp gaps or resets. |
Use Scenario: Portable infusion pump logs drug delivery start/stop times, dosage, and error conditions for regulatory audit trails. IC Role / Device Role / Timing Role: Provides tamper-resistant, battery-backed timekeeping and secure parameter storage across power cycles. Use Value: Ensures FDA-compliant traceability with guaranteed ≥10-year timestamp continuity even if main battery is depleted. |
| Energy Meter Firmware Storage | Telecom Base Station Alarms |
|
Use Scenario: Smart electricity meter retains firmware configuration and tariff schedules during grid brownouts. IC Role / Device Role / Timing Role: Stores critical settings in SRAM; RTC tracks billing periods and demand intervals with calendar-aware accuracy. Use Value: Prevents loss of time-sensitive tariff data and maintains correct billing cycle alignment after extended power loss. |
Use Scenario: Cellular base station reports hardware faults and temperature excursions with precise UTC-aligned timestamps. IC Role / Device Role / Timing Role: Supplies stable time reference for SNMP trap generation and remote diagnostics logging. Use Value: Enables correlation of distributed alarms across network nodes without reliance on NTP synchronization. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar non-volatile RTC+SRAM applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| DS1643-100+ (Maxim) | Same pinout and function, but uses external crystal and separate battery; no integrated CAPHAT™ package. | Requires additional board space and two extra components; lacks factory-calibrated oscillator accuracy. | Select when redesigning legacy DS1643-based boards and external component sourcing is preferred. |
| M48T35Y-10MH1E (STMicro) | Higher density (256 Kbit SRAM), same CAPHAT™ package and RTC features; VPFD range identical (4.2–4.5 V). | Supports larger firmware/data buffers; identical footprint allows drop-in upgrade where memory expansion is needed. | Select when future-proofing for increased log depth or parameter storage without changing PCB layout. |
Compared with DS1643-100+, M48T08Y-10MH1E reduces BOM count and improves time accuracy via factory-integrated crystal; compared with M48T35Y-10MH1E, it offers lower cost and smaller footprint for applications needing only 64 Kbit.
Availability
M48T08Y-10MH1E is available at Aetrix Electronics and suitable for industrial HMI loggers, medical device event recorders, and energy meter firmware storage requiring stable component supply, long-lifecycle support, and guaranteed CAPHAT™ package integrity.
Supply support for M48T08Y-10MH1E includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing analog, MCU, power, and memory solutions for industrial, automotive, and consumer markets.
M48T08Y belongs to ST's TIMEKEEPER® family - engineered specifically for embedded systems requiring autonomous, battery-backed real-time clocking and non-volatile data storage without external timing components.
FAQ
What is the battery chemistry and capacity in the CAPHAT™ package?
The M48T08Y-10MH1E PCDIP28 CAPHAT™ package contains a 48 mAh lithium manganese dioxide (Li-MnO₂) button cell, rated for ≥10 years of data retention at 25 °C when VCC remains below VSO. This chemistry provides stable voltage discharge and low self-discharge, ensuring reliable long-term backup without maintenance.
How does the READ bit in the control register affect RTC operation?
Writing '1' to the READ bit (bit 7 of address 1FF8h) halts updates to the BCD time registers (1FF9h–1FFFh), freezing their values for safe readout without risk of reading mid-update. The underlying oscillator and counters continue running uninterrupted; register updates resume automatically one second after writing '0' to the READ bit.
Can the M48T08Y-10MH1E operate without the INT pin connected?
Yes - the INT pin is optional. It is an open-drain output requiring an external pull-up resistor only if power-fail interrupt signaling is used. If unused, the pin may be left unconnected; the device still performs automatic WRITE protection and battery switchover regardless of INT status.
Is the M48T08Y-10MH1E RoHS compliant and lead-free?
Yes - the M48T08Y-10MH1E is RoHS compliant with lead-free second-level interconnects, meeting EU Directive 2011/65/EU. Its PCDIP28 CAPHAT™ package uses matte tin plating on leads and conforms to JEDEC J-STD-020 moisture sensitivity level (MSL) 3 for surface-mount handling.
M48T08Y-10MH1E Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Series:
- Timekeeper®
- Package/Case:
- 28-SOP (0.350", 8.89mm Width) with SNAPHAT Sockets
- Packaging:
- Tube
- Product Status:
- Obsolete
- Programmable:
- Not Verified
- Type:
- Clock/Calendar
- Features:
- Leap Year, Watchdog Timer
- Memory Size:
- -
- Time Format:
- HH:MM:SS (24 hr)
- Date Format:
- YY-MM-DD-dd
- Interface:
- Parallel
- Voltage - Supply:
- 4.5V ~ 5.5V
- Voltage - Supply, Battery:
- -
- Current - Timekeeping (Max):
- 3mA @ 4.5V ~ 5.5V
- Operating Temperature:
- 0°C ~ 70°C
- Mounting Type:
- Surface Mount
- Grade:
- -
- Qualification:
- -
- Supplier Device Package:
- 28-SOH
M48T08Y-10MH1E FAQ
1.How can I place an order for M48T08Y-10MH1E through Aetrix?
Please submit a Request for Quotation (RFQ) for M48T08Y-10MH1E on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for M48T08Y-10MH1E reliable?
The price and inventory of M48T08Y-10MH1E are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for M48T08Y-10MH1E is usually 5 days.
3.What payment methods are accepted for M48T08Y-10MH1E?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for M48T08Y-10MH1E transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for M48T08Y-10MH1E?
M48T08Y-10MH1E orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your M48T08Y-10MH1E order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for M48T08Y-10MH1E?
For technical support, including M48T08Y-10MH1E datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your M48T08Y-10MH1E requirements.
6.How does Aetrix verify that M48T08Y-10MH1E is sourced from the original manufacturer or authorized distributors?
All M48T08Y-10MH1E products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that M48T08Y-10MH1E meets industry standards.
7.What is the process for return or replacement of M48T08Y-10MH1E?
All M48T08Y-10MH1E units undergo pre-shipment inspection (PSI). If there is an issue with M48T08Y-10MH1E, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The M48T08Y-10MH1E part is unused and in its original packaging.
Return procedure for M48T08Y-10MH1E:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
M48T08Y-10MH1E Tags
-
MCP7940N-I/SN
Microchip Technology
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MCP7940MT-I/MNY
Microchip Technology
-
PCF85063ATL/1,118
NXP USA Inc.
-
MCP7940NT-I/SN
Microchip Technology
-
MCP7940NT-I/MS
Microchip Technology
-
MCP7940N-I/MS
Microchip Technology
-
PCF85063AT/AY
NXP USA Inc.
-
PCF85063TP/1Z
NXP Semiconductors
-
PCF85063ATT/AJ
NXP USA Inc.
-
MCP7940NT-E/SN
Microchip Technology
-
MCP7940NT-I/MNY
Microchip Technology
-
MCP79400T-I/SN
Microchip Technology
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