My Inquiry
My Account
STMicroelectronics M48T37V-10MH1E
- Part No.:
- M48T37V-10MH1E
- Manufacturer:
- STMicroelectronics
- Category:
- Real Time Clocks
- Package:
- 44-BSOP (0.337", 8.56mm Width) requires SNAPHAT
- Datasheet:
-
M48T37V-10MH1E.pdf
- Description:
- IC RTC CLK/CALENDAR PAR 44SOH
- Quantity:
- Payment:
- Shipping:
Inventory:4,185
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
M48T37V-10MH1E from STMicroelectronics is a 32 K × 8 (256 Kbit) battery-backed TIMEKEEPER® SRAM integrating real-time clock, watchdog timer, power-fail control, and microprocessor reset-operating at 3.0–3.6 V with VPFD = 2.7–3.0 V and 7-year data retention on internal lithium battery. It delivers BCD-formatted time/date registers (century, year, month, day, hour, minute, second), alarm interrupt, and frequency test output for software calibration in embedded industrial control and metering systems.
For engineers reviewing the M48T37V-10MH1E datasheet, M48T37V-10MH1E pinout, M48T37V-10MH1E application, or M48T37V-10MH1E equivalent, key selection criteria include VCC range compatibility (3.0–3.6 V), SNAPHAT®-compatible SOH44 package integration, battery-backed RTC accuracy (±20 ppm over –40°C to +85°C), and WRITE protection behavior during power fail.
Technical Context
The M48T37V-10MH1E integrates a 32,768 Hz crystal oscillator, BiPORT™ SRAM array, voltage-sense switching circuitry, and clock chain on a single die. Its RTC updates BCD time registers (7FF1h–7FFFh) once per second while maintaining full SRAM access via standard parallel interface.
Power management includes automatic switchover to internal lithium battery at VSO (2.5 V typical), VPFD-triggered write protection (2.7–3.0 V), and CMOS standby mode with <1 μA current draw. The IRQ/FT pin serves dual function: alarm interrupt (active-low, battery-backup enabled) and frequency test output for calibration.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Memory size | 32 K × 8 (256 Kbit) non-volatile SRAM with BYTEWIDE™ access |
| VCC operating range | 3.0 V to 3.6 V - defines system supply compatibility for 3.3 V logic domains |
| VPFD range | 2.7 V ≤ VPFD ≤ 3.0 V - precise voltage window triggering automatic WRITE protect during brownout |
| Data retention | ≥7 years at 25°C on internal lithium battery - eliminates external backup power design |
| RTC accuracy | ±20 ppm over –40°C to +85°C - enables reliable timestamping without external calibration |
| Access time | 100 ns max (M48T37V grade) - supports 10 MHz bus timing in microcontroller interfaces |
| Alarm capability | Programmable daily/hourly/minute/second alarm with battery-backup activation - enables low-power wake-up events |
Pinout & Package
Package: 44-pin SOIC (SOH44) with gold-plated top/bottom sockets for direct mating with SNAPHAT® housing (e.g., M4T28-BR12SH) containing 32.768 kHz crystal and lithium coin cell. SNAPHAT® mounts post-reflow to avoid thermal damage.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| A0–A14 | Address inputs | 15-bit address bus selecting one of 32,752 SRAM locations or 16 RTC register addresses |
| DQ0–DQ7 | Data I/O | Bi-directional 8-bit data bus for SRAM read/write and RTC register access |
| E | Chip enable | Active-low signal enabling memory access; high-Z state during power-fail deselect |
| G | Output enable | Controls DQ0–DQ7 output drivers independently of E; prevents bus contention during partial cycles |
| W | WRITE enable | Active-low signal initiating WRITE cycle; combined with E determines write timing and bus direction |
| RST | Reset output | Open-drain active-low reset pulse generated on power-on or watchdog timeout |
| IRQ/FT | Interrupt / Frequency test | Open-drain output: alarm interrupt (low-active) or 32.768 kHz square wave for software calibration |
| WDI | Watchdog input | Edge-sensitive input resetting watchdog timer; failure to toggle causes RST assertion |
| VCC | Supply voltage | 3.0–3.6 V main power; monitored continuously for VPFD/VSO thresholds |
| VSS | Ground | Reference return for all analog/digital circuits including RTC oscillator and voltage sense |
Key Features
| Feature | Design Value |
|---|---|
| Integrated RTC + SRAM + battery + crystal | Single-component solution eliminating discrete backup power, oscillator, and timekeeping ICs |
| SNAPHAT®-ready SOH44 package | Enables surface-mount assembly before battery/crystal installation-prevents reflow damage |
| Programmable alarm in battery backup mode | Allows system wake-up from deep sleep without main power, reducing overall energy consumption |
| Microprocessor power-on reset (battery-backed) | Valid reset pulse generated even during VCC loss-ensures deterministic boot after brownout recovery |
| Battery low flag (BL) | Read-only status bit alerts firmware of end-of-life battery condition before data retention fails |
Applications
| Industrial PLCs | Smart Electricity Meters |
|---|---|
Use Scenario: Maintaining accurate timestamps and operational logs during grid outages or brownouts. IC Role / Device Role / Timing Role: Battery-backed RTC and non-volatile SRAM storing event logs, tariff schedules, and firmware configuration. Use Value: Ensures regulatory-compliant time-stamped billing data remains intact for ≥7 years without external backup components. |
Use Scenario: Recording energy consumption and tamper events across extended power interruptions. IC Role / Device Role / Timing Role: Real-time clock with alarm-driven wake-up and secure SRAM storage for metering registers and security keys. Use Value: Eliminates need for external RTC, backup capacitor, and discrete watchdog-reducing BOM count and PCB area by 3+ components. |
| Medical Infusion Pumps | Building Automation Controllers |
Use Scenario: Logging therapy delivery history and calibration timestamps under intermittent AC power or battery operation. IC Role / Device Role / Timing Role: Timekeeping and non-volatile memory for FDA-required audit trails and device uptime tracking. Use Value: Provides traceable, battery-backed time stamps meeting IEC 62304 software lifecycle requirements without external clock source. |
Use Scenario: Scheduling HVAC cycles and logging occupancy sensor events during building-wide power dips. IC Role / Device Role / Timing Role: RTC with programmable alarm interrupt driving scheduled operations and SRAM storing schedule tables and sensor history. Use Value: Enables deterministic time-based control execution independent of host MCU power state-critical for fail-safe building safety logic. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar battery-backed RTC+SRAM applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| DS1742W-120+ (Maxim Integrated) | 5 V only (4.5–5.5 V); no watchdog timer; uses external crystal; 10-year retention | Requires level-shifting for 3.3 V systems; lacks integrated alarm interrupt and frequency test output | Select if legacy 5 V design exists and watchdog functionality is unnecessary |
| PCF2129AT/1 (NXP) | I²C interface only; no parallel SRAM; 3.0–5.5 V; 10-year retention; integrated crystal | Cannot replace parallel-memory functions; requires firmware rewrite for serial communication | Choose only when redesigning for lower pin count and accepting loss of SRAM capacity |
Compared with DS1742W-120+ and PCF2129AT/1, the M48T37V-10MH1E uniquely combines 3.3 V parallel SRAM, integrated watchdog, alarm interrupt, and SNAPHAT®-enabled modular packaging-making it irreplaceable in space-constrained, battery-backed industrial controllers requiring deterministic timing and memory access.
Availability
M48T37V-10MH1E is available at Aetrix Electronics and suitable for industrial PLCs, smart electricity meters, medical infusion pumps, and building automation controllers requiring stable component supply with long-term lifecycle support.
Supply support for M48T37V-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 microcontrollers, power management ICs, sensors, and timing solutions for industrial, automotive, and consumer markets.
The M48T37V-10MH1E belongs to ST's TIMEKEEPER® family-engineered specifically for mission-critical applications demanding guaranteed timekeeping, non-volatile memory, and autonomous power-fail response without external supervision.
FAQ
What is the purpose of the SNAPHAT® housing, and is it included with M48T37V-10MH1E?
The SNAPHAT® housing (e.g., M4T28-BR12SH) contains the 32.768 kHz crystal and lithium coin cell battery, and mounts directly onto the SOH44 package after reflow soldering to prevent thermal damage. It is not included with M48T37V-10MH1E-the SOIC and SNAPHAT® are shipped separately in anti-static tubes or tape-and-reel format per ST's ordering scheme.
How does the M48T37V-10MH1E handle power transitions between VCC and battery backup?
When VCC drops below VSO (~2.5 V), the internal switch connects the lithium battery to maintain SRAM and RTC operation. At VPFD (2.7–3.0 V), WRITE protection activates automatically. Upon VCC recovery above VPFD(max), normal operation resumes after tREC (100 ms typical), with no data corruption if power failure duration stays within specification limits.
Can the alarm function operate while the main system power is off?
Yes-the alarm is fully functional in battery backup mode. When enabled via ABE bit (register 7FF6h), the alarm generates an active-low pulse on IRQ/FT even with VCC = 0 V, allowing wake-up of external circuitry or microcontroller from deep sleep without main power.
What is the significance of the "10MH1E" suffix in the part number?
"10" indicates 100 ns maximum access time; "M" denotes SOH44 package; "H" specifies SNAPHAT®-compatible top-socket version; "1" is revision code; "E" signifies RoHS-compliant, lead-free second-level interconnect-fully aligned with ST's Doc ID 7019 Rev 9 specification.
M48T37V-10MH1E Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Series:
- Timekeeper®
- Package/Case:
- 44-BSOP (0.337", 8.56mm Width) requires SNAPHAT
- Packaging:
- Tube
- Product Status:
- Obsolete
- Programmable:
- Not Verified
- Type:
- Clock/Calendar
- Features:
- Alarm, Leap Year, Watchdog Timer
- Memory Size:
- -
- Time Format:
- HH:MM:SS (24 hr)
- Date Format:
- YY-MM-DD-dd
- Interface:
- Parallel
- Voltage - Supply:
- 3V ~ 3.6V
- Voltage - Supply, Battery:
- -
- Current - Timekeeping (Max):
- 2mA @ 3V ~ 3.6V
- Operating Temperature:
- 0°C ~ 70°C
- Mounting Type:
- Surface Mount
- Grade:
- -
- Qualification:
- -
- Supplier Device Package:
- 44-SOH
M48T37V-10MH1E FAQ
1.How can I place an order for M48T37V-10MH1E through Aetrix?
Please submit a Request for Quotation (RFQ) for M48T37V-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 M48T37V-10MH1E reliable?
The price and inventory of M48T37V-10MH1E are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for M48T37V-10MH1E is usually 5 days.
3.What payment methods are accepted for M48T37V-10MH1E?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for M48T37V-10MH1E transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for M48T37V-10MH1E?
M48T37V-10MH1E orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your M48T37V-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 M48T37V-10MH1E?
For technical support, including M48T37V-10MH1E datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your M48T37V-10MH1E requirements.
6.How does Aetrix verify that M48T37V-10MH1E is sourced from the original manufacturer or authorized distributors?
All M48T37V-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 M48T37V-10MH1E meets industry standards.
7.What is the process for return or replacement of M48T37V-10MH1E?
All M48T37V-10MH1E units undergo pre-shipment inspection (PSI). If there is an issue with M48T37V-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 M48T37V-10MH1E part is unused and in its original packaging.
Return procedure for M48T37V-10MH1E:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
M48T37V-10MH1E Tags
-
MCP7940N-I/SN
Microchip Technology
-
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
Tech Hub
A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.
TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
