Overview
The M48T201V-85MH1F, produced by STMicroelectronics, is a self-contained TIMEKEEPER® supervisor device. It integrates a real-time clock (RTC), programmable alarms, a watchdog timer, and a square wave output. This device is designed to control up to 512 K x 8 of external low-power static RAM and provides access to all RTC functions and external RAM similar to conventional byte-wide SRAM. The 16 TIMEKEEPER® registers store data such as year, month, date, day, hour, minute, second, calibration, alarm, century, watchdog, and square wave output information.
The device is packaged in a 44-pin, 330 mil SOIC with gold-plated contacts for direct connection to a separate SNAPHAT® housing containing the battery and crystal. This unique design allows the SNAPHAT battery package to be mounted after the surface mount process, preventing potential battery damage from high temperatures.
Key Specifications
| Parameter | Description | Value |
|---|---|---|
| Supply Voltage (VCC) | Operating voltage range | 3.0 to 3.6 V |
| Power-Fail Deselect Voltage (VPFD) | Write protect voltage range | 2.7 V ≤ VPFD ≤ 3.0 V |
| Operating Temperature | Ambient operating temperature range | 0 to 70°C |
| Package Type | Package and pin count | 44-pin SOIC |
| Battery and Crystal | Contained in SNAPHAT® housing | Yes |
| RoHS Compliance | Environmental compliance | Ecopack3, Lead-free second level interconnect |
| External RAM Capacity | Maximum external SRAM capacity | Up to 512 K x 8 |
| Watchdog Timer | Programmable watchdog timer functionality | Yes |
| Programmable Alarms | Programmable alarm output functionality | Yes |
| Square Wave Output | Square wave output functionality | Yes |
Key Features
- Integrated real-time clock, power-fail control circuit, battery, and crystal.
- Converts low power SRAM into NVRAMs.
- Battery low flag and year 2000 compliant.
- Programmable alarm output active in battery-backed mode.
- Microprocessor power-on reset valid even during battery backup mode.
- Choice of write protect voltages.
- SOIC package provides direct connection for a SNAPHAT® top containing the battery and crystal.
- RoHS compliant with lead-free second level interconnect.
- Watchdog timer with programmable alarm windows.
- Automatic backup and write protection for external SRAM.
Applications
The M48T201V-85MH1F is suitable for various applications requiring precise timekeeping and data retention during power failures. These include:
- Industrial control systems.
- Medical devices.
- Aerospace and defense systems.
- Automotive systems.
- Embedded systems requiring real-time clock functionality.
Q & A
- What is the primary function of the M48T201V-85MH1F?
The primary function is to provide a real-time clock, programmable alarms, a watchdog timer, and control for external low-power static RAM.
- What is the operating voltage range for the M48T201V-85MH1F?
The operating voltage range is 3.0 to 3.6 V.
- How does the SNAPHAT® housing protect the battery?
The SNAPHAT® housing is designed to be mounted after the surface mount process, preventing potential battery damage from high temperatures.
- Is the M48T201V-85MH1F RoHS compliant?
Yes, it is RoHS compliant with a lead-free second level interconnect.
- What is the maximum capacity of external SRAM supported by the M48T201V-85MH1F?
The device supports up to 512 K x 8 of external low-power static RAM.
- Does the M48T201V-85MH1F have a watchdog timer?
Yes, it includes a programmable watchdog timer.
- Can the alarm output be programmed?
Yes, the alarm output is programmable and active in battery-backed mode.
- How does the device handle power failures?
The device automatically switches to battery backup when the supply voltage falls below the battery backup switchover voltage, ensuring data and clock operation are maintained.
- Is the M48T201V-85MH1F year 2000 compliant?
Yes, it is year 2000 compliant.
- What is the purpose of the TIMEKEEPER® registers?
The TIMEKEEPER® registers store data such as year, month, date, day, hour, minute, second, calibration, alarm, century, watchdog, and square wave output information.
