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Renesas X1226S8IZ
- Part No.:
- X1226S8IZ
- Manufacturer:
- Renesas
- Category:
- Real Time Clocks
- Package:
- 8-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
X1226S8IZ.pdf
- Description:
- IC RTC CLK/CALENDAR I2C 8SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:2,028
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Product details
Overview
X1226S8IZ from Intersil is a real-time clock/calendar IC with integrated 512 × 8-bit EEPROM, dual non-volatile alarms, on-chip oscillator compensation, and 2-wire (I²C-compatible) interface. It operates from 2.7–5.5 V, draws 1.25 µA typical operating current, and maintains timekeeping down to 1.8 V in standby mode using VBACK backup supply.
For engineers reviewing the X1226S8IZ datasheet, X1226S8IZ pinout, X1226S8IZ application, or X1226S8IZ equivalent, this device supports precise timekeeping with ±30 ppm digital frequency adjustment, programmable 1 Hz/4096 Hz/32.768 kHz output, and BlockLock™ EEPROM protection - critical for utility metering, industrial control, and network infrastructure timing integrity.
Technical Context
The X1226S8IZ integrates a 32.768 kHz crystal oscillator with fully on-die analog (6-bit ATR) and digital (3-bit DTR) trim circuitry, enabling ±30 ppm fine-tuning and up to +146 ppm total compensation range. Its RTC registers store BCD-encoded time/date values with automatic leap-year correction through 2099.
Alarm logic supports two independent, match-based alarms with repeat mode and interrupt/polling capability via PHZ/IRQ pin; EEPROM features 64-byte page writes, 100,000 write cycles per byte, and eight block-lock protection modes. Power management switches seamlessly between VCC and VBACK without external circuitry.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| RTC Accuracy | ±30 ppm digitally adjustable; enables <1 min/month drift with proper crystal selection and trimming |
| Interface | I²C-compatible 2-wire at 400 kHz; open-drain SDA/SCL with slope-controlled fall time |
| EEPROM Size | 512 × 8 bits (4 Kb); supports single-byte and 64-byte page writes with 100,000 endurance cycles |
| Alarm Capability | Dual non-volatile alarms; match on second/minute/hour/day-of-week/date/month with repeat mode |
| Frequency Output | SW-selectable: 1 Hz, 4096 Hz, or 32.768 kHz on PHZ/IRQ pin; replaces external divider circuits |
| Backup Supply | VBACK input supports battery/supercap; RTC remains functional down to 1.8 V during main power loss |
| Operating Voltage | 2.7–5.5 V (VCC); full functionality across industrial temperature range (−40°C to +85°C) |
| Package | 8-lead SOIC (150 mil), Pb-free plus anneal (RoHS compliant); MDP0027 footprint |
Pinout & Package
8-lead SOIC (150 mil) package per MDP0027 drawing; RoHS-compliant Pb-free plus anneal finish.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| X1 | Oscillator Input | Inverting amplifier input for external 32.768 kHz crystal; requires short trace and ground plane for stability |
| X2 | Oscillator Output | Inverting amplifier output; completes crystal oscillator loop with internal compensation circuitry |
| PHZ/IRQ | Programmable Output | Open-drain pin configurable as 1 Hz/4096 Hz/32.768 kHz frequency source or active-low alarm interrupt |
| VSS | Ground Reference | Primary digital ground; must be connected to system ground plane with low-impedance path |
| SDA | Serial Data I/O | Bidirectional open-drain data line; requires external pull-up; supports 400 kHz I²C transfers |
| SCL | Serial Clock Input | Master-generated clock input; always-active buffer enables reliable synchronization |
| VBACK | Backup Supply Input | Provides power to RTC during VCC failure; accepts battery, supercap, or grounded if unused |
| VCC | Main Supply Input | Primary power rail (2.7–5.5 V); powers all functions except RTC in standby (down to 1.8 V) |
Key Features
| Feature | Design Value |
|---|---|
| On-chip oscillator compensation | 64-position digital trim capacitor + 6-step ±30 ppm digital adjustment + 6-bit analog capacitance tuning (3.25–18.75 pF) |
| Dual non-volatile alarms | Two independent alarms with maskable fields (second to month), repeat mode, and status polling/interrupt output |
| BlockLock™ EEPROM protection | Eight programmable lock modes protect 1/8 to full 4 Kb array; prevents accidental overwrites of critical configuration data |
| Low-power RTC operation | 1.25 µA typical operating current; retains time/date with VBACK down to 1.8 V; 100-year data retention |
| Industrial temperature support | Rated for −40°C to +85°C operation; validated across full range for utility meters, HVAC, and telecom infrastructure |
| Pb-free plus anneal packaging | Matte tin termination compatible with SnPb and Pb-free reflow; MSL rating meets IPC/JEDEC J-STD-020 requirements |
Applications
| Utility Metering | HVAC Control Systems |
|---|---|
Use Scenario: Time-stamping energy consumption data in smart electricity/water/gas meters for billing and load profiling. IC Role / Device Role / Timing Role: Primary RTC providing accurate, tamper-resistant time/date stamps synchronized to utility grid time standards. Use Value: Enables compliance with ANSI C12.1 and IEC 62056 standards via 100-year data retention, ±30 ppm accuracy, and VBACK-powered timekeeping during mains outage. |
Use Scenario: Scheduling fan speeds, compressor cycles, and setpoint adjustments in commercial HVAC controllers. IC Role / Device Role / Timing Role: Real-time calendar engine managing weekly/daily schedules and seasonal daylight savings transitions. Use Value: Eliminates need for external crystal trim components and backup power circuitry while supporting −40°C to +85°C ambient operation. |
| Network Infrastructure | Industrial Automation |
Use Scenario: Timestamping SNMP traps, syslog entries, and firmware update logs in routers, switches, and base stations. IC Role / Device Role / Timing Role: System-level timekeeper ensuring consistent event sequencing across distributed network nodes. Use Value: Provides deterministic 1 Hz pulse output for watchdog synchronization and supports I²C-bus sharing with other peripherals at 400 kHz. |
Use Scenario: Coordinating PLC scan cycles, motion controller trajectories, and HMI session timeouts in factory-floor equipment. IC Role / Device Role / Timing Role: High-reliability RTC maintaining uptime during brownouts and enabling scheduled maintenance alerts. Use Value: Delivers 100,000 EEPROM write cycles for logging operational events and leverages BlockLock™ to safeguard calibration constants. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar real-time clock/calendar applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| DS1307+T&R | Lacks on-chip oscillator compensation; no digital/analog trim; only 1 alarm; no BlockLock™ EEPROM protection | Lower accuracy (±2 ppm crystal-dependent); limited alarm flexibility; less secure EEPROM for configuration storage | Select when cost sensitivity outweighs precision timing needs and backup power integrity is secondary |
| PCF8583P | No integrated EEPROM; separate 256-byte RAM; no VBACK switching circuitry; no programmable frequency output | Requires external backup power management; no 1 Hz/4096 Hz output for system clocks; no EEPROM-based parameter storage | Choose for legacy I²C systems where minimal feature set suffices and external memory is already present |
Compared with DS1307+T&R and PCF8583P, the X1226S8IZ delivers superior timing autonomy via on-die compensation, dual alarms with repeat mode, and hardware-enforced EEPROM security - making it optimal for applications requiring long-term accuracy, robust event scheduling, and tamper-resistant configuration storage.
Availability
X1226S8IZ is available at Aetrix Electronics and suitable for utility metering, HVAC control systems, and network infrastructure requiring stable component supply, industrial temperature resilience, and long-term timing accuracy.
Supply support for X1226S8IZ 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
Intersil (now part of Renesas Electronics) designs high-performance analog and mixed-signal ICs for industrial, communications, and computing markets.
The X1226S8IZ belongs to Intersil's RTC family engineered for precision timekeeping in resource-constrained, battery-backed systems - emphasizing low power, integrated compensation, and EEPROM-based configuration persistence.
FAQ
What is the operating voltage range for the X1226S8IZ?
The X1226S8IZ operates from 2.7 V to 5.5 V on VCC for full functionality. During main power loss, its RTC continues running down to 1.8 V using the VBACK supply - a key design feature enabling uninterrupted timekeeping in utility meters and industrial controllers. This dual-voltage capability is verified in the FN8098 datasheet Section "POWER CONTROL OPERATION".
Does the X1226S8IZ require an external crystal?
Yes, the X1226S8IZ requires an external 32.768 kHz quartz crystal connected between X1 and X2 pins. The recommended part is Citizen CFS206-32.768KDZF. Unlike some newer RTCs, it does not include a built-in resonator - but compensates with on-die analog and digital trim circuitry to optimize crystal accuracy without discrete capacitors.
How many alarms does the X1226S8IZ support, and what trigger modes are available?
The X1226S8IZ supports two independent, non-volatile alarms (Alarm 0 and Alarm 1). Each can be configured to match on second, minute, hour, day-of-week, date, or month - enabling use cases like daily 9:00 AM notifications or monthly maintenance alerts. Both alarms support repeat mode (periodic interrupts) and can be polled via status register or signaled via the PHZ/IRQ pin.
What EEPROM protection features does the X1226S8IZ offer?
The X1226S8IZ implements BlockLock™ protection with eight programmable lock modes controlled by BP2–BP0 bits. These modes allow selective write-protection of memory blocks - from the first 128 bytes up to the entire 4 Kb array. This ensures critical calibration data or firmware parameters remain immune to accidental overwrites during field updates or runtime operations.
Is the X1226S8IZ pin-compatible with other members of the X1226 family?
Yes, the X1226S8IZ shares identical 8-lead SOIC pinout and electrical interface with all X1226 variants (e.g., X1226S8I, X1226S8Z). Differences are limited to temperature grade (−40°C to +85°C), Pb-free anneal process, and marking - not pin function or layout. This allows direct substitution in existing designs without PCB changes when upgrading to extended temperature or RoHS-compliant versions.
X1226S8IZ Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Renesas
- Series:
- -
- Package/Case:
- 8-SOIC (0.154", 3.90mm Width)
- Packaging:
- Tube
- Product Status:
- Obsolete
- Programmable:
- Not Verified
- Type:
- Clock/Calendar
- Features:
- Alarm, Leap Year
- Memory Size:
- -
- Time Format:
- HH:MM:SS (12/24 hr)
- Date Format:
- YY-MM-DD-dd
- Interface:
- I2C, 2-Wire Serial
- Voltage - Supply:
- 2.7V ~ 5.5V
- Voltage - Supply, Battery:
- 1.8V ~ 5.5V
- Current - Timekeeping (Max):
- 10µA ~ 20µA @ 2.7V ~ 5V
- Operating Temperature:
- -40°C ~ 85°C
- Mounting Type:
- Surface Mount
- Grade:
- -
- Qualification:
- -
- Supplier Device Package:
- 8-SOIC
X1226S8IZ FAQ
1.How can I place an order for X1226S8IZ through Aetrix?
Please submit a Request for Quotation (RFQ) for X1226S8IZ 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 X1226S8IZ reliable?
The price and inventory of X1226S8IZ are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for X1226S8IZ is usually 5 days.
3.What payment methods are accepted for X1226S8IZ?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for X1226S8IZ transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for X1226S8IZ?
X1226S8IZ orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your X1226S8IZ 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 X1226S8IZ?
For technical support, including X1226S8IZ datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your X1226S8IZ requirements.
6.How does Aetrix verify that X1226S8IZ is sourced from the original manufacturer or authorized distributors?
All X1226S8IZ 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 X1226S8IZ meets industry standards.
7.What is the process for return or replacement of X1226S8IZ?
All X1226S8IZ units undergo pre-shipment inspection (PSI). If there is an issue with X1226S8IZ, 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 X1226S8IZ part is unused and in its original packaging.
Return procedure for X1226S8IZ:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
X1226S8IZ Tags
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MCP7940N-I/SN
Microchip Technology
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MCP7940MT-I/MNY
Microchip Technology
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PCF85063ATL/1,118
NXP USA Inc.
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MCP7940NT-I/SN
Microchip Technology
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MCP7940NT-I/MS
Microchip Technology
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MCP7940N-I/MS
Microchip Technology
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PCF85063AT/AY
NXP USA Inc.
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PCF85063TP/1Z
NXP Semiconductors
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PCF85063ATT/AJ
NXP USA Inc.
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MCP7940NT-E/SN
Microchip Technology
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MCP7940NT-I/MNY
Microchip Technology
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MCP79400T-I/SN
Microchip Technology
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