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Renesas ISL12029IB27Z-T
- Part No.:
- ISL12029IB27Z-T
- Manufacturer:
- Renesas
- Category:
- Real Time Clocks
- Package:
- 14-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
ISL12029IB27Z-T.pdf
- Description:
- IC RTC CLK/CALENDAR I2C 14SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:4,663
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Product details
Overview
ISL12029IB27Z-T from Intersil is a low-power real-time clock/calendar IC with integrated 512×8-bit EEPROM, dual non-volatile alarms, CPU supervisor (POR, watchdog timer, low-voltage reset), and automatic battery backup switching. It operates from 2.7V to 5.5V main supply and retains timekeeping down to 1.8V on VBAT, uses an external 32.768kHz crystal, and delivers ±30ppm digital frequency adjustment via 64-position trim capacitor - deployed in utility meters and industrial control systems requiring long-term timestamp integrity.
For engineers reviewing the ISL12029IB27Z-T datasheet, ISL12029IB27Z-T pinout, ISL12029IB27Z-T application, or ISL12029IB27Z-T equivalent, key selection considerations include its 800nA battery current, I²C interface at 400kHz, 2.63V VRESET threshold, 14-lead SOIC package, and legacy power-control mode distinguishing it from ISL12029A variants.
Technical Context
The ISL12029IB27Z-T implements a fully autonomous RTC subsystem with separate BCD-encoded registers for seconds, minutes, hours, date, month, year (accurate through 2099), and day-of-week, plus automatic leap-year correction. Its oscillator compensation network integrates a digitally controlled 64-position trim capacitor and six discrete frequency adjustment settings (±30ppm) to calibrate crystal drift over temperature.
It features two independent non-volatile alarm registers supporting match-based triggering on second/minute/hour/day-of-week/date/month, repeat-mode periodic interrupts, and configurable IRQ/FOUT output (1Hz/4.096kHz/32.768kHz or open-drain interrupt). The CPU supervisor includes a 250ms power-on reset delay, three selectable watchdog timeout periods (225/750/1750ms), and five programmable VRESET thresholds (2.63V–4.64V).
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Main Supply Range | 2.7V to 5.5V - supports wide-input industrial and metering rails without external regulators |
| Battery Current (IBAT) | 800nA at VBAT = 1.8V - enables >10-year coin-cell operation in backup mode |
| I²C Speed | 400kHz - compatible with standard Fast-Mode I²C controllers without timing redesign |
| VRESET Threshold | 2.63V (fixed for ISL12029IB27Z-T) - triggers reliable system reset before brownout-induced MCU instability |
| EEPROM Capacity | 512 × 8 bits (32 pages × 16 bytes) - stores calibration data, configuration, and event logs with 50-year retention |
| Oscillator Accuracy | ±30ppm after digital trim - eliminates need for external load capacitors or manual crystal tuning |
| Package | 14-lead SOIC (M14.15) - industry-standard footprint compatible with automated assembly and thermal management up to +85°C |
Pinout & Package
ISL12029IB27Z-T is housed in a Pb-free, RoHS-compliant 14-lead SOIC package (JEDEC MS-012, pkg drawing M14.15), 8.65mm × 3.90mm × 1.75mm, with 1.27mm lead pitch. Thermal resistance θJA = 90°C/W enables stable operation in enclosed industrial enclosures.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| X1 | Oscillator input | Inverting amplifier input for 32.768kHz crystal - no external components required |
| X2 | Oscillator output | Crystal drive output - must not connect to external loads beyond crystal terminals |
| RESET | Open-drain reset output | Asserts active-low on VDD undervoltage or watchdog timeout; requires 5kΩ pull-up |
| GND | Ground reference | Primary return path for RTC, EEPROM, and supervisor circuits |
| VDD | Main power supply | Supplies all digital logic, I²C interface, and EEPROM programming circuitry |
| VBAT | Backup supply input | Enables continuous timekeeping during main power loss; valid down to 1.8V |
| IRQ/FOUT | Multi-function open-drain pin | Configurable as alarm interrupt or 1Hz/4.096kHz/32.768kHz clock output |
| SCL | I²C clock input | Always-active input buffer synchronizes all serial transfers; pull-up tied to VDD |
| SDA | I²C bidirectional data | Open-drain interface supports multi-master bus sharing and wire-OR logic |
Key Features
| Feature | Design Value |
|---|---|
| Integrated BlockLock™ EEPROM protection | 8 independent lock modes prevent accidental overwrite of critical calibration or security data |
| Dual non-volatile alarms | Each alarm retains settings across power cycles and supports periodic or one-shot triggering |
| Automatic battery switchover | Seamless transition from VDD to VBAT with no software intervention or timing gap |
| On-chip oscillator compensation | Digitally adjustable trim capacitor replaces external capacitors, reducing BOM count by ≥2 parts |
| Watchdog timer with 3 timeouts | 225ms / 750ms / 1750ms options enable flexible firmware supervision without external timers |
Applications
| Utility Metering | HVAC Control Systems |
|---|---|
Use Scenario: Time-stamping energy consumption data in smart electricity/water/gas meters with tamper-resistant logging. IC Role / Device Role / Timing Role: Primary RTC and non-volatile event logger; maintains accurate calendar and alarm-triggered data capture during grid outages. Use Value: 50-year EEPROM data retention and 800nA VBAT current ensure decade-long field deployment without battery replacement. |
Use Scenario: Scheduling fan speed, valve actuation, and temperature setpoints across daily/weekly cycles in commercial HVAC units. IC Role / Device Role / Timing Role: Calendar-aware scheduler with dual alarms driving timed control events and maintenance alerts. Use Value: Automatic leap-year and month-end correction prevents scheduling drift; 2.63V VRESET ensures clean MCU reset during AC line sags. |
| Network Infrastructure | Industrial Test Equipment |
Use Scenario: Timestamping packet statistics, firmware update logs, and SNMP trap events in routers, switches, and base stations. IC Role / Device Role / Timing Role: System timebase and secure configuration storage; provides synchronized timestamps across distributed nodes. Use Value: I²C 400kHz interface enables fast parameter reads/writes without blocking host CPU; 14-lead SOIC simplifies layout in dense PCBs. |
Use Scenario: Recording calibration cycles, test pass/fail timestamps, and environmental chamber logs in benchtop analyzers and fixtures. IC Role / Device Role / Timing Role: High-reliability timekeeper and non-volatile memory for audit-trail compliance (e.g., ISO/IEC 17025). Use Value: >2 million EEPROM write cycles support frequent logging; ±30ppm trimmed accuracy meets metrology-grade traceability requirements. |
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 |
|---|---|---|---|
| ISL12029AIB27Z-T | Standard Mode power control (BSW=0); VBAT trip point fixed at 2.2V vs. ISL12029IB27Z-T's Legacy Mode (BSW=1) and VDD < VBAT behavior | Required where VBAT > VDD is guaranteed; not interchangeable if VBAT may fall below VDD during backup | Select only if design mandates Standard Mode operation per "Power Control Operation" (p.14 datasheet) |
| DS3231SN#T&R | Integrated TCXO (±2ppm accuracy); higher cost; no built-in EEPROM; different I²C address (0x68) | Better accuracy-critical timing (e.g., telecom sync), but lacks EEPROM and alarm flexibility of ISL12029IB27Z-T | Choose when sub-ppm stability outweighs need for on-chip non-volatile storage and dual alarms |
Compared with ISL12029AIB27Z-T, the ISL12029IB27Z-T offers legacy power-switching behavior essential for VDD < VBAT designs, while DS3231SN#T&R trades EEPROM and alarm capability for superior oscillator stability - making ISL12029IB27Z-T optimal for cost-sensitive, feature-rich embedded metering where board space and component count matter.
Availability
ISL12029IB27Z-T is available at Aetrix Electronics and suitable for utility metering, HVAC control systems, and industrial test equipment requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.
Supply support for ISL12029IB27Z-T 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 Corporation (now part of Renesas Electronics) designs high-performance analog and mixed-signal ICs for industrial, communications, and computing markets, emphasizing reliability, low power, and integration.
The ISL12029 product line delivers highly integrated RTC+EEPROM+supervisor solutions targeting metering, infrastructure, and industrial control applications where time accuracy, data retention, and power resilience are critical.
FAQ
What is the VBAT operating voltage range for the ISL12029IB27Z-T?
The ISL12029IB27Z-T supports VBAT from 1.8V to 5.5V. Operation below 1.8V is not guaranteed - especially after a VDD power-down cycle - and may result in timekeeping failure or register corruption. At 1.8V, battery supply current is specified at 800nA, enabling multi-year operation with common lithium coin cells. The device remains fully functional in calendar and RTC modes down to this minimum VBAT.
Does the ISL12029IB27Z-T support I²C communication during battery backup mode?
Yes, the ISL12029IB27Z-T supports I²C communication during battery backup mode, but only if the I²C-enable bit (bit 7 of the Status Register) is explicitly set before VDD loss. By default, the I²C interface is disabled in battery mode to conserve current. Enabling it allows host processors to read time, alarms, or EEPROM data even when main power is absent - a key capability for fault logging and diagnostics in unattended systems.
How does the ISL12029IB27Z-T handle leap years and month-end date rollover?
The ISL12029IB27Z-T implements full calendar logic including automatic leap-year correction (years divisible by 4), variable month lengths (28–31 days), and day-of-week tracking. It correctly advances from February 28 to March 1 in non-leap years and from February 29 to March 1 in leap years. This behavior is hardware-automated and requires no firmware intervention, ensuring accurate date stamping across decades without software date-handling routines.
What is the function of the IRQ/FOUT pin on the ISL12029IB27Z-T?
The IRQ/FOUT pin on the ISL12029IB27Z-T is a dual-function open-drain output configurable via the control/status register. In interrupt mode, it asserts active-low on alarm match or watchdog timeout. In frequency output mode, it delivers user-selectable clocks: 1Hz, 4.096kHz, or 32.768kHz - derived directly from the crystal oscillator. A pull-up resistor (recommended 5kΩ–10kΩ) is required; improper values may degrade oscillator stability or waveform fidelity.
Can the ISL12029IB27Z-T be used as a direct replacement for the ISL12029IB27AZ-T?
No - the ISL12029IB27Z-T and ISL12029IB27AZ-T are not direct replacements due to differing VRESET thresholds: 2.63V vs. 2.92V. This difference affects system reset behavior during brownout conditions. While both share identical pinout, package, and core functionality, substituting them without validating reset timing margins risks unreliable power-fail recovery. Always verify VRESET compatibility against the host system's supply rail tolerances before interchange.
ISL12029IB27Z-T Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Renesas
- Series:
- -
- Package/Case:
- 14-SOIC (0.154", 3.90mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Programmable:
- Not Verified
- Type:
- Clock/Calendar
- Features:
- Alarm, Leap Year, Supervisor, Watchdog Timer
- 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 ~ 5.5V
- Operating Temperature:
- -40°C ~ 85°C
- Mounting Type:
- Surface Mount
- Grade:
- -
- Qualification:
- -
- Supplier Device Package:
- 14-SOIC
ISL12029IB27Z-T FAQ
1.How can I place an order for ISL12029IB27Z-T through Aetrix?
Please submit a Request for Quotation (RFQ) for ISL12029IB27Z-T 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 ISL12029IB27Z-T reliable?
The price and inventory of ISL12029IB27Z-T are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for ISL12029IB27Z-T is usually 5 days.
3.What payment methods are accepted for ISL12029IB27Z-T?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for ISL12029IB27Z-T transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for ISL12029IB27Z-T?
ISL12029IB27Z-T orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your ISL12029IB27Z-T 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 ISL12029IB27Z-T?
For technical support, including ISL12029IB27Z-T datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your ISL12029IB27Z-T requirements.
6.How does Aetrix verify that ISL12029IB27Z-T is sourced from the original manufacturer or authorized distributors?
All ISL12029IB27Z-T 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 ISL12029IB27Z-T meets industry standards.
7.What is the process for return or replacement of ISL12029IB27Z-T?
All ISL12029IB27Z-T units undergo pre-shipment inspection (PSI). If there is an issue with ISL12029IB27Z-T, 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 ISL12029IB27Z-T part is unused and in its original packaging.
Return procedure for ISL12029IB27Z-T:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
ISL12029IB27Z-T Tags
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MCP7940N-I/SN
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PCF85063ATL/1,118
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PCF85063AT/AY
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PCF85063TP/1Z
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