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Microchip Technology 93LC66T/SN
- Part No.:
- 93LC66T/SN
- Manufacturer:
- Microchip Technology
- Category:
- Memory
- Package:
- 8-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
93LC66T/SN.pdf
- Description:
- IC EEPROM 4KBIT MICROWIRE 8SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:2,342
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Product details
Overview
93LC66T/SN from Microchip Technology Inc. is a 4K-bit (512 × 8 or 256 × 16) low-voltage serial EEPROM with Microwire™ interface, designed for nonvolatile data storage in space-constrained embedded systems. It operates from 2.5V to 5.5V, draws only 100 µA typical active read current at 2.5V, and supports industrial temperature range (–40°C to +85°C). Its ORG-pin-selectable memory organization enables flexible byte/word addressing in microcontroller peripherals, power management units, and sensor calibration modules.
For engineers reviewing the 93LC66T/SN datasheet, 93LC66T/SN pinout, 93LC66T/SN application, or 93LC66T/SN equivalent, key selection criteria include its 3-wire serial interface timing compliance (FCLK ≤ 2 MHz at VCC < 4.5V), self-timed 4 ms per-word write/erase cycles, 1 million endurance cycles, and SOIC-8 package compatibility with legacy PCB footprints requiring minimal layout revision.
Technical Context
The 93LC66T/SN implements a synchronous 3-wire Microwire-compatible protocol with CS, CLK, and bidirectional DI/DO lines. Instruction execution requires a Start bit followed by opcode, address, and optional data bits - all clocked on CLK rising edges. Memory organization (x8 or x16) is determined solely by the logic level applied to the ORG pin during power-up.
During erase/write operations, the DO pin functions as a Ready/Busy status indicator: low = programming in progress, high = operation complete. The device includes power-on/off data protection circuitry that inhibits programming below 1.4V, and requires explicit EWEN/EWDS commands to gate erase/write access - preventing accidental writes during brown-out or noise events.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Memory size | 4 Kbit (512 × 8 or 256 × 16 organization selectable via ORG pin) |
| Supply voltage | 2.5V to 5.5V - enables direct interface with 2.5V/3.3V/5V microcontrollers without level-shifting |
| Active read current | 100 µA at 2.5V - supports ultra-low-power battery-backed applications like smart meters and IoT sensors |
| Standby current | 3 µA at 2.5V - ensures minimal quiescent drain during system sleep modes |
| Endurance | 1,000,000 erase/write cycles - guarantees long-term reliability in firmware parameter logging and calibration storage |
| Data retention | >200 years at 25°C - meets industrial requirements for unattended field-deployed equipment |
| Write cycle time | 4 ms per word typical - enables deterministic timing budgeting for real-time control loops |
Pinout & Package
93LC66T/SN is housed in an 8-lead narrow SOIC (SN) package per JEDEC MS-012, with dimensions 4.90 mm × 3.91 mm × 1.55 mm (L × W × A). Pin 1 is marked by a beveled corner or dot; the package is lead-free and RoHS-compliant.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| CS (Pin 1) | Chip Select | Active-high enable signal; must be held low ≥250 ns between instructions to reset internal state |
| CLK (Pin 2) | Serial Clock | Synchronizes all data transfers; rising edge clocks in opcode/address/data; stoppable mid-sequence |
| DI (Pin 3) | Data Input | Receives Start bit, opcode, address, and write data; shares net with DO only if bus conflict mitigation is implemented |
| DO (Pin 4) | Data Output / Status | Outputs read data or Ready/Busy status (low = busy); high-Z when inactive; requires pull-up for reliable status polling |
| VSS (Pin 5) | Ground | Reference return path for all digital and analog functions; must be low-impedance connection |
| ORG (Pin 6) | Organization Select | High = x16 mode (256 words); low = x8 mode (512 bytes); floating allowed only at ≤1 MHz clock rate |
| NU (Pin 7) | No Connect | Internally unconnected; must remain unconnected on PCB to avoid parasitic coupling or ESD paths |
| VCC (Pin 8) | Power Supply | Accepts 2.5V–5.5V; internal voltage monitor blocks programming below 1.4V for power-fail safety |
Key Features
| Feature | Design Value |
|---|---|
| ORG-pin memory configuration | Enables runtime selection between 512-byte and 256-word layouts without firmware change or BOM update |
| Self-timed erase/write cycles | Eliminates need for external timing control or watchdog timeout logic - simplifies host MCU firmware |
| Device status signaling | DO pin provides real-time Ready/Busy feedback during programming, enabling efficient polling instead of fixed delays |
| Power-on/off data protection | Hardware-enforced write inhibition below 1.4V prevents corruption during brown-out or hot-plug events |
| Sequential read function | Allows continuous burst reads across multiple addresses with single CS assertion - reduces transaction overhead |
Applications
| Industrial Sensor Calibration | Consumer Remote Control Memory |
|---|---|
|
Use Scenario: Storing factory-trimmed offset/gain coefficients for analog sensor front-ends in programmable logic controllers. IC Role / Device Role / Timing Role: Nonvolatile parameter storage accessed during boot-up; x16 mode used for compact coefficient pairs. Use Value: Enables one-time calibration at manufacturing with guaranteed 200-year retention - eliminates recalibration service visits. |
Use Scenario: Retaining user-configured channel presets, volume levels, and backlight brightness settings in IR remote handsets. IC Role / Device Role / Timing Role: Low-power configuration store updated infrequently; x8 mode matches byte-oriented MCU register maps. Use Value: 3 µA standby current extends coin-cell battery life beyond 5 years while supporting 1M+ button-press cycles. |
| Medical Device Configuration | Automotive Body Control Module |
|
Use Scenario: Saving patient-specific therapy parameters and usage logs in portable infusion pumps. IC Role / Device Role / Timing Role: Secure, tamper-resistant data archive; EWEN/EWDS commands enforce intentional write authorization. Use Value: 1M endurance cycles support full lifetime logging at 100 records/day for >27 years - exceeds FDA 10-year device lifecycle requirement. |
Use Scenario: Storing door lock/unlock patterns, mirror position memories, and seat adjustment profiles in vehicle BCMs. IC Role / Device Role / Timing Role: Robust EEPROM interfaced directly to 5V automotive MCUs; SOIC-8 footprint fits tight under-dash space constraints. Use Value: Industrial temperature rating (–40°C to +85°C) and 5.5V tolerance ensure reliable operation across engine bay thermal transients. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar serial EEPROM applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 93LC66C-I/SN | Pin-compatible successor with enhanced ESD rating (≥6 kV HBM), improved AC timing margins, and extended 10-year data retention guarantee. | Preferred for new designs requiring long-term supply assurance and higher robustness in noisy automotive/industrial environments. | Select 93LC66C-I/SN when designing new products; it maintains identical pinout, instruction set, and memory map. |
| AT25040B-MAU-10 | 4-Kbit SPI EEPROM (not Microwire); requires different clock polarity/phase setup and lacks ORG-pin organization flexibility. | Suitable where existing SPI master infrastructure exists but incompatible with legacy Microwire-based firmware stacks. | Choose AT25040B-MAU-10 only if migrating from SPI-based systems - firmware and timing logic must be rewritten. |
Compared with 93LC66T/SN, the 93LC66C-I/SN offers drop-in reliability upgrades without layout or software changes, while the AT25040B-MAU-10 demands full interface redesign but provides broader SPI ecosystem support and higher production volumes.
Availability
93LC66T/SN is available at Aetrix Electronics and suitable for industrial sensor calibration, medical device configuration, automotive body control modules, and consumer remote control memory requiring stable component supply across multi-year production cycles.
Supply support for 93LC66T/SN 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
Microchip Technology Inc. is a leading provider of microcontroller, mixed-signal, analog, and Flash-IP solutions, headquartered in Chandler, Arizona, with global design and sales operations.
The 93LC66T/SN belongs to Microchip's legacy 93LCxx Microwire EEPROM family, engineered for cost-sensitive, low-power embedded systems needing simple, proven nonvolatile storage with minimal MCU resource overhead.
FAQ
What is the memory organization of 93LC66T/SN and how is it selected?
The 93LC66T/SN supports dual memory configurations: 512 × 8-bit (x8) or 256 × 16-bit (x16), selected exclusively by the logic level applied to the ORG pin at power-up. When ORG is tied to VCC, x16 mode activates; when grounded, x8 mode engages. This hardware-selectable organization allows the same 93LC66T/SN part to serve both byte-addressed and word-addressed MCU architectures without firmware modification.
Does 93LC66T/SN require external timing components for write operations?
No, the 93LC66T/SN performs fully self-timed erase and write cycles - including automatic pre-erase (ERAL) before WRAL - with no external capacitors or clocks needed. Each write or erase operation completes in 4 ms per word (typical), and the DO pin signals readiness via Ready/Busy status, eliminating reliance on fixed software delays and improving system determinism.
How does 93LC66T/SN protect against accidental writes during power transitions?
The 93LC66T/SN integrates hardware-level power-fail protection: programming modes are inhibited until VCC rises above 1.4V at power-on, and disabled again once VCC falls below 1.4V during power-down. Additionally, all erase/write operations require explicit EWEN (Erase/Write Enable) command execution - the device powers up in EWDS (Erase/Write Disable) state, preventing unintended modifications.
Can 93LC66T/SN be used with modern 3.3V or 1.8V microcontrollers?
Yes, the 93LC66T/SN operates over a wide VCC range of 2.5V to 5.5V, making it compatible with 3.3V MCUs without level shifters. While its absolute minimum supply is 2.5V, it is not rated for 1.8V operation - using it below 2.5V may result in unreliable communication or incomplete writes. For true 1.8V systems, Microchip's newer 93AAxx or 25AAxx families are recommended alternatives.
What is the significance of the "T" suffix in 93LC66T/SN?
The "T" in 93LC66T/SN denotes tape-and-reel packaging - specifically, the device is supplied in industry-standard 13-inch reels optimized for automated SMT placement. This format ensures consistent feeding accuracy, minimizes handling damage, and supports high-volume manufacturing. The "/SN" suffix confirms the narrow SOIC-8 (150-mil) package variant, distinct from PDIP or rotated SOIC versions.
93LC66T/SN Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- 8-SOIC (0.154", 3.90mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Programmable:
- Verified
- Memory Type:
- Non-Volatile
- Memory Format:
- EEPROM
- Technology:
- EEPROM
- Memory Size:
- 4Kbit
- Memory Organization:
- 512 x 8, 256 x 16
- Memory Interface:
- Microwire
- Clock Frequency:
- 2 MHz
- Write Cycle Time - Word, Page:
- 10ms
- Access Time:
- -
- Voltage - Supply:
- 2.5V ~ 5.5V
- Operating Temperature:
- 0°C ~ 70°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 8-SOIC
93LC66T/SN FAQ
1.How can I place an order for 93LC66T/SN through Aetrix?
Please submit a Request for Quotation (RFQ) for 93LC66T/SN 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 93LC66T/SN reliable?
The price and inventory of 93LC66T/SN are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 93LC66T/SN is usually 5 days.
3.What payment methods are accepted for 93LC66T/SN?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 93LC66T/SN transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 93LC66T/SN?
93LC66T/SN orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 93LC66T/SN 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 93LC66T/SN?
For technical support, including 93LC66T/SN datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 93LC66T/SN requirements.
6.How does Aetrix verify that 93LC66T/SN is sourced from the original manufacturer or authorized distributors?
All 93LC66T/SN 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 93LC66T/SN meets industry standards.
7.What is the process for return or replacement of 93LC66T/SN?
All 93LC66T/SN units undergo pre-shipment inspection (PSI). If there is an issue with 93LC66T/SN, 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 93LC66T/SN part is unused and in its original packaging.
Return procedure for 93LC66T/SN:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
93LC66T/SN Tags
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M24C02-WMN6TP
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AT24C02C-XHM-T
Microchip Technology
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AT21CS01-STUM10-T
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AT24C02C-SSHM-T
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24LC01BT-I/OT
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M24C02-FMC6TG
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AT24CS02-SSHM-T
Microchip Technology
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93LC46BT-I/OT
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AT24C04C-SSHM-T
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24LC01BT-I/SN
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24AA02UIDT-I/OT
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AT24C08C-STUM-T
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