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Microchip Technology 93LC66CT-E/MS
- Part No.:
- 93LC66CT-E/MS
- Manufacturer:
- Microchip Technology
- Category:
- Memory
- Package:
- 8-TSSOP, 8-MSOP (0.118", 3.00mm Width)
- Datasheet:
-
93LC66CT-E/MS.pdf
- Description:
- IC EEPROM 4KBIT MICROWIRE 8MSOP
- Quantity:
- Payment:
- Shipping:
Inventory:2,785
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Product details
Overview
93LC66CT-E/MS from Microchip Technology Inc. is a 4 Kbit low-voltage serial EEPROM with Microwire-compatible 3-wire interface, 256 × 16-bit organization (dedicated x16), and industrial-temperature operation (–40°C to +85°C). It features self-timed erase/write cycles, automatic ERAL before WRAL, power-on/off data protection, and Ready/Busy status signaling via DO pin - used in embedded system configuration storage and calibration data retention.
For engineers reviewing the 93LC66CT-E/MS datasheet, 93LC66CT-E/MS pinout, 93LC66CT-E/MS application, or 93LC66CT-E/MS equivalent, key selection considerations include VCC range (2.5–5.5 V), 16-bit word access, MSOP-8 package compatibility, endurance (1 million cycles), and automotive-grade temperature support (E-temp version available separately).
Technical Context
The 93LC66CT-E/MS implements a synchronous serial Microwire interface with CS, CLK, DI, and DO signals, requiring a Start bit followed by opcode, address, and data. Its fixed 16-bit organization eliminates ORG pin dependency - unlike 'C' variants - simplifying hardware design for systems needing consistent 16-bit word access.
Internal logic includes auto-erase-before-write, automatic ERAL prior to WRAL, and EWEN/EWDS command-based write protection. The DO pin serves dual function: serial data output during READ and Ready/Busy status indicator during programming - active high when ready, low during erase/write, and High-Z when CS is low.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Memory Size | 4 Kbit (256 × 16-bit) - provides compact nonvolatile storage for firmware parameters or device calibration tables. |
| VCC Range | 2.5 V to 5.5 V - supports direct interfacing with 3.3 V and 5 V microcontrollers without level-shifting. |
| Endurance | 1,000,000 erase/write cycles - ensures long-term reliability in field-updatable systems with frequent configuration changes. |
| Data Retention | 200 years at 25°C - guarantees data integrity over product lifetime without refresh. |
| Write Cycle Time | 6 ms typical (TWC) - defines minimum time between successive WRITE/ERAL/WRAL commands; impacts real-time update latency. |
| Interface | Microwire-compatible 3-wire serial (CS/CLK/DI/DO) - requires only four GPIOs and no external components for basic operation. |
| Temp Range | –40°C to +85°C (Industrial grade) - validated for use in industrial control, metering, and consumer electronics environments. |
Pinout & Package
8-pin MSOP (Micro Small Outline Package), 3.0 mm × 3.0 mm body, 0.65 mm pitch, exposed pad optional (VSS or floating), Pb-free Matte Tin finish.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| CS | Chip Select | Active-high enable; must be held low ≥250 ns between instructions; deselects device into standby mode. |
| CLK | Serial Clock | Synchronizes all data transfers; rising edge clocks in opcode/address/data; stoppable mid-sequence. |
| DI | Data Input | Receives Start bit, instruction opcodes, addresses, and write data; tied to VSS or VCC for EWDS/EWEN. |
| DO | Data Output / Status | Outputs read data on rising CLK edge; indicates Ready (high) or Busy (low) during programming when CS is reasserted. |
| VSS | Ground | Reference for all digital and analog circuitry; connected to exposed pad in DFN/TDFN variants. |
| NC | No Internal Connection | Pin 7 in MSOP - unconnected; must not be biased or loaded. |
| VCC | Power Supply | Supplies core logic and memory array; internal POR triggers below 1.5 V (93LC series). |
| ORG | Organization Select | Not present on 93LC66A/B - this part is fixed x16; ORG pin omitted or NC in A/B variants per datasheet. |
Key Features
| Feature | Design Value |
|---|---|
| Self-timed Erase/Write | Eliminates need for external timing control - internal state machine manages auto-erase and programming, reducing host MCU overhead. |
| Automatic ERAL before WRAL | Ensures full array erase before bulk write, preventing partial-data corruption without software intervention. |
| Power-On/Off Data Protection | Hardware-level VCC monitoring disables writes below 1.5 V, preventing inadvertent corruption during brown-out or power ramp. |
| Ready/Busy Status via DO | Enables polling-based flow control - host reads DO after CS high pulse to determine completion without fixed delays. |
| Sequential Read Mode | Allows continuous read across multiple addresses with single CS assertion, improving throughput for block data retrieval. |
Applications
| Industrial Sensor Calibration | Consumer Appliance Configuration |
|---|---|
Use Scenario: Storing factory-trimmed sensor offset/gain coefficients and temperature compensation tables in pressure or humidity sensors. IC Role / Device Role / Timing Role: Nonvolatile configuration register accessed during power-up initialization and field recalibration routines. Use Value: Enables accurate sensor output without external NVM or MCU flash wear - leverages 200-year retention and 1M-cycle endurance. | Use Scenario: Saving user preferences (e.g., cooking modes, timer settings, display brightness) in microwave ovens and washing machines. IC Role / Device Role / Timing Role: Standalone serial EEPROM interfaced directly to 8-bit MCU GPIOs for persistent parameter storage. Use Value: Provides reliable, low-power, pin-efficient storage independent of MCU flash lifecycle limitations. |
| Medical Device Settings Backup | Automotive Body Control Module |
Use Scenario: Retaining therapy parameters, alarm thresholds, and usage logs in portable infusion pumps and blood glucose meters. IC Role / Device Role / Timing Role: Safety-critical configuration store with verified data integrity; accessed during boot and runtime updates. Use Value: Meets IEC 62304 requirements for configurable medical devices via deterministic write timing and hardware write protection (EWDS). | Use Scenario: Storing door lock configuration, mirror position presets, and lighting profiles in vehicle BCMs. IC Role / Device Role / Timing Role: Dedicated 16-bit NVM for multi-byte parameter sets; accessed via low-speed serial bus under ECU control. Use Value: Supports automotive-grade reliability with industrial temp range and 2.5–5.5 V operation compatible with 12 V system regulators. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar serial EEPROM applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 93LC66B-I/MS | Same 256×16-bit organization, identical MSOP-8 package, but Industrial grade (–40°C to +85°C) without E-temp marking; no 'T' suffix. | Valid for same industrial applications but lacks explicit traceability code 'T' and E-temp qualification; suitable where extended temp not required. | Select 93LC66B-I/MS if E-temp certification and production traceability (T-marking) are unnecessary. |
| AT25040B-MAHL-T | 4 Kbit SPI EEPROM (256×16), SOIC-8, 1.8–5.5 V, 20 MHz SPI interface - faster clock, different protocol, no Ready/Busy pin. | Requires SPI master instead of Microwire; no hardware status polling - relies on WIP flag read or fixed delay. | Choose AT25040B-MAHL-T only when migrating to SPI infrastructure and accepting software-managed timing. |
Compared with 93LC66B-I/MS, the 93LC66CT-E/MS adds production traceability (T-marking) and E-temp qualification; versus AT25040B-MAHL-T, it retains Microwire compatibility and hardware Ready/Busy signaling - critical for resource-constrained or legacy designs.
Availability
93LC66CT-E/MS is available at Aetrix Electronics and suitable for industrial sensor calibration, consumer appliance configuration, medical device settings backup, and automotive body control module applications requiring stable component supply, long-term data retention, and RoHS-compliant packaging.
Supply support for 93LC66CT-E/MS 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, serving industrial, automotive, and consumer markets globally.
The 93LC66CT-E/MS belongs to Microchip's legacy 93XX serial EEPROM family, designed specifically for cost-sensitive, low-power embedded systems requiring simple, robust, and pin-efficient nonvolatile memory with hardware write protection and status feedback.
FAQ
What is the memory organization of the 93LC66CT-E/MS?
The 93LC66CT-E/MS has a fixed 256 × 16-bit (4 Kbit) organization. Unlike 'C' variants, it does not use the ORG pin - it is a dedicated 'B'-type device, meaning word size is permanently set to 16 bits. This eliminates external logic for configuration and simplifies PCB layout for systems requiring consistent 16-bit access. The 93LC66CT-E/MS delivers deterministic addressing and data framing without runtime reconfiguration.
Does the 93LC66CT-E/MS support hardware write protection?
Yes, the 93LC66CT-E/MS supports hardware write protection via the EWEN (Erase/Write Enable) and EWDS (Erase/Write Disable) instructions. It powers up in EWDS mode, blocking all erase/write operations until EWEN is issued. After each write, executing EWDS restores protection - preventing accidental overwrites during noise events or power transients. This feature is integral to the 93LC66CT-E/MS architecture and requires no external components.
What is the purpose of the DO pin on the 93LC66CT-E/MS?
The DO pin on the 93LC66CT-E/MS serves two distinct functions: during READ operations, it outputs serial data synchronized to CLK; during erase/write cycles, it provides Ready/Busy status - low indicates ongoing programming, high means complete. This dual-role design enables efficient polling without additional status lines. For the 93LC66CT-E/MS, DO enters High-Z when CS is low, ensuring clean bus sharing in multi-device configurations.
Can the 93LC66CT-E/MS operate at 2.5 V?
Yes, the 93LC66CT-E/MS is fully specified for operation from 2.5 V to 5.5 V. At 2.5 V, it supports clock frequencies up to 2 MHz, maintains 100 µA max read current (D9), and guarantees 6 ms write cycle time (TWC). Its low-voltage capability allows direct integration with 2.5 V or 3.3 V microcontrollers and battery-powered systems - a core design objective of the 93LC66CT-E/MS series.
Is the 93LC66CT-E/MS RoHS compliant and lead-free?
Yes, the 93LC66CT-E/MS is Pb-free and RoHS compliant, with a Matte Tin (Sn) finish per JEDEC standards. The 'T' in the part number denotes traceable production lot marking, and the MSOP-8 package meets J-STD-020 moisture sensitivity level 1 (MSL-1), allowing unlimited floor life at ≤30°C/60% RH. This compliance is confirmed in Microchip DS21795E and applies to all shipped units of the 93LC66CT-E/MS.
93LC66CT-E/MS Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- 8-TSSOP, 8-MSOP (0.118", 3.00mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Programmable:
- Not 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:
- 3 MHz
- Write Cycle Time - Word, Page:
- 6ms
- Access Time:
- -
- Voltage - Supply:
- 2.5V ~ 5.5V
- Operating Temperature:
- -40°C ~ 125°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 8-MSOP
93LC66CT-E/MS FAQ
1.How can I place an order for 93LC66CT-E/MS through Aetrix?
Please submit a Request for Quotation (RFQ) for 93LC66CT-E/MS 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 93LC66CT-E/MS reliable?
The price and inventory of 93LC66CT-E/MS are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 93LC66CT-E/MS is usually 5 days.
3.What payment methods are accepted for 93LC66CT-E/MS?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 93LC66CT-E/MS transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 93LC66CT-E/MS?
93LC66CT-E/MS orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 93LC66CT-E/MS 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 93LC66CT-E/MS?
For technical support, including 93LC66CT-E/MS datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 93LC66CT-E/MS requirements.
6.How does Aetrix verify that 93LC66CT-E/MS is sourced from the original manufacturer or authorized distributors?
All 93LC66CT-E/MS 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 93LC66CT-E/MS meets industry standards.
7.What is the process for return or replacement of 93LC66CT-E/MS?
All 93LC66CT-E/MS units undergo pre-shipment inspection (PSI). If there is an issue with 93LC66CT-E/MS, 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 93LC66CT-E/MS part is unused and in its original packaging.
Return procedure for 93LC66CT-E/MS:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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