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Microchip Technology 93LC66A/P
- Part No.:
- 93LC66A/P
- Manufacturer:
- Microchip Technology
- Category:
- Memory
- Package:
- 8-DIP (0.300", 7.62mm)
- Datasheet:
-
93LC66A/P.pdf
- Description:
- IC EEPROM 4KBIT MICROWIRE 8DIP
- Quantity:
- Payment:
- Shipping:
Inventory:3,192
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Product details
Overview
The 93LC66A/P from Microchip Technology is a 4 Kbit (512 × 8-bit) low-voltage serial EEPROM with Microwire-compatible 3-wire interface, operating across 2.5–5.5 V, supporting Industrial (−40°C to +85°C) and Automotive (−40°C to +125°C) temperature ranges, and featuring self-timed erase/write cycles, automatic ERAL/WRAL, and Ready/Busy status signaling - used for nonvolatile parameter storage in microcontroller-based embedded systems.
For engineers reviewing the 93LC66A/P datasheet, 93LC66A/P pinout, 93LC66A/P application, or 93LC66A/P equivalent, this page delivers verified electrical specs, package-confirmed pin functions, real-world use cases, and validated alternative parts - all aligned to DS21795E revision E and Microchip's official packaging specifications.
Technical Context
The 93LC66A/P implements a synchronous serial Microwire protocol with CS, CLK, DI, and DO pins - no ORG pin (dedicated x8 organization). It uses internal auto-erase-before-write logic and supports sequential read, ERAL (Erase All), WRAL (Write All), EWEN/EWDS protection, and power-on data protection.
Its timing is defined by voltage-dependent clock frequency limits (up to 3 MHz at VCC ≥ 4.5 V), with TWC = 6 ms program cycle time, TEC = 6 ms ERAL, TWL = 15 ms WRAL, and guaranteed 1,000,000 erase/write cycles with >200-year data retention - all specified over full industrial and automotive temperature ranges.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Memory size | 4 Kbit (512 × 8-bit) - fixed x8 organization; no ORG pin required |
| VCC range | 2.5 V to 5.5 V - supports wide-input industrial and automotive power rails |
| Interface | 3-wire Microwire-compatible serial (CS/CLK/DI/DO) - no SPI or I²C protocol |
| Endurance | 1,000,000 erase/write cycles - validated at 25°C, VCC = 5.0 V per DS21795E |
| Data retention | >200 years - guaranteed under rated operating conditions |
| Temp range | Industrial: −40°C to +85°C; Automotive: −40°C to +125°C - dual-grade availability |
| Write time | 6 ms typical (TWC) - self-timed; no external delay needed in firmware |
Pinout & Package
Package: 8-lead PDIP (P suffix), Pb-free Matte Tin finish, through-hole mounting. Pin 1 marked by notch or dot; pin 1 ID confirmed per Microchip DS21795E-page 18.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| CS | Chip Select | Active-high enable; must be held low ≥250 ns between instructions (TCSL) |
| CLK | Serial Clock | Positive-edge synchronized I/O; stops/resumes freely during transmission |
| DI | Data Input | Accepts Start bit, opcode, address, and write data; no internal pull-up |
| DO | Data Output / Status | Outputs read data or Ready/Busy (low = busy); high-Z when CS low or idle |
| VSS | Ground | Reference for all I/O and internal logic; must be connected before VCC |
| NC | No Connection | Pin 7 in PDIP/SOIC - internally unconnected; must be left floating or tied to VSS |
| VCC | Power Supply | 2.5–5.5 V supply; POR threshold = 1.5 V; decoupling capacitor recommended |
| ORG | Not applicable | NC on 93LC66A - not bonded; no function; do not connect |
Key Features
| Feature | Design Value |
|---|---|
| Self-timed erase/write | Eliminates need for external timing control or firmware delays - TWC = 6 ms fixed |
| Automatic ERAL before WRAL | Ensures full-array write integrity without separate erase command in bootloaders |
| Ready/Busy via DO pin | Enables polling-based firmware flow control without interrupt or timer overhead |
| EWEN/EWDS data protection | Prevents accidental writes; device powers up in EWDS mode - explicit EWEN required |
| Pb-free & RoHS compliant | Meets global environmental compliance; Matte Tin (Sn) finish on all package variants |
Applications
| Industrial Sensor Calibration | Automotive Body Control Module |
|---|---|
Use Scenario: Storing factory-trimmed sensor offset/gain coefficients and runtime calibration updates in HVAC or pressure sensors. IC Role / Device Role / Timing Role: Nonvolatile parameter storage with infrequent writes and long-term retention; accessed via MCU GPIO bit-banged Microwire. Use Value: Eliminates need for battery-backed RAM; retains calibration across power cycles and 20+ year product life. | Use Scenario: Saving seat position memory, mirror settings, and lighting configuration in vehicle door modules. IC Role / Device Role / Timing Role: Dedicated x8 EEPROM interfaced to 8-bit MCU over 3-wire bus; operates across −40°C to +125°C ambient. Use Value: Meets AEC-Q100 Grade 1 requirements; withstands automotive thermal cycling without data loss. |
| Medical Infusion Pump Settings | Smart Energy Meter Firmware Patch Storage |
Use Scenario: Holding user-defined dosing profiles, alarm thresholds, and audit logs in Class II medical devices. IC Role / Device Role / Timing Role: Secure, tamper-resistant storage with EWEN/EWDS lock; accessed only during service mode. Use Value: Supports IEC 62304 software lifecycle requirements; 1M endurance enables field update logging. | Use Scenario: Storing firmware patch binaries and version metadata in utility meters deployed for 15+ years. IC Role / Device Role / Timing Role: High-reliability backup storage for critical firmware fragments; accessed during OTA update verification. Use Value: >200-year data retention ensures patch validity over full meter lifetime without refresh. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar serial EEPROM applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 93LC66B/P | 16-bit organization (256 × 16), same VCC/temp range; no ORG pin - fixed x16 word size | Requires 16-bit MCU data path or byte-swapping firmware; incompatible with x8-only drivers | Select only if system architecture mandates 16-bit word access and eliminates byte alignment overhead |
| AT25040B-MAHL-T | SPI interface (4-wire), 4 Kbit (512 × 8), 1.8–5.5 V, same endurance/retention; no Ready/Busy pin | Needs SPI peripheral instead of bit-banged Microwire; lacks DO-based polling - requires timeout-based wait | Choose when migrating to SPI infrastructure or when pin count allows extra CS/SCK/MOSI/MISO |
Compared with 93LC66B/P, the 93LC66A/P avoids word-size conversion logic; compared with AT25040B-MAHL-T, it provides hardware-ready status signaling and simpler GPIO-driven interface - critical for resource-constrained 8-bit MCUs.
Availability
The 93LC66A/P is available at Aetrix Electronics and suitable for industrial sensor calibration, automotive body control modules, and medical infusion pump settings requiring stable component supply across extended product lifecycles.
Supply support for 93LC66A/P 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 microcontrollers, analog, and Flash-IP solutions, headquartered in Chandler, Arizona, serving industrial, automotive, and consumer markets since 1989.
The 93LC66A/P belongs to Microchip's legacy 93XX serial EEPROM family, designed specifically for low-pin-count, low-power, nonvolatile memory in cost-sensitive embedded systems where Microwire compatibility and robust data retention are essential.
FAQ
What is the memory organization and capacity of the 93LC66A/P?
The 93LC66A/P is a 4 Kbit serial EEPROM with fixed 512 × 8-bit organization - no ORG pin, no x16 mode. It stores 512 bytes of user data, addressed using 9-bit addresses (A0–A8), and is optimized for byte-oriented access in 8-bit microcontroller systems.
Does the 93LC66A/P require an external ORG connection?
No - the 93LC66A/P has no functional ORG pin; it is internally configured for x8 operation only. Pin 6 in PDIP/SOIC packages is NC (no internal connection), and must remain unconnected or tied to VSS per Microchip DS21795E.
What is the maximum clock frequency supported by the 93LC66A/P?
The 93LC66A/P supports up to 3 MHz clock frequency when VCC ≥ 4.5 V, 2 MHz at 2.5 V ≤ VCC < 4.5 V, and 1 MHz at 1.8 V ≤ VCC < 2.5 V - though its minimum VCC is 2.5 V, so 1 MHz operation does not apply to this part.
How does the Ready/Busy status work on the 93LC66A/P DO pin?
During erase or write operations, the DO pin outputs low (0 V) while busy and high (VCC) when complete - but only if CS is brought high for ≥250 ns after TCSL. If CS remains low, DO stays high-Z; status polling must follow the timing sequence in DS21795E Figures 2-1 and 2-8.
Is the 93LC66A/P suitable for automotive applications?
Yes - the 93LC66A/P is qualified for Automotive Grade E (−40°C to +125°C) operation, with validated performance across its full VCC range (2.5–5.5 V) and compliance to AEC-Q100 stress test requirements per Microchip's documentation.
93LC66A/P Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- 8-DIP (0.300", 7.62mm)
- Packaging:
- Tube
- Product Status:
- Active
- Programmable:
- Verified
- Memory Type:
- Non-Volatile
- Memory Format:
- EEPROM
- Technology:
- EEPROM
- Memory Size:
- 4Kbit
- Memory Organization:
- 512 x 8
- Memory Interface:
- Microwire
- Clock Frequency:
- 2 MHz
- Write Cycle Time - Word, Page:
- 6ms
- Access Time:
- -
- Voltage - Supply:
- 2.5V ~ 5.5V
- Operating Temperature:
- 0°C ~ 70°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- 8-PDIP
93LC66A/P FAQ
1.How can I place an order for 93LC66A/P through Aetrix?
Please submit a Request for Quotation (RFQ) for 93LC66A/P 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 93LC66A/P reliable?
The price and inventory of 93LC66A/P are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 93LC66A/P is usually 5 days.
3.What payment methods are accepted for 93LC66A/P?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 93LC66A/P transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 93LC66A/P?
93LC66A/P orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 93LC66A/P 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 93LC66A/P?
For technical support, including 93LC66A/P datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 93LC66A/P requirements.
6.How does Aetrix verify that 93LC66A/P is sourced from the original manufacturer or authorized distributors?
All 93LC66A/P 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 93LC66A/P meets industry standards.
7.What is the process for return or replacement of 93LC66A/P?
All 93LC66A/P units undergo pre-shipment inspection (PSI). If there is an issue with 93LC66A/P, 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 93LC66A/P part is unused and in its original packaging.
Return procedure for 93LC66A/P:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
93LC66A/P Tags
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M24C02-WMN6TP
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AT24C02C-XHM-T
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AT21CS01-STUM10-T
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AT24CS02-SSHM-T
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