My Inquiry
My Account
Microchip Technology 93LC66AX/SN
- Part No.:
- 93LC66AX/SN
- Manufacturer:
- Microchip Technology
- Category:
- Memory
- Package:
- 8-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
93LC66AX/SN.pdf
- Description:
- IC EEPROM 4KBIT MICROWIRE 8SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:1,153
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
93LC66AX/SN from Microchip Technology Inc. is a 4 Kbit (512 × 8-bit) low-voltage serial EEPROM with Microwire-compatible 3-wire interface, 2.5–5.5 V supply range, and industrial temperature grade (−40°C to +85°C). It features self-timed erase/write cycles, automatic ERAL/WRAL support, and Ready/Busy status signaling via DO pin - used for configuration storage in microcontroller-based embedded systems.
For engineers reviewing the 93LC66AX/SN datasheet, 93LC66AX/SN pinout, 93LC66AX/SN application, or 93LC66AX/SN equivalent, key selection criteria include its dedicated 8-bit organization (no ORG pin), SOIC-8 package compatibility, 1 million endurance cycles, 200-year data retention, and support for sequential read and write-all operations in space-constrained industrial control modules.
Technical Context
This device implements a synchronous serial Microwire interface with CS, CLK, and DI/DO pins - no internal address counter reset on CS deassertion, enabling continuous sequential reads. The absence of an ORG pin confirms fixed 8-bit word organization, eliminating external configuration logic required by 'C' variants.
It uses CMOS EEPROM technology with on-chip charge pump for write/erase, power-on/off protection circuitry, and automatic erase-before-write. Write cycle timing is self-timed at 6 ms (TWC), with status polling via DO pin after minimum TCSL (250 ns) - critical for deterministic firmware timing in real-time systems.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Memory Size | 4 Kbit (512 words × 8 bits) - fits calibration tables, device IDs, and small firmware patches in resource-limited MCUs. |
| VCC Range | 2.5 V to 5.5 V - interoperable with 3.3 V and 5 V logic domains without level shifters. |
| Endurance | 1,000,000 erase/write cycles - supports frequent field-updatable parameters in industrial sensors. |
| Data Retention | >200 years at 25°C - ensures long-term reliability in unattended equipment like metering or telemetry nodes. |
| Write Cycle Time | 6 ms typical (TWC) - enables predictable timeout handling in interrupt-driven drivers without busy-wait loops. |
| Interface | Microwire-compatible 3-wire serial (CS/CLK/DI/DO) - minimal GPIO usage; no SPI mode bits or frame sync overhead. |
| Temperature Range | Industrial: −40°C to +85°C - qualified for factory automation, motor drives, and outdoor control panels. |
Pinout & Package
93LC66AX/SN is supplied in 8-lead SOIC (SN) package per Microchip's DS21795E. Pin 1 is CS; pin 2 is CLK; pin 3 is DI; pin 4 is DO; pin 5 is VSS; pin 6 is NC (no internal connection); pin 7 is NC; pin 8 is VCC. ORG pin is absent - confirming fixed 8-bit organization.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| CS (Pin 1) | Chip Select | Active-high enable; must be held low ≥250 ns between instructions; initiates self-timed write on falling edge. |
| CLK (Pin 2) | Serial Clock | Synchronizes all data transfers; rising edge clocks in opcode/address/data; stoppable mid-sequence. |
| DI (Pin 3) | Data Input | Accepts Start bit, opcodes, addresses, and write data; shares no internal path with DO. |
| DO (Pin 4) | Data Output / Status | Outputs read data or Ready/Busy (low = busy); enters High-Z on CS falling edge. |
| VSS (Pin 5) | Ground | Reference for all I/O and internal circuitry; requires low-impedance connection to system ground plane. |
| NC (Pin 6 & 7) | No Internal Connection | Unbonded; must be left floating or tied to VSS - no routing or pull-up/pull-down required. |
| VCC (Pin 8) | Power Supply | Supplies core logic and charge pump; bypass capacitor (0.1 µF) mandatory within 10 mm of pin. |
Key Features
| Feature | Design Value |
|---|---|
| Self-timed Erase/Write | Eliminates external timing control - firmware only polls DO or waits fixed 6 ms; reduces driver complexity. |
| Automatic ERAL before WRAL | Ensures full-array writes always begin from erased state - prevents data corruption during bulk updates. |
| Power-On/Off Data Protection | Hardware lockout below VPOR = 1.5 V - prevents spurious writes during brown-out or hot-plug events. |
| Ready/Busy Status via DO | Enables non-blocking operation - MCU can execute other tasks while waiting for write completion. |
| Sequential Read Mode | Continuous clocking with CS held high auto-increments address - efficient for reading contiguous parameter blocks. |
Applications
| Industrial Sensor Calibration | Consumer Appliance Configuration |
|---|---|
Use Scenario: Storing temperature compensation coefficients and sensor offset values in HVAC thermostats and pressure transmitters. IC Role / Device Role / Timing Role: Nonvolatile configuration register accessed at boot and during field recalibration. Use Value: Maintains accuracy across power cycles and thermal cycling; 200-year retention avoids recalibration drift in sealed units. |
Use Scenario: Saving user preferences (e.g., wash cycle settings, display brightness) in washing machines and microwaves. IC Role / Device Role / Timing Role: Low-pin-count memory interfaced directly to 8-bit MCU GPIOs with minimal board area. Use Value: SOIC-8 footprint allows placement near MCU; 2.5 V operation matches modern low-power appliance controllers. |
| Medical Device Parameter Storage | Automotive Body Control Module |
Use Scenario: Holding safety-critical operational limits and calibration history logs in portable ECG monitors and infusion pumps. IC Role / Device Role / Timing Role: Secure, tamper-resistant storage with hardware write-protection (EWDS/EWEN commands). Use Value: 1M endurance supports daily recalibration logs over 10+ years; RoHS/Pb-free compliance meets medical regulatory requirements. |
Use Scenario: Storing door lock actuator profiles and lighting dimming curves in vehicle BCMs. IC Role / Device Role / Timing Role: Interface to CAN-linked microcontroller for configuration updates via diagnostic port. Use Value: Industrial temp grade ensures reliability under hood temperatures; 3-wire interface reduces harness complexity vs. I²C. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar serial EEPROM applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 93LC66B/SN | Fixed 256 × 16-bit organization; same VCC, timing, and package. | Requires 16-bit MCU interface or byte-swapping logic; not drop-in for 8-bit software stacks. | Select only if system architecture mandates 16-bit word access and firmware handles dual-byte alignment. |
| AT25040B-MAU-1.8 | SPI interface (4-wire), 1.8–5.5 V, 512 × 8-bit, 20 MHz max clock; no Ready/Busy pin. | Needs dedicated SPI peripheral; lacks hardware status polling - requires fixed 5 ms timeouts instead of dynamic DO polling. | Prefer when existing design uses SPI peripherals and deterministic worst-case timing suffices over status-driven efficiency. |
Compared with 93LC66B/SN, the 93LC66AX/SN provides native 8-bit compatibility and simpler driver code; versus AT25040B-MAU-1.8, it offers lower pin count and hardware-ready signaling - advantageous in GPIO-constrained, latency-sensitive embedded systems.
Availability
93LC66AX/SN is available at Aetrix Electronics and suitable for industrial sensor calibration, consumer appliance configuration, medical device parameter storage, and automotive body control module designs requiring stable component supply, long-life qualification, and RoHS-compliant sourcing.
Supply support for 93LC66AX/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 microcontrollers, analog components, and memory solutions, headquartered in Chandler, Arizona, with global manufacturing and support infrastructure.
The 93LC66AX/SN belongs to Microchip's legacy 93XX serial EEPROM family, designed specifically for cost-sensitive, low-power embedded systems requiring simple, robust nonvolatile storage with minimal external components.
FAQ
What is the memory organization of the 93LC66AX/SN?
The 93LC66AX/SN has a fixed 512 × 8-bit (4 Kbit) organization. Unlike 'C' variants, it lacks an ORG pin - confirming dedicated 8-bit word structure. This eliminates external configuration logic and simplifies firmware addressing, making it ideal for systems where byte-aligned data access is standard. The 93LC66AX/SN does not support 16-bit mode.
Does the 93LC66AX/SN support hardware write protection?
Yes, the 93LC66AX/SN implements Erase/Write Disable (EWDS) and Enable (EWEN) commands. It powers up in EWDS mode, blocking all programming until EWEN is issued. After each write, executing EWDS prevents accidental overwrites - a critical safeguard in field-deployed devices. The 93LC66AX/SN enforces this at the silicon level, independent of software state.
What is the maximum clock frequency supported by the 93LC66AX/SN?
The 93LC66AX/SN 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. Since the 93LC66AX/SN operates from 2.5–5.5 V, its practical maximum is 3 MHz. Timing margins must respect TCKH (200 ns min) and TCKL (100 ns min) per DS21795E.
Can the 93LC66AX/SN be used in automotive applications?
The 93LC66AX/SN is rated for Industrial temperature (−40°C to +85°C), not Automotive (−40°C to +125°C). While functionally identical to the automotive-grade 93LC66AE/SN, it lacks AEC-Q100 qualification and extended high-temp validation. For under-hood or safety-critical automotive use, the 93LC66AE/SN - not the 93LC66AX/SN - must be selected.
How does the Ready/Busy status work on the 93LC66AX/SN?
The 93LC66AX/SN signals Ready/Busy on the DO pin: logic low indicates ongoing erase/write, high indicates completion. To poll, hold CS low ≥250 ns (TCSL), then drive CS high - DO transitions within TSV (200–500 ns). Issuing a Start bit followed by CS low clears the status. This hardware signaling avoids fixed delays, improving real-time responsiveness in the 93LC66AX/SN.
93LC66AX/SN Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- 8-SOIC (0.154", 3.90mm Width)
- Packaging:
- Tube
- Product Status:
- Active
- Programmable:
- Not 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:
- Surface Mount
- Supplier Device Package:
- 8-SOIC
93LC66AX/SN FAQ
1.How can I place an order for 93LC66AX/SN through Aetrix?
Please submit a Request for Quotation (RFQ) for 93LC66AX/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 93LC66AX/SN reliable?
The price and inventory of 93LC66AX/SN are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 93LC66AX/SN is usually 5 days.
3.What payment methods are accepted for 93LC66AX/SN?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 93LC66AX/SN transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 93LC66AX/SN?
93LC66AX/SN orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 93LC66AX/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 93LC66AX/SN?
For technical support, including 93LC66AX/SN datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 93LC66AX/SN requirements.
6.How does Aetrix verify that 93LC66AX/SN is sourced from the original manufacturer or authorized distributors?
All 93LC66AX/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 93LC66AX/SN meets industry standards.
7.What is the process for return or replacement of 93LC66AX/SN?
All 93LC66AX/SN units undergo pre-shipment inspection (PSI). If there is an issue with 93LC66AX/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 93LC66AX/SN part is unused and in its original packaging.
Return procedure for 93LC66AX/SN:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
93LC66AX/SN Tags
-
M24C02-WMN6TP
STMicroelectronics
-
AT24C02C-XHM-T
Microchip Technology
-
AT21CS01-STUM10-T
Microchip Technology
-
AT24C02C-SSHM-T
Microchip Technology
-
24LC01BT-I/OT
Microchip Technology
-
M24C02-FMC6TG
STMicroelectronics
-
AT24CS02-SSHM-T
Microchip Technology
-
93LC46BT-I/OT
Microchip Technology
-
AT24C04C-SSHM-T
Microchip Technology
-
24LC01BT-I/SN
Microchip Technology
-
24AA02UIDT-I/OT
Microchip Technology
-
AT24C08C-STUM-T
Microchip Technology
Tech Hub
TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
