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Microchip Technology 93LC66B/ST
- Part No.:
- 93LC66B/ST
- Manufacturer:
- Microchip Technology
- Category:
- Memory
- Package:
- 8-TSSOP (0.173", 4.40mm Width)
- Datasheet:
-
93LC66B/ST.pdf
- Description:
- IC EEPROM 4KBIT MICROWIRE 8TSSOP
- Quantity:
- Payment:
- Shipping:
Inventory:1,801
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Product details
Overview
93LC66B/ST from Microchip Technology Inc. is a 4Kbit, 256 x 16-bit organization, low-voltage serial EEPROM with Microwire-compatible 3-wire interface, 2.5–5.5V supply range, and industrial temperature grade (–40°C to +85°C). It features self-timed erase/write cycles, automatic ERAL before WRAL, Ready/Busy status via DO pin, and 1,000,000 endurance cycles - deployed in embedded system configuration storage.
For engineers reviewing the 93LC66B/ST datasheet, 93LC66B/ST pinout, 93LC66B/ST application, or 93LC66B/ST equivalent, key selection criteria include guaranteed 16-bit word access without ORG pin dependency, TSSOP-8 package compatibility, VCC=2.5V minimum operation, and support for sequential read and WRAL with auto-ERAL.
Technical Context
The 93LC66B/ST implements a synchronous serial Microwire protocol with dedicated 16-bit memory mapping (256 words × 16 bits), eliminating need for external ORG pin control. Its instruction set includes READ (20 CLK cycles), WRITE (20 CLK cycles), ERASE (12 CLK cycles), ERAL (12 CLK cycles), and WRAL (20 CLK cycles), all initiated by CS falling edge for AA/LC variants.
Power-on data protection is enforced via internal voltage detect at 1.5V threshold; standby current is ≤5 µA at 2.5V. The device supports sequential read when CS remains high, and Ready/Busy polling via DO pin after TCSL ≥250 ns - critical for deterministic firmware timing in microcontroller-based systems.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Memory Size | 4 Kbit (256 × 16-bit words) - fixed 16-bit organization; no ORG pin required. |
| VCC Range | 2.5 V to 5.5 V - supports single-supply operation in 3.3V and 5V systems. |
| Endurance | 1,000,000 erase/write cycles - enables long-term field calibration and parameter logging. |
| Data Retention | >200 years at 25°C - ensures nonvolatile storage integrity across product lifecycle. |
| Write Cycle Time | 6 ms typical - self-timed; eliminates need for external timing control in host firmware. |
| Max Clock Frequency | 3 MHz at VCC ≥4.5V; 2 MHz at VCC ≥2.5V - defines maximum SPI-like throughput for configuration updates. |
| Temperature Range | –40°C to +85°C (Industrial) - qualified for industrial control, metering, and automotive body electronics. |
Pinout & Package
93LC66B/ST is supplied in an 8-pin TSSOP (Thin Shrink Small Outline Package) with 0.65 mm pitch, JEDEC MO-153 compliant, and Pb-free Matte Tin finish. Pin 1 marked by laser dot; exposed pad not present.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| CS | Chip Select | Active-high enable; must be held low ≥250 ns between instructions; initiates self-timed write on falling edge. |
| CLK | Serial Clock | Synchronizes all data transfers; rising edge clocks in opcode/address/data; stoppable mid-sequence. |
| DI | Data Input | Accepts Start bit, opcode, address, and 16-bit write data; requires pull-up for reliable start detection. |
| DO | Data Output / Status | Outputs 16-bit read data or Ready/Busy (low = busy); enters High-Z on CS falling edge. |
| VSS | Ground | Reference for all I/O and internal logic; must be connected directly to system ground plane. |
| NC | No Connect | Pin 7 is internally unconnected; must be left floating or tied to VSS per layout best practice. |
| VCC | Power Supply | 2.5–5.5V supply; internal POR circuit triggers at ~1.5V; decoupling capacitor required. |
| ORG | Organization Select | Not implemented on 93LC66B; pin 6 is NC - device permanently configured for 16-bit mode. |
Key Features
| Feature | Design Value |
|---|---|
| Self-timed Erase/Write | Eliminates host MCU timing overhead; 6 ms typical cycle time ensures deterministic firmware execution. |
| Automatic ERAL before WRAL | Guarantees full-array readiness prior to bulk write; prevents partial writes and data corruption. |
| Ready/Busy Status via DO | Enables polled operation without interrupts; reduces GPIO count and simplifies driver implementation. |
| Industry-standard 3-wire interface | Direct drop-in replacement for legacy Microwire EEPROMs; minimal PCB redesign required. |
| Power-On/Off Data Protection | Hardware-enforced write inhibition below 1.5V VCC; prevents inadvertent writes during brown-out conditions. |
Applications
| Industrial Sensor Calibration | Automotive Body Control Module |
|---|---|
Use Scenario: Storing factory-trimmed sensor offset/gain coefficients and real-time calibration updates in pressure/temperature transducers. IC Role / Device Role / Timing Role: Nonvolatile configuration register accessed during power-up and periodic recalibration routines. Use Value: 256 × 16-bit capacity stores 16+ calibration parameters with redundancy; 1M endurance supports field recalibration over 10+ years. | Use Scenario: Holding seat position memory, mirror angle presets, and lighting configuration in vehicle door modules. IC Role / Device Role / Timing Role: Dedicated 16-bit serial EEPROM interfaced to 8-bit microcontroller via bit-banged Microwire. Use Value: TSSOP-8 footprint fits space-constrained door ECUs; –40°C to +85°C rating matches under-hood ambient requirements. |
| Smart Energy Meter Firmware Settings | Medical Infusion Pump Parameter Storage |
Use Scenario: Retaining tariff schedules, pulse constants, and communication settings across power cycles in ANSI C12.22-compliant meters. IC Role / Device Role / Timing Role: Secure configuration store accessed only during meter initialization or authenticated firmware update. Use Value: >200-year data retention meets utility 20-year deployment mandates; 2.5V min VCC supports battery-backed operation. | Use Scenario: Saving drug library profiles, flow rate limits, and alarm thresholds in Class II medical devices requiring traceable parameter history. IC Role / Device Role / Timing Role: Safety-critical nonvolatile memory with write-protection enforced by EWEN/EWDS command sequence. Use Value: Hardware-level write disable (EWDS) prevents accidental overwrite during runtime; RoHS/Pb-free compliance satisfies IEC 60601-1. |
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 | Same die, SOIC-8 package (5.3mm × 4.4mm vs TSSOP-8's 3.0mm × 4.4mm); identical electrical specs and timing. | Preferred where board space allows larger footprint and hand-soldering is used. | Select 93LC66B/SN for prototyping or low-volume assembly; 93LC66B/ST for space-constrained production boards. |
| AT25040B-SSHL-B | 4Kbit SPI EEPROM (8-bit only), 1.8–5.5V, 20 MHz max clock; lacks WRAL/ERAL and 16-bit native access. | Requires software bit-packing for 16-bit values; higher throughput but less deterministic write latency. | Choose AT25040B only if SPI interface is already standardized in design and 16-bit atomic writes are unnecessary. |
Compared with 93LC66B/SN, the 93LC66B/ST offers identical functionality in a 40% smaller footprint; versus AT25040B-SSHL-B, it provides native 16-bit access and guaranteed auto-ERAL, reducing firmware complexity for configuration management.
Availability
93LC66B/ST is available at Aetrix Electronics and suitable for industrial sensor calibration, automotive body control modules, and smart energy meter firmware settings requiring stable component supply and long-term obsolescence management.
Supply support for 93LC66B/ST 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 design and manufacturing operations.
The 93LCxx series was designed specifically for cost-sensitive, low-power embedded systems requiring reliable serial nonvolatile storage with minimal pin count and firmware overhead.
FAQ
What is the memory organization of the 93LC66B/ST?
The 93LC66B/ST has a fixed 256 × 16-bit organization (4 Kbit total), with no ORG pin dependency. Unlike 'C' variants, it permanently operates in 16-bit mode - eliminating external configuration logic and simplifying PCB layout. This architecture delivers native 16-bit parameter storage ideal for microcontrollers with 16-bit registers or aligned data structures. The 93LC66B/ST does not support 8-bit mode.
Does the 93LC66B/ST require an external ORG pin connection?
No, the 93LC66B/ST does not require an ORG pin connection because it is a 'B'-suffix device with fixed 16-bit organization. Pin 6 is designated NC (No Connect) per the datasheet, and internal logic is hardwired for x16 operation. Connecting ORG to any voltage violates the pin description and may cause undefined behavior. The 93LC66B/ST functions correctly with only CS, CLK, DI, DO, VCC, and VSS connected.
What is the minimum VCC required for reliable operation of the 93LC66B/ST?
The 93LC66B/ST requires a minimum VCC of 2.5 V for full specification compliance across the industrial temperature range (–40°C to +85°C). Below 2.5 V, DC and AC parameters are not guaranteed; the internal voltage detector disables write operations below ~1.5 V to prevent data corruption. For battery-powered applications, ensure VCC remains ≥2.5 V during active read/write cycles - the 93LC66B/ST draws ≤5 µA in standby at 2.5 V.
How does the Ready/Busy status work on the 93LC66B/ST?
The 93LC66B/ST asserts Ready/Busy status on the DO pin: logic low indicates ongoing erase/write, logic high signals completion. To poll status, hold CS high for ≥250 ns after initiating a command, then sample DO on the next CLK rising edge. DO returns to High-Z on CS falling edge. This mechanism enables interrupt-free firmware polling - critical for real-time systems where 93LC66B/ST write latency (6 ms typical) must be managed deterministically.
Is the 93LC66B/ST RoHS compliant and Pb-free?
Yes, the 93LC66B/ST is RoHS compliant and Pb-free, with a Matte Tin (Sn) finish per JEDEC J-STD-609. The "ST" suffix explicitly denotes the TSSOP-8 package with Pb-free plating. All 93LC66B/ST units shipped by Aetrix Electronics meet EU Directive 2011/65/EU and are suitable for consumer, industrial, and medical applications requiring halogen-free and lead-free construction. Full compliance documentation is available upon request.
93LC66B/ST Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- 8-TSSOP (0.173", 4.40mm Width)
- Packaging:
- Tube
- Product Status:
- Active
- Programmable:
- Verified
- Memory Type:
- Non-Volatile
- Memory Format:
- EEPROM
- Technology:
- EEPROM
- Memory Size:
- 4Kbit
- Memory Organization:
- 256 x 16
- 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-TSSOP
93LC66B/ST FAQ
1.How can I place an order for 93LC66B/ST through Aetrix?
Please submit a Request for Quotation (RFQ) for 93LC66B/ST 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 93LC66B/ST reliable?
The price and inventory of 93LC66B/ST are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 93LC66B/ST is usually 5 days.
3.What payment methods are accepted for 93LC66B/ST?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 93LC66B/ST transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 93LC66B/ST?
93LC66B/ST orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 93LC66B/ST 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 93LC66B/ST?
For technical support, including 93LC66B/ST datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 93LC66B/ST requirements.
6.How does Aetrix verify that 93LC66B/ST is sourced from the original manufacturer or authorized distributors?
All 93LC66B/ST 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 93LC66B/ST meets industry standards.
7.What is the process for return or replacement of 93LC66B/ST?
All 93LC66B/ST units undergo pre-shipment inspection (PSI). If there is an issue with 93LC66B/ST, 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 93LC66B/ST part is unused and in its original packaging.
Return procedure for 93LC66B/ST:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
93LC66B/ST Tags
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M24C02-WMN6TP
STMicroelectronics
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AT24C02C-XHM-T
Microchip Technology
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AT21CS01-STUM10-T
Microchip Technology
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AT24C02C-SSHM-T
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24LC01BT-I/OT
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M24C02-FMC6TG
STMicroelectronics
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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
Microchip Technology
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