My Inquiry
My Account
Microchip Technology AT25640B-XHL-T
- Part No.:
- AT25640B-XHL-T
- Manufacturer:
- Microchip Technology
- Category:
- Memory
- Package:
- 8-TSSOP (0.173", 4.40mm Width)
- Datasheet:
-
AT25640B-XHL-T.pdf
- Description:
- IC EEPROM 64KBIT SPI 8TSSOP
- Quantity:
- Payment:
- Shipping:
Inventory:35,092
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
AT25640B-XHL-T from Microchip Technology (formerly Atmel) is a 64Kb SPI Serial EEPROM organized as 8,192 words × 8 bits, operating from 1.8V to 5.5V with 20MHz max clock rate at 5V, 32-byte page write capability, and hardware/software write protection via WP pin and status register - used for firmware parameter storage in industrial controllers and embedded telemetry modules.
For engineers reviewing the AT25640B-XHL-T datasheet, AT25640B-XHL-T pinout, AT25640B-XHL-T application, or AT25640B-XHL-T equivalent, key selection criteria include industrial temperature range (−40°C to +85°C), JEDEC-compliant TSSOP-8 package, 1M write cycle endurance, 100-year data retention, and support for SPI Modes 0 and 3 with HOLD/CS-controlled serial suspension.
Technical Context
The AT25640B-XHL-T implements a synchronous slave SPI interface with separate SI/SO lines, MSB-first data transfer, and opcode-driven command execution (e.g., WREN, WRITE, RDSR). It features an internal address counter that auto-increments during sequential reads and wraps on overflow.
Its nonvolatile status register controls block write protection (BP0/BP1) across four memory segments and enables/disables hardware write protection via the WPEN bit. The HOLD pin suspends ongoing serial communication without resetting the sequence when asserted low during SCK low time.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Memory Density | 65,536 bits (8,192 × 8), enabling storage of configuration tables or calibration data for mid-complexity embedded systems |
| Supply Voltage Range | 1.8V to 5.5V - supports direct interfacing with 1.8V, 3.3V, and 5V microcontrollers without level-shifting |
| Max Clock Frequency | 20 MHz at VCC = 5V - delivers up to 2.5 MB/s effective serial throughput for rapid parameter updates |
| Write Cycle Time | 5 ms maximum - defines worst-case latency for single-byte or page-write operations |
| Endurance & Retention | 1,000,000 write cycles / 100 years data retention - ensures long-term reliability in field-deployed equipment |
| Operating Temperature | −40°C to +85°C - qualified for industrial-grade operation without derating |
| Interface Protocol | SPI Mode 0 (CPOL=0, CPHA=0) and Mode 3 (CPOL=1, CPHA=1) - compatible with broad MCU ecosystem including ARM Cortex-M and legacy 8-bit controllers |
Pinout & Package
AT25640B-XHL-T is packaged in an 8-lead TSSOP (8X) per JEDEC MO-153, 4.4mm body width, NiPdAu lead finish, green/RoHS-compliant.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| CS | Chip Select | Active-low enable signal; must be held low for entire instruction sequence; high impedance on SO when CS is high |
| SCK | Serial Clock | Input-only clock; timing reference for SI sampling and SO output; supports up to 20MHz at 5V |
| SI | Serial Data Input | MOSI input carrying opcodes, addresses, and write data; MSB-first, sampled on SCK rising edge in Mode 0 |
| SO | Serial Data Output | MISO output delivering read data and status register contents; high-impedance when CS is high or HOLD is active |
| GND | Ground Reference | 0V return path for all I/O and power; requires low-impedance PCB connection to minimize noise coupling |
| VCC | Power Supply | 1.8–5.5V supply; decoupling capacitor (0.1 µF ceramic) required within 10 mm of VCC/GND pins |
| WP | Write Protect | Hardware lock for status register writes when WPEN=1; tied low to prevent accidental reconfiguration of BP bits |
| HOLD | Communication Suspend | Pauses ongoing SPI transaction without resetting state; must be asserted during SCK low time to avoid bus contention |
Key Features
| Feature | Design Value |
|---|---|
| 32-byte Page Write | Enables burst programming of up to 32 consecutive bytes with single CS assertion, reducing host MCU overhead vs. byte-wise writes |
| Four-Level Block Protection | Configurable via BP0/BP1 bits to protect 0%, 25%, 50%, or 100% of memory array - prevents corruption of critical boot parameters |
| Self-Timed Internal Write | No external erase cycle needed; device manages tWC (5ms max) autonomously, freeing host CPU during programming |
| Dual Write Protection Scheme | Combines hardware (WP pin) and software (WREN/WRSR) controls - allows system-level lockdown while retaining field-upgrade flexibility |
| Industrial Temperature Range | Validated operation from −40°C to +85°C ensures stable timing margins and data integrity in uncontrolled environments |
Applications
| Industrial PLC Configuration Storage | Medical Device Calibration Data |
|---|---|
Use Scenario: Storing I/O mapping, scaling factors, and alarm thresholds in programmable logic controllers deployed in factory automation cabinets. IC Role / Device Role / Timing Role: Nonvolatile parameter repository accessed infrequently but requiring guaranteed write integrity during power loss events. Use Value: 1M endurance and 100-year retention ensure calibration data survives decades of maintenance cycles without degradation. | Use Scenario: Holding sensor offset/gain coefficients and regulatory compliance logs in portable diagnostic instruments subject to periodic recalibration. IC Role / Device Role / Timing Role: Secure, tamper-resistant storage for FDA-mandated calibration history with hardware write lock enabled during clinical use. Use Value: WP pin + WPEN bit allows permanent lockdown of calibration registers while permitting runtime read access for diagnostics. |
| Smart Energy Meter Firmware Flags | Automotive Body Control Module Settings |
Use Scenario: Recording tariff schedules, meter ID, and firmware revision flags in ANSI C12.22-compliant electricity meters operating in outdoor enclosures. IC Role / Device Role / Timing Role: Low-power SPI EEPROM interfaced to an 8-bit MCU, accessed only during meter initialization or firmware update. Use Value: 1.8V operation enables direct connection to battery-backed MCU rails, eliminating voltage translation circuitry. | Use Scenario: Storing seat position presets, mirror angles, and lighting profiles in automotive BCMs where EEPROM must survive cold-cranking transients. IC Role / Device Role / Timing Role: Robust nonvolatile memory with fast 5ms write cycle and HOLD pin support for interrupt-safe parameter updates during CAN message handling. Use Value: HOLD functionality allows MCU to pause EEPROM writes mid-sequence when servicing high-priority CAN frames, preventing data corruption. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar SPI EEPROM applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| M95640-DRMN6TP/K | 64Kb SPI EEPROM, same 8-lead TSSOP package, 20MHz max clock, but rated for −40°C to +125°C and uses different status register layout | Higher temperature grade suits under-hood automotive use; lacks HOLD pin, limiting interrupt-safe operation in real-time systems | Select when extended temperature range is mandatory and HOLD functionality is not required |
| BR24G64FJ-WE2 | 64Kb I²C EEPROM in 8-lead TSSOP, 1MHz max clock, 1.7–5.5V supply, no HOLD or WP pins | I²C interface reduces pin count but halves effective throughput vs. SPI; no hardware write protection or suspend capability | Select for space-constrained designs where I²C bus already exists and lower write frequency is acceptable |
Compared with M95640-DRMN6TP/K and BR24G64FJ-WE2, the AT25640B-XHL-T provides unique HOLD pin support for deterministic interrupt handling and dual-mode SPI compatibility, making it optimal for real-time embedded systems requiring both robustness and host-CPU efficiency.
Availability
AT25640B-XHL-T is available at Aetrix Electronics and suitable for industrial control systems, medical instrumentation, smart metering, and automotive body electronics requiring stable component supply across extended product lifecycles.
Supply support for AT25640B-XHL-T 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 acquired Atmel in 2016 and integrates its legacy serial EEPROM portfolio into a unified memory solutions offering with global manufacturing and quality assurance.
The AT25640B-XHL-T belongs to Microchip's industrial-grade SPI EEPROM product line, designed specifically for reliable nonvolatile data storage in harsh environments where power interruption, temperature extremes, and long service life are critical requirements.
FAQ
What is the maximum clock frequency supported by the AT25640B-XHL-T at 3.3V operation?
The AT25640B-XHL-T supports up to 10 MHz SCK frequency when VCC = 2.5V to 5.5V, per Table 4-3 AC Characteristics. At 3.3V, this 10 MHz limit applies - not the 20 MHz maximum specified only for VCC = 4.5–5.5V. This ensures timing margin compliance across voltage ranges without requiring dynamic clock scaling in the host controller.
Does the AT25640B-XHL-T require an external pull-up resistor on the SO pin?
No, the AT25640B-XHL-T does not require an external pull-up on SO. Its SO pin is actively driven high or low during read operations and enters high-impedance state when CS is high or HOLD is asserted. External pull-ups may cause bus contention and violate the SO output specification (VOH/ VOL levels defined under load conditions).
How does the HOLD pin function during a write cycle in the AT25640B-XHL-T?
The HOLD pin remains fully functional during an internal write cycle in the AT25640B-XHL-T: asserting HOLD low pauses serial communication, but the self-timed 5ms write continues uninterrupted. After HOLD is de-asserted, the device resumes normal SPI operation - however, no new commands except RDSR are accepted until the write completes and RDY bit clears.
Can the AT25640B-XHL-T be used with an SPI master configured for Mode 1 or Mode 2?
No, the AT25640B-XHL-T explicitly supports only SPI Modes 0 (CPOL=0, CPHA=0) and 3 (CPOL=1, CPHA=1), as stated in the datasheet Features section. Modes 1 and 2 violate setup/hold timing requirements for SI and SO relative to SCK edges and will result in corrupted data transfers or opcode misinterpretation.
What is the purpose of the WPEN bit in the AT25640B-XHL-T status register?
WPEN (Write Protect Enable) bit in the AT25640B-XHL-T status register controls whether the WP pin affects status register writes. When WPEN = 1, pulling WP low blocks all status register modifications (including BP0/BP1 and WPEN itself); when WPEN = 0, the WP pin is ignored, allowing full software control even if physically tied low - enabling flexible system integration.
AT25640B-XHL-T Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- 8-TSSOP (0.173", 4.40mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Programmable:
- Verified
- Memory Type:
- Non-Volatile
- Memory Format:
- EEPROM
- Technology:
- EEPROM
- Memory Size:
- 64Kbit
- Memory Organization:
- 8K x 8
- Memory Interface:
- SPI
- Clock Frequency:
- 20 MHz
- Write Cycle Time - Word, Page:
- 5ms
- Access Time:
- -
- Voltage - Supply:
- 1.8V ~ 5.5V
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 8-TSSOP
AT25640B-XHL-T FAQ
1.How can I place an order for AT25640B-XHL-T through Aetrix?
Please submit a Request for Quotation (RFQ) for AT25640B-XHL-T 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 AT25640B-XHL-T reliable?
The price and inventory of AT25640B-XHL-T are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AT25640B-XHL-T is usually 5 days.
3.What payment methods are accepted for AT25640B-XHL-T?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AT25640B-XHL-T transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AT25640B-XHL-T?
AT25640B-XHL-T orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AT25640B-XHL-T 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 AT25640B-XHL-T?
For technical support, including AT25640B-XHL-T datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AT25640B-XHL-T requirements.
6.How does Aetrix verify that AT25640B-XHL-T is sourced from the original manufacturer or authorized distributors?
All AT25640B-XHL-T 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 AT25640B-XHL-T meets industry standards.
7.What is the process for return or replacement of AT25640B-XHL-T?
All AT25640B-XHL-T units undergo pre-shipment inspection (PSI). If there is an issue with AT25640B-XHL-T, 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 AT25640B-XHL-T part is unused and in its original packaging.
Return procedure for AT25640B-XHL-T:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
AT25640B-XHL-T 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…
