My Inquiry
My Account
Microchip Technology AT34C02D-SSHM-T
- Part No.:
- AT34C02D-SSHM-T
- Manufacturer:
- Microchip Technology
- Category:
- Memory
- Package:
- 8-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
AT34C02D-SSHM-T.pdf
- Description:
- IC EEPROM 2KBIT I2C 1MHZ 8SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:13,171
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
AT34C02D-SSHM-T from Microchip Technology (formerly Atmel) is a JEDEC EE1002/EE1002A-compliant Serial Presence Detect (SPD) EEPROM for DDR/DDR2/DDR3 DIMM modules, delivering 2 Kbit (256 × 8) nonvolatile memory with I²C-compatible 2-wire interface, 1.7–5.5 V operation, and hardware/software write protection. It supports 400 kHz (1.7–3.6 V) and 1 MHz (5.0 V) clock rates and is packaged in 8-lead JEDEC SOIC.
For engineers reviewing the AT34C02D-SSHM-T datasheet, AT34C02D-SSHM-T pinout, AT34C02D-SSHM-T application, or AT34C02D-SSHM-T equivalent, this device serves as a standardized SPD memory for memory module configuration storage-requiring precise voltage tolerance, SPD protocol compliance, page-write capability, and dual-layer write protection for system BIOS and memory controller initialization.
Technical Context
The AT34C02D-SSHM-T implements a dedicated SPD EEPROM architecture with hardwired A0–A2 address inputs enabling up to eight devices on one I²C bus, and a dedicated WP pin for hardware-level full-array write inhibition. Its internal organization comprises 16 pages of 16 bytes each, supporting partial and full-page writes with automatic address incrementing within page boundaries.
It integrates Schmitt-trigger filtered SCL/SDA inputs for noise immunity, self-timed 5 ms max write cycles, and dual software write protection modes-permanent (irreversible, lower 128 bytes) and reversible (programmable via specific command sequences)-all operating independently of WP pin state when WP = GND/floating.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Memory Size | 2,048 bits (256 × 8), organized as 16 pages × 16 bytes - enables full SPD data block storage per JEDEC specification. |
| Supply Voltage Range | 1.7 V to 5.5 V - supports interoperability across DDR1–DDR3 DIMM power rails including 2.5 V and 3.3 V systems. |
| I²C Clock Frequency | 400 kHz (1.7–3.6 V), 1 MHz (5.0 V) - ensures timing compliance with SPD read during memory initialization under varying VCC conditions. |
| Write Cycle Time | ≤ 5 ms - defines minimum inter-write interval; critical for SPD programming sequences during module manufacturing or field updates. |
| Endurance & Retention | 1,000,000 write cycles / 100 years data retention - guarantees long-term reliability for infrequent but mission-critical SPD configuration writes. |
| Write Protection | Hardware (WP pin → VCC) + permanent/reversible software modes - allows flexible protection of SPD header (lower 128 B) vs. user-configurable fields. |
| Operating Temperature | −40 °C to +85 °C - qualified for industrial-grade DIMM operation in server, networking, and embedded computing environments. |
Pinout & Package
AT34C02D-SSHM-T is supplied in an 8-lead JEDEC-standard SOIC package (package code SS, body width 0.150", 8S1). Pin 1 is located at the top-left corner with notch or dot marking.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| A0–A2 | Device Address Inputs | Hardwired to GND/VCC to set 3-bit hardware address; enables up to eight AT34C02D-SSHM-T devices on one I²C bus without address conflict. |
| GND | Ground Reference | System return path for VCC and I/O; must be low-impedance to ensure stable SPD read/write timing and noise immunity. |
| SDA | Serial Data Line | Bidirectional open-drain I²C data line; requires external pull-up; shared across multiple SPD devices on DIMM SMBus. |
| SCL | Serial Clock Input | Master-generated clock for I²C transactions; Schmitt-trigger input rejects noise during memory controller polling. |
| WP | Hardware Write Protect | Active-high signal: tied to VCC to disable all writes (including software protection setup); tied to GND/floating to enable software control. |
| VCC | Power Supply | Single-supply input (1.7–5.5 V); powers internal HV pump for EEPROM programming; decoupling capacitor required per JEDEC SPD layout guidelines. |
Key Features
| Feature | Design Value |
|---|---|
| JEDEC EE1002/EE1002A SPD Compliance | Fully implements mandatory SPD byte map, timing, and addressing for DDR/DDR2/DDR3 DIMMs - ensures plug-and-play compatibility with standard memory controllers and BIOS. |
| Dual Software Write Protection | Permanent mode locks lower 128 bytes (SPD header) irreversibly; reversible mode allows dynamic enable/disable of same region - prevents accidental corruption while permitting field updates to user fields. |
| Page Write with Roll-Over Handling | Supports up to 16-byte writes within a page; address auto-increments and wraps within page - simplifies SPD data loading without requiring complex address management in host firmware. |
| Wide-Voltage I²C Interface | Operates at 400 kHz down to 1.7 V and 1 MHz at 5.0 V - eliminates need for level-shifting circuitry across DDR generations and platform voltage domains. |
| High-Reliability Nonvolatile Storage | 1M write cycles and 100-year data retention - exceeds JEDEC SPD lifetime requirements for server and telecom applications where DIMMs remain in service >10 years. |
Applications
| DDR3 Server Memory Modules | Industrial DDR2 DIMMs |
|---|---|
Use Scenario: Storing SPD data (module type, speed, timings, manufacturer info) on registered DDR3 RDIMMs used in enterprise servers. IC Role / Device Role / Timing Role: SPD EEPROM providing standardized configuration data to memory controller during power-on initialization sequence. Use Value: Enables automatic memory training and JEDEC-compliant boot without manual BIOS configuration; AT34C02D-SSHM-T's 1.7–5.5 V range supports both 1.5 V DDR3 and 3.3 V SMBus logic. |
Use Scenario: Configuring unbuffered DDR2 UDIMMs deployed in programmable logic controllers and factory automation HMIs. IC Role / Device Role / Timing Role: Nonvolatile SPD storage accessed via SMBus during cold start to establish safe default timings before dynamic calibration. Use Value: AT34C02D-SSHM-T's −40 °C to +85 °C rating and 1M endurance ensure reliable operation over extended thermal cycles in industrial enclosures. |
| Embedded DDR Memory Subsystems | Networking Equipment DIMMs |
Use Scenario: Integrating SPD memory into custom DDR-based SoM designs for medical imaging and avionics where qualification traceability is mandatory. IC Role / Device Role / Timing Role: JEDEC-compliant SPD interface ensuring interoperability between FPGA-based memory controllers and third-party DDR modules. Use Value: Permanent software write protection secures SPD header bytes against firmware update errors, preserving module identity and JEDEC compliance. |
Use Scenario: Populating high-density DDR3 LRDIMMs in 5G baseband units requiring robust SPD data integrity under vibration and thermal stress. IC Role / Device Role / Timing Role: SPD EEPROM with hardware write protect (WP = VCC) activated during production test to prevent post-shipment reprogramming. Use Value: Dual protection layers (WP pin + software registers) eliminate risk of field corruption - critical for carrier-grade equipment with multi-year deployment lifecycles. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar SPD EEPROM applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| STMicroelectronics M24C02-RMN6TP | 2 Kbit I²C EEPROM, 1.7–5.5 V, 400 kHz max, SO8 package; lacks JEDEC SPD-specific features (no permanent software write protect, no SPD-compliant default address map). | Requires host firmware adaptation to emulate SPD byte layout; not pre-certified for DDR3 DIMM use. | Select only if SPD compliance is not required and cost optimization is primary; verify full SPD byte mapping in application firmware. |
| ON Semiconductor CAT24C02HU4IGT3 | 2 Kbit I²C EEPROM, 1.7–5.5 V, 400 kHz, SO8; includes write protection via WP pin but no software-based permanent/reversible modes. | Provides basic SPD functionality but cannot lock SPD header bytes permanently - increases risk of accidental overwrite during field updates. | Prefer for general-purpose EEPROM use; avoid where JEDEC SPD header immutability is mandated by system architecture. |
Compared with M24C02-RMN6TP and CAT24C02HU4IGT3, the AT34C02D-SSHM-T uniquely delivers JEDEC EE1002A SPD compliance out-of-box, irreversible header protection, and guaranteed 1 MHz operation at 5 V - making it the only drop-in solution for certified DDR3/DDR2 DIMM manufacturing without firmware or layout modifications.
Availability
AT34C02D-SSHM-T is available at Aetrix Electronics and suitable for DDR3 server memory modules, industrial DDR2 DIMMs, and embedded DDR subsystems requiring stable component supply, long-lifecycle support, and JEDEC SPD compliance.
Supply support for AT34C02D-SSHM-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 maintains full product continuity, quality assurance, and technical documentation for the AT34C02D family.
The AT34C02D series was designed specifically for Serial Presence Detect in DDR/DDR2/DDR3 memory modules, meeting JEDEC EE1002/EE1002A standards with integrated write protection and wide-voltage I²C operation.
FAQ
What is the primary function of the AT34C02D-SSHM-T in a memory module?
The AT34C02D-SSHM-T serves as the Serial Presence Detect (SPD) EEPROM in DDR/DDR2/DDR3 DIMMs, storing standardized configuration data-including module type, speed, timings, and manufacturer information-that the system BIOS reads during power-on initialization. Its JEDEC EE1002A compliance ensures interoperability with memory controllers across server, industrial, and embedded platforms. The AT34C02D-SSHM-T implements this function with hardware and software write protection to safeguard SPD integrity.
Does the AT34C02D-SSHM-T support both 400 kHz and 1 MHz I²C speeds?
Yes, the AT34C02D-SSHM-T supports 400 kHz operation across its full 1.7–3.6 V supply range and 1 MHz operation at 5.0 V. This dual-speed capability aligns with JEDEC SPD timing requirements for DDR1–DDR3 modules, where 400 kHz suffices for most initialization reads, and higher speed enables faster programming during manufacturing. The AT34C02D-SSHM-T's AC characteristics are fully characterized per datasheet Table 5-4 for both conditions.
How does hardware write protection work on the AT34C02D-SSHM-T?
Hardware write protection on the AT34C02D-SSHM-T is controlled by the WP pin: when pulled high to VCC, all write operations-including byte/page writes and software protection register programming-are inhibited, protecting the entire 2 Kbit array. When WP is grounded or floating, software write protection modes become active. This behavior is defined in datasheet Section 4 and Table 4-1, and applies identically to the AT34C02D-SSHM-T regardless of SOIC packaging.
Can the AT34C02D-SSHM-T be used in place of older AT24C02 variants?
No-the AT34C02D-SSHM-T is functionally distinct from generic AT24C02 EEPROMs. While both are 2 Kbit I²C devices, the AT34C02D-SSHM-T implements JEDEC EE1002A SPD-specific features: mandatory SPD address map, permanent/reversible software write protection, and optimized timing for memory controller handshake. Substituting it for an AT24C02 may cause SPD read failures or BIOS incompatibility. The AT34C02D-SSHM-T must be used where SPD compliance is required.
What package type does the AT34C02D-SSHM-T use, and what are its key mechanical dimensions?
The AT34C02D-SSHM-T uses an 8-lead JEDEC-standard SOIC package (package code SS, drawing 8S1), with 0.150" body width, 1.27 mm lead pitch, and RoHS-compliant NiPdAu finish. Its footprint matches industry-standard SOIC-8 footprints, enabling direct placement on DIMM PCBs designed for SPD EEPROMs. Mechanical details-including pin 1 marking, thermal pad absence, and tape-and-reel quantity (4,000 per reel)-are specified in datasheet Section 12 and ordering code AT34C02D-SSHM-T.
AT34C02D-SSHM-T Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- 8-SOIC (0.154", 3.90mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Programmable:
- Verified
- Memory Type:
- Non-Volatile
- Memory Format:
- EEPROM
- Technology:
- EEPROM
- Memory Size:
- 2Kbit
- Memory Organization:
- 256 x 8
- Memory Interface:
- I2C
- Clock Frequency:
- 1 MHz
- Write Cycle Time - Word, Page:
- 5ms
- Access Time:
- -
- Voltage - Supply:
- 1.7V ~ 5.5V
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 8-SOIC
AT34C02D-SSHM-T FAQ
1.How can I place an order for AT34C02D-SSHM-T through Aetrix?
Please submit a Request for Quotation (RFQ) for AT34C02D-SSHM-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 AT34C02D-SSHM-T reliable?
The price and inventory of AT34C02D-SSHM-T are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AT34C02D-SSHM-T is usually 5 days.
3.What payment methods are accepted for AT34C02D-SSHM-T?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AT34C02D-SSHM-T transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AT34C02D-SSHM-T?
AT34C02D-SSHM-T orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AT34C02D-SSHM-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 AT34C02D-SSHM-T?
For technical support, including AT34C02D-SSHM-T datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AT34C02D-SSHM-T requirements.
6.How does Aetrix verify that AT34C02D-SSHM-T is sourced from the original manufacturer or authorized distributors?
All AT34C02D-SSHM-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 AT34C02D-SSHM-T meets industry standards.
7.What is the process for return or replacement of AT34C02D-SSHM-T?
All AT34C02D-SSHM-T units undergo pre-shipment inspection (PSI). If there is an issue with AT34C02D-SSHM-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 AT34C02D-SSHM-T part is unused and in its original packaging.
Return procedure for AT34C02D-SSHM-T:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
AT34C02D-SSHM-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…
