Renesas HN58V256AT12E

Overview

HN58V256AT12E from Renesas Electronics is a 256-kbit (32-kword × 8-bit) parallel-interface EEPROM organized with MNOS memory cells and CMOS circuitry, operating from 2.7 V to 5.5 V, featuring 120 ns maximum access time, 10⁵ write/erase cycles in page mode, and 10-year data retention. It serves as nonvolatile program/data storage in microcontroller-based industrial control modules requiring byte- and page-write capability without external high-voltage programming.

For engineers reviewing the HN58V256AT12E datasheet, HN58V256AT12E pinout, HN58V256AT12E application, or HN58V256AT12E equivalent, this device is selected for embedded systems needing reliable, low-power, single-supply EEPROM with software data protection, 64-byte page programming, and JEDEC-compliant byte-wide interface - especially where TSOP-28 packaging and lead-free compliance are required.

Technical Context

The HN58V256AT12E implements a parallel-addressable EEPROM architecture with on-chip address and data latches, enabling direct bus interfacing with microcontrollers and ASICs. Its internal timing logic supports both CE-controlled and WE-controlled write cycles, with automatic page-write initiation after valid address/data setup and 100 µs CE/WE high-to-write transition detection.

It uses MNOS floating-gate technology for nonvolatility and integrates noise immunity circuits that suppress transients ≤20 ns on CE, OE, and WE pins. Unlike the HN58V257A series, it omits RES and RDY/Busy pins - confirming its role as a basic byte/page-programmable EEPROM without hardware reset or status signaling.

Key Specifications

Pinout & Package

HN58V256AT12E uses a 28-pin plastic TSOP (TFP-28DBV) package, 8.0 mm × 13.4 mm × 1.2 mm, lead-free, with gull-wing leads on 0.5 mm pitch.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar EEPROM applications.

Compared with AT28C256-15PU and M95256-DWDW, the HN58V256AT12E delivers faster access, broader voltage range, higher endurance, and true parallel page-write capability - making it optimal for performance-sensitive, mixed-voltage embedded systems requiring minimal firmware overhead and direct MPU interfacing.

Availability

HN58V256AT12E is available at Aetrix Electronics and suitable for industrial control systems, medical instrumentation, automotive body electronics, and point-of-sale terminals requiring stable component supply across extended product lifecycles.

Supply support for HN58V256AT12E 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

Renesas Electronics Corporation is a global semiconductor leader delivering microcontrollers, analog, power, and memory solutions for industrial, automotive, and infrastructure markets.

The HN58V256AT12E belongs to Renesas' legacy parallel EEPROM product line, designed specifically for cost-sensitive, high-reliability embedded systems requiring JEDEC-standard byte-wide nonvolatile storage with robust noise immunity and long-term data integrity.

FAQ

What is the maximum operating temperature range for the HN58V256AT12E?

The HN58V256AT12E is specified for an operating temperature range of 0°C to +70°C, as confirmed in the Recommended DC Operating Conditions table on page 4 of the Rev. 5.00 datasheet. Industrial-grade variants (e.g., HN58V256AT-12I) support −20°C to +85°C, but the HN58V256AT12E itself is rated only for commercial temperature operation. This makes it suitable for indoor, controlled-environment applications such as office equipment and consumer electronics.

Does the HN58V256AT12E support hardware write protection via a dedicated pin?

No, the HN58V256AT12E does not include a RES (reset) pin or hardware write-protection pin. Unlike the HN58V257A series, it relies solely on software data protection (SDP) - a 3-byte unlock sequence (5555h/2AAAh/5555h followed by A0h) - to prevent unintended writes. This is explicitly stated in the Pin Description table (page 3) and Functional Description section (page 16), which note RES and RDY/Busy functions apply "only to the HN58V257A series".

Can the HN58V256AT12E be used with a 3.3 V microcontroller without level shifting?

Yes, the HN58V256AT12E operates natively from 2.7 V to 5.5 V and specifies VIH(min) = 1.9 V at VCC = 3.0 V (page 4), ensuring reliable recognition of 3.3 V logic-high signals. Its I/O pins are CMOS-compatible and tolerate VCC-referenced inputs, allowing direct connection to 3.3 V MCUs such as ARM Cortex-M0+ or Renesas RL78 devices without external level shifters - provided VCC is supplied at 3.3 V and all timing margins are met.

How does data polling work on the HN58V256AT12E without a RDY/Busy pin?

Data polling on the HN58V256AT12E uses I/O7: during an internal write cycle, reading any address returns inverted data on I/O7 until completion, at which point I/O7 stabilizes to the correct value. This is documented in the Data Polling Timing Waveform (page 13) and Functional Description (page 16). Since the HN58V256AT12E lacks RDY/Busy (a feature exclusive to HN58V257A), polling is the primary host-synchronization method - requiring no additional pins or hardware.

Is the HN58V256AT12E RoHS compliant and lead-free?

Yes, the "E" suffix in HN58V256AT12E explicitly denotes lead-free packaging, as confirmed in the Ordering Information table (page 2): "HN58V256AT-12E - 120 ns, 28-pin plastic TSOP (TFP-28DBV), Lead Free". The device complies with RoHS Directive 2011/65/EU and uses matte-tin termination finish, verified in Renesas' material declarations and package dimension notes (page 21).