Microchip Technology AT25512-TH-B

Overview

AT25512-TH-B from Microchip Technology is a 512 Kbit SPI Serial EEPROM (65,536 × 8) in an 8-lead TSSOP package, operating from 1.8V to 5.5V with industrial temperature range (−40°C to +85°C), 20 MHz max clock rate at 5V, and 128-byte page write capability. It serves as nonvolatile configuration and calibration storage in microcontroller-based systems requiring robust data retention and hardware/software write protection.

For engineers reviewing the AT25512-TH-B datasheet, AT25512-TH-B pinout, AT25512-TH-B application, or AT25512-TH-B equivalent, key selection considerations include its dual SPI mode support (0 and 3), 5 ms max self-timed write cycle, 1 M write endurance, 100-year data retention, and integrated WP/HOLD pins for real-time bus control and data integrity assurance.

Technical Context

The AT25512-TH-B implements a synchronous SPI slave interface with fixed MSB-first data framing, rising-edge input sampling on SI, and falling-edge output valid on SO. Its internal architecture includes a high-voltage generation circuit for EEPROM programming, a STATUS register with nonvolatile BP1/BP0 block protection bits, and a Power-on Reset (POR) circuit ensuring stable initialization before instruction acceptance.

It supports hardware write protection via the WP pin (when WPEN=1) and suspend functionality via the HOLD pin-both active only when CS is asserted-and features configurable block protection (1/4, 1/2, or full array) enforced through STATUS register writes, independent of VCC level during operation.

Key Specifications

Pinout & Package

AT25512-TH-B is housed in an 8-lead Thin Shrink Small Outline Package (TSSOP), measuring 4.4 mm × 3.0 mm × 1.2 mm, with gull-wing leads and RoHS-compliant lead finish.

Key Features

Applications

Equivalent & Alternatives

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

Compared with M95512-DRMN6TP/K and BR24G512FJ-WE2, the AT25512-TH-B offers superior SPI throughput scalability across voltage rails, integrated HOLD functionality for deterministic bus pause, and a fully documented, field-proven STATUS register implementation-making it optimal for designs prioritizing timing predictability, real-time control integration, and firmware portability.

Availability

AT25512-TH-B is available at Aetrix Electronics and suitable for industrial PLC configuration storage, medical device calibration data retention, and automotive body control module applications requiring stable component supply, long-lifecycle support, and RoHS-compliant packaging.

Supply support for AT25512-TH-B 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 is a U.S.-based semiconductor manufacturer specializing in microcontrollers, analog devices, and memory solutions, with global design centers and ISO 9001-certified manufacturing.

The AT25512-TH-B belongs to Microchip's AT25xxx family of SPI Serial EEPROMs, engineered for high-reliability, low-voltage embedded systems where data integrity, fast access, and flexible protection mechanisms are essential.

FAQ

What is the maximum SPI clock frequency supported by the AT25512-TH-B at 3.3V operation?

The AT25512-TH-B supports up to 10 MHz SPI clock frequency when VCC is between 2.7V and 5.5V, which includes standard 3.3V operation. This is specified in Table 4-3 of the DS20006218A datasheet under AC Characteristics. The device maintains full timing compliance-including setup/hold and output valid windows-at this rate, enabling efficient bulk reads and writes without requiring clock throttling in 3.3V systems.

Does the AT25512-TH-B require external pull-up resistors on its SPI lines?

The AT25512-TH-B does not require external pull-ups on SI, SO, or SCK, as these are driven actively by the host and device. However, a pull-up resistor (≤10 kΩ) on the CS pin is strongly recommended to ensure it remains high during power-up and prevents spurious selection. The WP and HOLD pins may also benefit from pull-ups depending on system-level noise immunity requirements, though they are internally biased when not driven.

How does the HOLD function behave during an active write cycle in the AT25512-TH-B?

The HOLD function in the AT25512-TH-B has no effect on an ongoing internal write cycle; once initiated, the write completes autonomously in ≤5 ms regardless of HOLD state. HOLD only suspends serial communication-halting further instruction/address/data transfers-and places SO in high-impedance. This allows the host to pause command flow without interrupting EEPROM programming, preserving data integrity during transient bus contention.

Can the AT25512-TH-B be used in a 1.8V-only system without level shifters?

Yes, the AT25512-TH-B is fully specified for 1.8V operation across all electrical characteristics, including DC parameters (VIH/VIL thresholds), AC timing (5 MHz max SCK), and functional behavior (read/write, STATUS register access). Its 1.8V–5.5V supply range eliminates the need for level shifters when interfacing with 1.8V microcontrollers, FPGAs, or ASICs, simplifying board design and reducing component count.

What happens to the STATUS register's WPEN and BP bits after power cycling the AT25512-TH-B?

The WPEN (Write-Protect Enable) and BP1/BP0 (Block Protection) bits in the AT25512-TH-B STATUS register are nonvolatile and retain their last written values across power cycles. They are not reset to factory defaults (WPEN=0, BP1/BP0=00) on power-up. This behavior is explicitly stated in Section 4.6.5 and 4.6.6 of the datasheet, ensuring persistent protection settings without requiring reinitialization firmware overhead.