Microchip Technology AT25020B-MAHL-E

Overview

AT25020B-MAHL-E from Microchip Technology is a 2 Kbit SPI Serial EEPROM (256 × 8) in an 8-lead TSSOP package, operating from 1.8V to 5.5V with industrial temperature range (−40°C to +85°C), 10 MHz max clock at 2.5V, and hardware/software write protection - used for firmware storage, calibration data retention, and configuration backup in embedded controllers.

For engineers reviewing the AT25020B-MAHL-E datasheet, AT25020B-MAHL-E pinout, AT25020B-MAHL-E application, or AT25020B-MAHL-E equivalent, key selection considerations include SPI Mode 0/3 compatibility, 8-byte page write capability, block-level write protection (1/4, 1/2, or full array), HOLD/CS timing coordination, and 1,000,000-cycle endurance with 100-year data retention.

Technical Context

The AT25020B-MAHL-E implements a synchronous SPI slave interface with fixed MSb-first serial protocol, supporting both Mode 0 (SCK idle low) and Mode 3 (SCK idle high); all instructions are 8-bit opcodes followed by address/data bytes aligned to the memory array's 256-word × 8-bit organization.

It integrates on-chip high-voltage generation for EEPROM programming, a STATUS register with nonvolatile BP1/BP0 bits for persistent block protection, and independent HOLD and WP pins enabling concurrent suspend and hardware lock functions without interrupting active write cycles.

Key Specifications

Pinout & Package

AT25020B-MAHL-E is housed in an 8-lead Thin Shrink Small Outline Package (TSSOP) with standard 0.65 mm lead pitch and exposed pad (GND-connected or floating per design).

Key Features

Applications

Equivalent & Alternatives

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

Compared with M95256-DWDW and 25AA020A-I/MS, the AT25020B-MAHL-E provides optimal balance of proven industrial reliability, HOLD-enabled protocol flexibility, and minimal footprint - making it preferred for resource-constrained, safety-critical, or suspend-aware embedded designs where density and ID features are secondary.

Availability

AT25020B-MAHL-E is available at Aetrix Electronics and suitable for industrial sensor calibration, medical device configuration backup, and automotive body control modules requiring stable component supply, long-lifecycle support, and RoHS-compliant sourcing.

Supply support for AT25020B-MAHL-E 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 leading provider of microcontrollers, analog components, and memory solutions, with a focus on embedded control and connectivity.

The AT25020B-MAHL-E belongs to Microchip's AT25xxx family of SPI Serial EEPROMs, engineered for low-power, wide-voltage industrial and automotive applications demanding high endurance and long-term data integrity.

FAQ

What is the maximum SPI clock frequency supported by the AT25020B-MAHL-E at 3.3V operation?

The AT25020B-MAHL-E supports up to 10 MHz SPI clock frequency when VCC is 2.5V to 5.5V, which includes 3.3V operation. This is specified in Table 4-3 of the datasheet under AC Characteristics. The device maintains full timing compliance at this rate, including setup/hold and output valid windows, ensuring robust communication with common 3.3V microcontrollers without additional buffering or clock division.

Does the AT25020B-MAHL-E require external circuitry for power-on reset handling?

No, the AT25020B-MAHL-E includes an internal Power-on Reset (POR) circuit that holds the device in reset until VCC crosses the VPOR threshold (~1.5V) and stabilizes. However, the host system must wait ≥100 µs after VCC stability before issuing the first command. No external RC network is needed, but proper VCC slew rate (≤0.1 V/µs) and CS pull-up (≤10 kΩ) are mandatory per the AT25020B-MAHL-E datasheet to ensure deterministic initialization.

How does the HOLD pin function during an active write cycle in the AT25020B-MAHL-E?

The HOLD pin has no effect on an internal write cycle already in progress in the AT25020B-MAHL-E. It only suspends serial communication (ignores SI/SCK) while preserving the current command state. If a WRITE instruction has been accepted and the self-timed 5 ms write cycle has started, asserting HOLD will pause further command input but will not halt or abort the ongoing EEPROM programming. The device resumes normal SPI operation after HOLD is deasserted and completes the write autonomously.

Can the AT25020B-MAHL-E be used in SPI Mode 3, and what design considerations apply?

Yes, the AT25020B-MAHL-E fully supports SPI Mode 3 (CPOL=1, CPHA=1), where SCK is high when idle. The key design requirement is that the SCK idle state must match before and after each CS assertion/deassertion. The host controller must maintain consistent SCK polarity during CS inactive periods. Mode 3 is functionally identical to Mode 0 in data sampling (rising-edge input, falling-edge output), differing only in idle-state polarity - verified in Section 5.1 of the AT25020B-MAHL-E datasheet.

What happens to the STATUS register's BP1/BP0 bits after power cycling the AT25020B-MAHL-E?

The BP1 and BP0 bits in the STATUS register of the AT25020B-MAHL-E are nonvolatile and retain their last programmed values across power cycles. They are stored in EEPROM cells and persist even when VCC is removed. This allows permanent, hardware-enforced write protection configuration - for example, setting BP1/BP0 = 11 locks the entire array against accidental writes indefinitely until explicitly cleared via WRSR instruction with WP pin high.