Microchip Technology 93AA86/P

Overview

93AA86/P from Microchip Technology Inc. is a 16K-bit (2048 × 8 or 1024 × 16) low-voltage serial EEPROM with Microwire interface, designed for nonvolatile data storage in embedded control and instrumentation systems. It operates down to 1.8V, delivers 1 mA active current and 5 µA standby current at 3.0V, and supports ORG-pin-selectable memory organization. Its self-timed erase/write cycles and integrated power-on/off protection make it suitable for battery-backed sensor logging and configuration storage.

For engineers reviewing the 93AA86/P datasheet, 93AA86/P pinout, 93AA86/P application, or 93AA86/P equivalent, this page provides verified technical context, validated pin functions, confirmed timing parameters across voltage ranges, real-world use scenarios, and two documented alternative parts with explicit functional and application-level differences.

Technical Context

The 93AA86/P implements a synchronous 3-wire Microwire interface (CS/CLK/DI/DO) with programmable x8 or x16 organization selected via the ORG pin. It uses internal self-timed erase/write logic that requires no external timing control - WRAL completes in ≤30 ms and ERAL in ≤15 ms at V_CC ≥ 4.5V. The DO pin serves dual roles: serial data output during READ and Ready/Busy status indicator during programming.

Power management includes automatic write-protection activation on power-up (EWDS state), voltage-based inhibit circuitry below 1.4V, and PE pin hardware lockout. All instructions - including READ (22–29 CLK cycles), WRITE, ERASE, EWEN, and WRAL - are initiated by a Start condition (CS high + DI high on first CLK rising edge), with strict AC timing requirements varying by V_CC range (e.g., F_CLK up to 3 MHz at 4.5–6.0V).

Key Specifications

Pinout & Package

93AA86/P is supplied in an 8-pin PDIP package (300 mil body, JEDEC MS-001). Pin functions are electrically validated per DS21130F and support standard through-hole PCB assembly.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 93AA86/P, the 93AA86C/P offers higher robustness for automotive environments but requires design revalidation, while the AT25160B-PU trades Microwire compatibility and PE pin security for faster SPI throughput and broader vendor support - neither is pin- or functionally identical.

Availability

93AA86/P is available at Aetrix Electronics and suitable for industrial sensor calibration, medical device configuration, and automotive body control modules requiring stable component supply across extended product lifecycles.

Supply support for 93AA86/P 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 Inc. is a U.S.-based semiconductor company specializing in microcontrollers, analog devices, and nonvolatile memory solutions for embedded control applications.

The 93AAxx family was engineered for cost-sensitive, low-power serial EEPROM applications where Microwire compatibility, hardware write protection, and wide voltage operation are essential - particularly in instrumentation and legacy industrial systems.

FAQ

What is the maximum clock frequency supported by the 93AA86/P across its full voltage range?

The 93AA86/P supports up to 3 MHz at V_CC = 4.5–6.0V, 2 MHz at 2.5–4.5V, and 1 MHz at 1.8–2.5V. These limits are defined in Table 1-2 of DS21130F and reflect guaranteed AC timing margins - exceeding them risks command failure or data corruption. The 93AA86/P does not auto-negotiate clock rate; host firmware must configure based on actual V_CC.

How does the ORG pin affect memory addressing and instruction timing in the 93AA86/P?

When ORG = VCC, the 93AA86/P configures as 1024 × 16-bit (11-bit address space); when ORG = VSS, it configures as 2048 × 8-bit (11-bit address space). This changes instruction length: READ requires 29 CLK cycles in x16 mode (vs. 22 in x8), and address fields shift - e.g., ERASE uses A9–A0 in x8 mode but A9–A0 in x16 mode per Tables 1-5 and 1-6. The 93AA86/P's internal decoder routes accordingly.

Can the 93AA86/P be used without connecting the PE pin, and what is the default programming state?

Yes - the 93AA86/P has an internal pull-up on the PE pin, so leaving it unconnected defaults to programming enabled. However, this exposes the memory to accidental writes during noise events or power transients. For production systems, tie PE to VSS to disable writes permanently, or route it to a test point for controlled enablement. The 93AA86/P powers up in EWDS (Erase/Write Disable) state regardless of PE voltage.

What happens to the DO pin during a WRAL operation on the 93AA86/P, and how should it be monitored?

During WRAL, the DO pin outputs Ready/Busy status: low indicates ongoing programming, high signals completion. Monitoring requires holding CS high and polling DO on successive CLK rising edges - DO remains valid until the next Start condition. The 93AA86/P guarantees WRAL completion within 30 ms (typical 16 ms), and DO transitions high only after full array write and internal verification. No external delay is needed beyond TSV (status valid time).

Is the 93AA86/P compatible with modern 3.3V microcontrollers that lack 5V-tolerant inputs?

Yes - the 93AA86/P's VIH1 threshold is 2.0V minimum (for V_CC ≥ 2.7V), and VIH2 is 0.7×V_CC, making it fully compatible with 3.3V logic. Its VOL1 is ≤0.4V at 2.1 mA sink, ensuring solid low-level recognition. However, V_CC must be supplied at the target system voltage (e.g., 3.3V), and the 93AA86/P's own V_CC pin must not exceed 6.0V. The 93AA86/P does not require level shifters for 3.3V hosts.