Microchip Technology 93C86C-I/ST

Overview

93C86C-I/ST from Microchip Technology Inc. is a 16 Kbit Microwire-compatible serial EEPROM with programmable 8-/16-bit word organization, write-protect via PE pin, and industrial temperature range (–40°C to +85°C). It features self-timed erase/write cycles, automatic ERAL before WRAL, and 1,000,000 endurance cycles - used in embedded system configuration storage where nonvolatile parameter retention and hardware-level write protection are required.

For engineers reviewing the 93C86C-I/ST datasheet, 93C86C-I/ST pinout, 93C86C-I/ST application, or 93C86C-I/ST equivalent, key selection considerations include VCC range (4.5–5.5 V), ORG/PE pin dependency for memory configuration and write enable, Ready/Busy status polling via DO, and compatibility with Microwire™ serial interface timing at up to 3 MHz.

Technical Context

The 93C86C-I/ST implements a synchronous 3-wire Microwire interface (CS, CLK, DI/DO) with dual-mode memory organization selected by the ORG pin: logic high enables 1024 × 16-bit (x16), logic low enables 2048 × 8-bit (x8). Its internal control logic requires EWEN instruction prior to any erase/write operation, and enforces power-on data protection below 3.8 V VCC threshold.

Write operations are gated by the PE pin - only active when PE = VCC - and include auto-erase before write, ERAL (Erase All), and WRAL (Write All) with dedicated opcodes. Status is reported via DO pin during programming: low = busy, high = ready, with TSV (status valid time) ≤ 500 ns at 4.5–5.5 V.

Key Specifications

Pinout & Package

93C86C-I/ST is packaged in an 8-lead TSSOP (ST package code), with gull-wing leads, 0.65 mm pitch, and Pb-free Matte Tin finish. Pin 1 is marked by laser dot; device orientation follows standard JEDEC TSSOP convention.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 93LC86C-I/ST and 93AA86C-I/ST, the 93C86C-I/ST provides stricter 4.5–5.5 V operation and higher noise immunity in 5 V industrial environments, but sacrifices low-voltage flexibility and ultra-low standby current - making it optimal for legacy 5 V designs with robust power rails.

Availability

93C86C-I/ST is available at Aetrix Electronics and suitable for industrial automation, automotive electronics, and medical instrumentation requiring stable component supply, long-lifecycle support, and RoHS-compliant packaging.

Supply support for 93C86C-I/ST 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 leading provider of microcontroller, analog, and Flash-IP solutions, serving industrial, automotive, and consumer markets with high-reliability silicon and development tools.

The 93C86C belongs to Microchip's legacy 93XX serial EEPROM family, designed specifically for cost-sensitive, space-constrained applications needing simple, robust, and standards-compliant nonvolatile storage with hardware-configurable word width.

FAQ

What is the function of the ORG pin on the 93C86C-I/ST?

The ORG pin on the 93C86C-I/ST selects memory organization: tied to VCC enables 1024 × 16-bit (x16) mode; tied to VSS enables 2048 × 8-bit (x8) mode. This hardware-selectable configuration avoids firmware overhead and ensures deterministic addressing - a feature exclusive to 'C' variants like the 93C86C-I/ST and not present on 'A' or 'B' versions.

How does the PE pin protect against accidental writes in the 93C86C-I/ST?

The PE (Program Enable) pin on the 93C86C-I/ST acts as a hardware write gate: only when PE = VCC can ERASE, WRITE, ERAL, or WRAL instructions execute. If PE = VSS, all programming functions are disabled - even if EWEN is issued. This physical layer protection is mandatory for safety-critical 93C86C-I/ST deployments and differs from software-only lock mechanisms.

What is the minimum VCC required for reliable operation of the 93C86C-I/ST?

The 93C86C-I/ST requires VCC ≥ 4.5 V for guaranteed operation, with a power-on reset (POR) threshold of approximately 3.8 V. Below this voltage, all operations - including reads - are inhibited to prevent data corruption. This 4.5–5.5 V range distinguishes the 93C86C-I/ST from broader-range variants like 93LC86C-I/ST (2.5–5.5 V) and ensures robustness in noisy 5 V industrial rails.

Can the 93C86C-I/ST be used with a 3.3 V microcontroller?

No - the 93C86C-I/ST is specified only for 4.5–5.5 V VCC and requires VIH ≥ 2.0 V (or 0.7×VCC) for reliable logic high recognition. Interfacing directly to a 3.3 V MCU violates its absolute maximum input rating and risks undefined behavior or damage. Use 93LC86C-I/ST or 93AA86C-I/ST instead for true 3.3 V compatibility.

What timing parameter governs the delay between issuing a WRITE command and reading status on the 93C86C-I/ST DO pin?

The status-valid timing parameter TSV (Status Valid Time) governs this delay: ≤ 500 ns after CS goes high (with ≥250 ns CS low time prior), DO reflects Ready/Busy status. For 93C86C-I/ST at 4.5–5.5 V, TSV is guaranteed ≤ 500 ns with CL = 100 pF - enabling rapid polling loops without fixed delays, unlike older EEPROMs requiring ms-scale waits.