Product Overview
AT&T T7220PC Integrated Circuit - 28-Pin Plastic DIP, Clean and Legible
Condition
Used, clean, and in excellent cosmetic condition. The photographs show a matte black 28-pin plastic dual inline package with the top marking still sharp and fully legible: a circled M mark beside the AT&T name, then T 7220 PC, then 08391TS 74 on the third line. The pin 1 notch is intact at one end of the body. All 28 leads are present, straight, and evenly spaced, with bright tin plating and no bent, clipped, or corroded pins visible. No cracks, chips, scuffs, or ink loss on the body. Against the PartsMine millimeter ruler the body runs from just before the zero mark to just short of 40 mm. This chip has not been powered up or functionally tested here, and its internal function is not confirmed.
Same or next business day shipping from our Idaho warehouse. Honest pricing, no nonsense.
Online since 1999. We are here for our customers, with a no-hassle satisfaction guarantee.
Product Overview
This is an AT&T T7220PC integrated circuit supplied in a 28-pin plastic DIP, the through-hole package that dominated board-level design before surface mount took over. The part came out of what appeared to be a legacy ethernet device, and the earlier listing described it as potentially suited to legacy 10-base ethernet hardware. We are repeating that as the hedge it is: the specific function, pinout, and electrical ratings of the T7220PC are not confirmed here, so treat the printed markings as the identity and the datasheet as the authority. What is confirmed is what the camera shows: the AT&T name and circled M mark, the T 7220 PC part line, and the 08391TS 74 code line underneath, all crisp on a clean body with straight, bright leads. Four pieces are in stock. One of them is the unit photographed here; the other three were not individually photographed, so the images stand as representative of the group rather than a per-unit condition record.
Key Features
- Part number: AT&T T7220PC
- Package: 28-pin plastic dual inline package (DIP-28), through-hole
- Top marking, line 1: circled M mark with AT&T
- Top marking, line 2: T 7220 PC
- Top marking, line 3: 08391TS 74
- Pin 1 notch present at one end of the body
- Leads: all 28 present, straight and unclipped, bright tin plating
- Condition: Used, clean, no visible defects
- Function, pinout, and electrical ratings: not confirmed - verify against the AT&T datasheet before use
- Application: previously described as potentially suited to legacy 10-base ethernet devices, not confirmed
Applications
- A repair technician working a legacy 10-base ethernet card whose silkscreen or bill of materials calls out a T7220 and who needs a physical match to compare against the board
- A retrocomputing restorer sourcing obsolete AT&T silicon that has long since fallen out of normal distribution channels
- A bench engineer who wants a socketed spare on hand before pulling a working chip out of a donor board
- A collector or archivist documenting AT&T-marked integrated circuits and wanting a clean, photographable example with sharp, legible top markings
Frequently Asked Questions
What exactly is printed on the top of the chip?
Three lines. A circled M mark next to AT&T on the first line, T 7220 PC on the second, and 08391TS 74 on the third. All three are legible in the close-up photo, which is the second image. We have not decoded the 08391TS 74 line, so read it as the manufacturer marking it is rather than a confirmed date code.
Has this chip been tested?
No. It has been visually inspected only. It has not been powered up, socketed, or checked against a known-good board, and we have not confirmed its function, pinout, or supply requirements. If your repair depends on the part working, plan to verify it yourself.
Will it drop into a standard 28-pin socket?
The photos show a 28-pin plastic DIP with every lead present, straight, and unclipped, which is what a socket needs. Row spacing is not confirmed here, so compare the photos against your socket or board footprint before you order.
Is this really a networking part?
Not confirmed. The chip was recovered from what appeared to be a legacy ethernet device, and that is the honest limit of what we know about its history. The part number on the package is the reliable thread to pull; anything beyond it should come from an AT&T datasheet, not from us.
It is used and untested - what am I actually taking on?
You are getting an AT&T T7220PC in a 28-pin plastic DIP like the one photographed here, which had legible markings, all 28 leads straight, and no visible damage. Four are in stock and only one was photographed, so read the images as representative of the group rather than as a record of the individual chip that ships to you. What you are absorbing is the electrical unknown. It has not been powered up here, its function and pinout are not confirmed, and there is no way for us to promise it works in your circuit, so the photographs and the printed markings are the spec you are buying against. That is the trade for an obsolete AT&T chip you can actually see before it ships. Shipping is $8 flat rate and free once your order passes $28, and orders leave our Idaho warehouse the same or next business day.
A matte black DIP with the AT&T name still crisp on top, from the years when the phone company built its own silicon. What it did inside that network box is a datasheet question, and the answer is yours to chase.
