Skip to main content
Log in
Texas Instruments SN74LS125AN — Memory (DRAM / SRAM / Flash / EEPROM)

SN74LS125AN 74LS Quad Buffer, 3-State, 14-DIP, Active

MPNSN74LS125AN
End of Life

Texas Instruments 74LS series quad buffer, non-inverting, 3-state outputs, 14-DIP (0.300", 7.62mm) through-hole package, 4.75V-5.25V supply, 0°C to 70°C operation.

$0.9Ref. price · indicative, final on quote
Texas Instruments SN74LS125AN datasheet (PDF)
Packaging14-DIP (0.300", 7.62mm)
RoHSROHS3 Compliant
Series74LS
Independent supplier — new & surplus stockAuthenticity-screened · ESD-safe packingListing updated Aug 2026

Specifications

SN74LS125AN specifications
ParameterValue
Series74LS
Logic typeBuffer, Non-Inverting
Output type3-State
MountingThrough Hole
Supply voltage4.75V ~ 5.25V
Current - output high, low2.6mA, 24mA
Operating temperature0°C ~ 70°C (TA)
PackageTube
Case14-DIP (0.300\", 7.62mm)
Number of elements4
Number of bits per element1

Product details

14-pin DIP buffer for bus isolation and signal buffering

The SN74LS125AN packs four independent non-inverting buffers with 3-state outputs in a 14-pin through-hole DIP package (0.300" body width, 7.62 mm pitch). Each buffer drives a single bit, giving you four isolated channels per IC for bus isolation, memory address buffering, or general-purpose signal fan-out on legacy 5 V TTL boards.

Output drive and fan-out for TTL loads

Each output sources 2.6 mA and sinks 24 mA at the rated supply range of 4.75 V to 5.25 V. That sink current drives up to 10 standard TTL loads per output — enough for a buffered address or data bus on a 5 V backplane without external line drivers. The 3-state control lets you float the outputs when the bus is owned by another device.

Frequently asked questions

What is the SN74LS125AN used for?

It is a quad non-inverting buffer with 3-state outputs, used to isolate or drive digital signals on a 5 V bus. Typical applications include memory address buffering, data bus isolation, and general-purpose TTL signal fan-out in through-hole designs.

Can the SN74LS125AN replace the SN74LS645-1N in a circuit?

No — the SN74LS645-1N is an 8-bit transceiver with bidirectional data flow and a different pinout. The SN74LS125AN is a quad buffer with unidirectional, non-inverting outputs. They are not drop-in replacements; a board redesign would be required to swap between them.

What temperature range does the SN74LS125AN support?

It is rated for 0°C to 70°C ambient (commercial grade). This limits deployment to indoor, temperature-controlled environments — not suitable for automotive or industrial extended-temperature enclosures without active cooling.