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SN74HC646DWR

SN74HC646DWR 74HC Transceiver, Non-Inverting, 3-State, 2V-6V

MPNSN74HC646DWR
End of Life

Texas Instruments 74HC series SN74HC646DWR, 8-bit transceiver, non-inverting, 3-state outputs, 2V to 6V supply, 7.8mA output current, -40°C to 85°C, 24-SOIC package.

$1.68Ref. price · indicative, final on quote
Packaging24-SOIC (0.295", 7.50mm Width)
RoHSROHS3 Compliant
Series74HC
Independent supplier — new & surplus stockAuthenticity-screened · ESD-safe packingListing updated Aug 2026

Specifications

SN74HC646DWR specifications
ParameterValue
Series74HC
Logic typeTransceiver, Non-Inverting
Output type3-State
MountingSurface Mount
Supply voltage2V ~ 6V
Current - output high, low7.8mA, 7.8mA
Operating temperature-40°C ~ 85°C (TA)
PackageTape & Reel (TR); Cut Tape (CT)
Case24-SOIC (0.295\", 7.50mm Width)
Number of elements1
Number of bits per element8

Product details

7.8 mA output drive — fan-out and load budget

Each output sinks or sources 7.8 mA, enough to drive a handful of HC-family inputs or a single TTL load, but not enough for a heavily loaded backplane or a bank of LEDs without a buffer. For bus-oriented designs, the 3-state outputs let multiple devices share the same data lines without contention, as long as the enable timing is managed.

The 24-SOIC (7.50 mm width) footprint is a standard body size, so board layout is straightforward and second-sourcing to another 74HC 24-SOIC transceiver is possible if supply tightens.

Frequently asked questions

Is SN74HC646DWR RoHS compliant?

Yes, the SN74HC646DWR is ROHS3 compliant, meaning it meets the RoHS directive's substance restrictions including lead, mercury, and cadmium.

How does SN74HC646DWR compare to SN74HC245?

Both are 8-bit transceivers from the 74HC family with 3-state outputs and the same 2V to 6V supply range. The SN74HC646DWR includes a storage register on each port (D-type flip-flops with enable), so it can latch data independently of the bus state, whereas the SN74HC245 is a simple transparent transceiver without registers. Choose the SN74HC646DWR when you need to hold data through bus turnover or pipeline a transfer.