Single op-amp with rail-to-rail input and output on a single 2.5 to 5.5 V supply, offering 5.5 MHz of bandwidth with low distortion in a SOT-23-5. It swings to within millivolts of both rails and drives ADC inputs and light loads cleanly, which suits it to single-supply data-acquisition front ends and audio buffering on 3.3 and 5 V boards. A general-purpose rail-to-rail single with more bandwidth than the low-cost commodity parts, the single of the OPA340/2340/4340 family.

Pinout

Pin	Name	Type	Function
1	OUT	output	Amplifier output. Rail-to-rail output stage swings within 1 mV of either supply rail with a 100-kOhm load. Short-circuit protected to ground (one amplifier per package).
2	V-	power_in	Negative (lowest) power supply. Tie to GND for single-supply operation or to a negative rail for dual-supply operation. Total supply span (V+) - (V-) must not exceed 5.5 V.
3	+IN	input	Positive (noninverting) input. Rail-to-rail input common-mode voltage range extends 500 mV below V- and 500 mV above V+. Input signals swinging more than 0.5 V beyond the rails should be current-limited to <=10 mA (diode-clamped to supplies).
4	-IN	input	Negative (inverting) input. Rail-to-rail input common-mode voltage range extends 500 mV below V- and 500 mV above V+. Diode-clamped to supplies; limit signal current beyond rails to <=10 mA.
5	V+	power_in	Positive (highest) power supply. Operating range 2.7 V to 5.5 V (single supply) with (V+) - (V-) not exceeding 5.5 V. Bypass with 0.1 uF ceramic to V-/GND close to the pin.

Key specifications

Parameter	Value
Type	Single rail-to-rail op-amp
Gain-bandwidth	5.5 MHz
Supply	2.5-5.5 V (single)
Output	Rail-to-rail
Slew rate	6 V/us
Input offset	150 uV (typ)
Package	SOT-23-5

Ordering variants

Same part, different packaging or reel option.

OPA340NA (SOT-23-5)
OPA340UA (SOIC-8)
OPA2340UA (dual, SOIC-8)

CAD (KiCad official)

Symbol: Amplifier_Operational:OPA340NA (KiCad official)
Footprint: Package_TO_SOT_SMD:SOT-23-5
3D model: SOT-23-5 (KiCad packages3D, STEP)

Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

Datasheet: Texas Instruments datasheet (48 pp, sha256 8099f9f9e8e49c45, retrieved 2026-08-17, tier: manufacturer)
Extractor: ds2sf (Claude). Every pin and dimension is cited to a datasheet page; it refuses to fabricate.
CAD: KiCad official libraries (CC-BY-SA 4.0).

Datasheet PDF