TS921IPT - 4MHz RRIO High-Output Op Amp | STMicroelectronics
MPN: TS921IPT ✓ ActiveTS921IPT Overview
An operational amplifier is an analog signal-conditioning IC that uses high-gain differential amplification to buffer, amplify, filter, or compare voltage signals. The TS921 belongs to the broader rail-to-rail operational-amplifier category, combining low-noise BiCMOS input and output stages with the ability to swing close to both supply rails. This makes it useful when signals must be processed with minimal rail-to-rail headroom restrictions.
The TS921IPT combines rail-to-rail input and output operation with a 4 MHz gain-bandwidth product and 1 V/us slew rate. Its 9 nV/Hz voltage-noise density supports precision signal-chain work, while its 80 mA output-current capability can drive up to 32 loads according to the manufacturer description. Low distortion, internal ESD protection rated at 1.5 kV, and latch-up immunity improve robustness in practical analog circuits.
The BiCMOS architecture balances low input-noise behavior with high output-drive capability. A gain-bandwidth product of 4 MHz supports signal amplification at moderate frequencies, and the 1 V/us slew rate improves large-signal response compared with slower general-purpose amplifiers. The 8-pin TSSOP-8 package permits compact surface-mount implementation, while rail-to-rail operation reduces the need to keep input and output voltages strictly inside the supply rails.
Typical uses include low-noise sensor conditioning, audio signal paths, current sensing, active filtering, instrumentation, and general-purpose buffering. The 80 mA output capability is particularly relevant when the amplifier must drive a relatively heavy capacitive or resistive load. Designers should still check load stability and output-current limits for the complete application rather than relying on peak capability alone.
Decoupling should be placed close to the supply pins, and sensitive input routing should avoid proximity to switching nodes and high-current return paths. The amplifier must operate within its specified common-mode and supply-voltage limits. Because the available package drawing could not be independently verified against a pin-description table, use the manufacturer datasheet before assigning PCB tracks or making pin-sensitive substitutions.
This page combines the verified TS921IPT operating characteristics with practical application guidance, sourcing instructions, and a focused drop-in assessment. The alternative list intentionally excludes unverified cross-package or speculative equivalents so that engineers can distinguish a genuine TSSOP-8 replacement from a merely similar amplifier.
Drop-in alternatives for TS921IPT — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
TS921IJT
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
TS921IPT Maximum Ratings & Electrical Characteristics
| Amplifier Type | Single operational amplifier |
| Architecture | BiCMOS |
| Input Rail-to-Rail | Rail-to-rail |
| Output Rail-to-Rail | Rail-to-rail |
| Gain-Bandwidth Product | 4 MHz |
| Slew Rate | 1 V/us |
| Voltage Noise Density | 9 nV/Hz |
| High Output Current | 80 mA |
| Output Drive Capacity | Up to 32 loads |
| Optimized Supply Voltage | 3 V and 5 V |
| Maximum Stated Operating Supply Voltage | 12 V |
| Internal ESD Protection | 1.5 kV |
| Distortion | Low distortion |
| Latch-Up Immunity | Supported |
| Number of Circuits | 1 circuit |
| Package | 8-pin TSSOP |
| Mounting Type | Surface mount |
| Macromodel | Included in the device specification |
TS921IPT 8-pin tssop Pin Configuration Guide
Pin configuration for TS921IPT (8-pin tssop package). This analog component features input, output, and power supply pins. Refer to the manufacturer datasheet for offset null, compensation, and enable pin configurations. Ideal for signal conditioning and amplifier circuits.
No detailed pinout data available for TS921IPT.
Refer to the datasheet for full pin configuration.
Typical Applications
TS921IPT is suitable for 6 applications: Low-Noise Sensor Signal Conditioning, Audio Signal Buffering, Active Filtering and Signal Shaping, Industrial Control and Instrumentation, Current-Sense Amplification, Portable and Battery-Powered Electronics.
Low-Noise Sensor Signal Conditioning
The TS921IPT fits sensor-conditioning stages that require modest signal gain, rail-to-rail input acceptance, and low added noise. Its 9 nV/Hz voltage-noise density and 4 MHz gain-bandwidth product support amplification of sensor outputs while preserving useful bandwidth. The rail-to-rail input stage also reduces headroom concerns when the sensor output approaches either supply rail. Place the amplifier close to the sensor or connector, use short guarded input traces, and confirm common-mode behavior across the complete signal range before fixing the gain.
Recommended
Audio Signal Buffering
The TS921IPT can buffer a low-level audio or instrumentation signal where rail-to-rail operation and moderate drive current are important. Its low-distortion characteristic supports faithful amplification, while 9 nV/Hz noise density is suitable for many general audio and measurement paths. The 80 mA output-current rating provides additional drive margin for higher-impedance next stages. Keep the feedback loop compact, maintain stable gain with the selected load, and place input and output decoupling according to the manufacturer application guidance.
Recommended
Active Filtering and Signal Shaping
The TS921IPT is suitable for active low-pass, high-pass, and other analog filtering stages operating at moderate frequencies. Its 4 MHz gain-bandwidth product provides usable closed-loop bandwidth for many low-to-medium-frequency filters, and the 1 V/us slew rate helps preserve large-signal response. Rail-to-rail input and output operation increases usable input and output range in single-supply systems. Select component values against the closed-loop bandwidth and noise-gain curve, and verify capacitive-load stability when driving long cables or downstream sampling devices.
Recommended
Industrial Control and Instrumentation
The TS921IPT can amplify and buffer control or instrumentation signals in equipment operating from 3 V, 5 V, or up to the stated 12 V operating condition. Rail-to-rail behavior is useful when a controller must monitor a signal near a supply rail, while the high output-current capability allows the amplifier to drive a moderate load. The design must still account for supply noise, grounding, temperature limits, and the amplifier's behavior at the actual supply voltage. Use a stable reference and protection network where long sensor cables are connected.
Recommended
Current-Sense Amplification
The TS921IPT can provide input amplification and buffering around a low-value current-sense element when the signal bandwidth is compatible with a 4 MHz gain-bandwidth product. Rail-to-rail input operation increases the usable common-mode span in compact power systems, and the 80 mA output rating helps when driving an ADC input network or measurement stage. Accurate sensing still depends on the shunt value, amplifier offset and bias behavior, Kelvin routing, and reference accuracy. Verify gain error across temperature before using it for precision measurements.
Recommended
Portable and Battery-Powered Electronics
The TS921IPT is appropriate for compact battery-powered circuits that operate from 3 V or 5 V and require rail-to-rail signal handling. Its small TSSOP-8 package supports space-constrained layouts, and its 4 MHz bandwidth is sufficient for many control, sensing, and audio tasks. The BiCMOS implementation provides low-noise operation, while the 80 mA output capability can reduce the need for an additional buffer in moderate-load designs. Check quiescent-current limits and output-current behavior at the minimum battery voltage before assigning the part to a low-power product.
Recommended
Engineering reference data for TS921IPT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | TS921IJT |
|---|---|---|
| Brand | STMicroelectronics | STMicroelectronics |
| Package | 8-pin TSSOP | 8-pin TSSOP |
| Amplifier Configuration | Single | Single |
| Architecture | BiCMOS | BiCMOS |
| Gain-Bandwidth Product | 4 MHz | 4 MHz |
| Slew Rate | 1 V/us | 1 V/us |
| Voltage Noise Density | 9 nV/Hz | 9 nV/Hz |
| Output Current | 80 mA | 80 mA |
| Input and Output Operation | Rail-to-rail | Rail-to-rail |
| Optimized Supply Voltage | 3 V and 5 V | 3 V and 5 V |
Key Differentiators
- High output-drive capability within an 8-pin TSSOP amplifier (vs TS921IJT)
- Low-noise rail-to-rail operation for signal conditioning (vs TS921IJT)
- Optimized single-supply operation with rail-to-rail I/O (vs TS921IJT)
Design Notes
Use the manufacturer package drawing and pin-description table before routing the TSSOP-8 footprint. Place the input, feedback, and bypass components close to their associated pins, and keep the high-impedance input node away from switching nodes and inductor-current paths. A short ground return from the device to the system reference plane helps reduce output-induced feedback. Verify the land pattern against the exact terminal dimensions rather than relying on a generic TSSOP footprint.
The TS921IPT is optimized for 3 V and 5 V operation and is described as operating from 12 V. Check the manufacturer electrical-characteristics table for headroom, quiescent current, output swing, and thermal limits at the actual rail voltage. Do not infer 3 V or 5 V noise, bandwidth, and common-mode performance from the headline values without consulting the corresponding test conditions. Add local supply bypassing and control ground-current return paths to avoid converting supply ripple into output noise.
Do not treat the 80 mA output-current capability as permission to operate continuously at that level. Assess the worst-case load, capacitive drive, duty cycle, ambient temperature, and copper available for heat dissipation. The 4 MHz gain-bandwidth product also means that noise gain and feedback topology determine the usable closed-loop bandwidth. Validate stability with the intended load and consider the output-current behavior of TS921IJT if evaluating it as a replacement.
Compliance Information
The indexed product information confirms RoHS and REACH wording in the TS921 description but does not state a compliance declaration. The device is not presented as an AEC-Q100-qualified automotive part.