TS921ID - 4MHz High-Output RRIO Op Amp | STMicroelectronics
N.º de pieza: TS921ID ✓ ActivoTS921ID Descripción general
An operational amplifier is a voltage-controlled differential amplifier that uses high open-loop gain to amplify small input signals. The TS921 belongs to the rail-to-rail input/output, or RRIO, family, allowing its input common-mode range and output swing to approach the supply rails. This makes it useful for low-voltage battery-powered equipment, sensor interfaces, audio stages, industrial controls, and portable instruments where the signal can occupy much of the available supply range.
The TS921's principal features include low input noise of 9 nV/sqrt(Hz), a 4 MHz gain-bandwidth product, 1.3 V/us slew rate, and an output stage capable of delivering 80 mA. The manufacturer identifies the device as optimized and fully specified for 3 V and 5 V supplies, while verified distributor data also gives a 2.7 V to 12 V operating-voltage range. Rail-to-rail operation reduces the need for separate positive and negative supply rails in single-supply designs.
The BiCMOS process combines bipolar input characteristics with CMOS output circuitry. In practical signal chains, the TS921 can condition low-level sensor outputs, buffer precision ADC inputs, or provide general-purpose gain. Its 80 mA output capability is useful for driving moderate loads, although sustained heavy loading can reduce output swing and increase power dissipation. The 4 MHz bandwidth supports applications requiring moderate rather than high-frequency closed-loop performance.
Typical uses include battery-operated instrumentation, low-voltage audio, industrial sensor conditioning, active filters, and portable measurement equipment. The SOIC-8 format supports conventional surface-mount assembly, while the manufacturer datasheet provides the authoritative pin connection and recommended application information for layout and decoupling decisions.
For single-supply operation, reserve output headroom for the load and check the input common-mode range across the complete signal excursion. Place the supply bypass capacitor close to the positive and ground pins, and use short, low-impedance feedback routes to limit parasitic feedback and preserve stability.
This product page combines the verified manufacturer and distributor information with package, application, comparison, and design guidance. It identifies where TS921ID fits, highlights the 4 MHz bandwidth and 80 mA output-current capabilities, and clearly separates confirmed data from engineering details that require additional verification.
Alternativas directas para TS921ID — mismo encapsulado, compatible pin a pin. Se excluyen las piezas de otro encapsulado que requieren retrabajo de la PCB.
Variantes de esta serie
Modelos de la misma serie compatibles directamente con TS921ID (mismo factor de forma y huella) — difiere en Amplifier Type, Package, Gain-Bandwidth Product, Supply Voltage Range, Input Offset Voltage.
TS922ID
✅ Sustitución directaConsulte el precio
Ver hoja de datos →TS925ID
✅ Sustitución directaConsulte el precio
Ver hoja de datos →TS912ID
✅ Sustitución directa ⚠️ Especificaciones sin verificarConsulte el precio
Ver hoja de datos →TS902ID
✅ Sustitución directa ⚠️ Especificaciones sin verificarConsulte el precio
Ver hoja de datos →TS921IYD
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
TS921ID Valores máximos y características eléctricas
| Amplifier Type | Single operational amplifier |
| Process Technology | BiCMOS |
| Operating Supply Range | 2.7 V to 12 V |
| Optimized Supply Voltage | 3 V and 5 V |
| Gain-Bandwidth Product | 4 MHz |
| Slew Rate | 1.3 V/us |
| Input Noise Density | 9 nV/sqrt(Hz) |
| Corriente de salida máxima | 80 mA |
| Input Common-Mode Range | Rail-to-rail |
| Output Swing | Rail-to-rail |
| Number of Amplifiers | 1 |
| Número de pines | 8 |
| Encapsulado | 8-pin SOIC |
| Tipo de montaje | Surface mount |
| Output Current Capability | 80 mA; able to drive 32 loads |
| Internal Protection | ESD internal protection |
| Estado RoHS | unknown |
| REACH Status | unknown |
| AEC-Q100 Qualification | not_applicable |
Configuración de pines de TS921ID
| Pin 1 | NC — Not connected |
| Pin 2 | IN- — Inverting input |
| Pin 3 | IN+ — Non-inverting input |
| Pin 4 | V- — Negative supply or ground |
| Pin 5 | NC — Not connected |
| Pin 6 | OUT — Output |
| Pin 7 | V+ — Positive supply |
| Pin 8 | NC — Not connected |
Aplicaciones típicas
TS921ID es adecuado para 6 aplicacións: Battery-Powered Sensor Conditioning, Portable Audio Signal Chain, Active Filtering and Control Loops, Industrial Instrumentation Buffer, ADC and DAC Output Buffering, Portable Test and Measurement.
Battery-Powered Sensor Conditioning
The TS921ID suits low-voltage sensor front ends because its rail-to-rail input stage can accept signals near the supply rails, while the 9 nV/sqrt(Hz) input-noise density supports low-level measurements. With a 2.7 V to 12 V operating range and specifications optimized for 3 V and 5 V systems, it can amplify outputs from resistive, bridge, or level sensors without requiring a second negative supply. Place the device close to the sensor return, use short signal traces, and bypass the supply locally. The 4 MHz bandwidth provides ample margin for moderate-bandwidth sensing, although the selected gain must remain stable with the sensor's output capacitance.
Recomendado
Portable Audio Signal Chain
The TS921ID is appropriate for portable single-supply audio stages requiring rail-to-rail input and output swing. Its 80 mA output-current capability can support moderate loads, and the 1.3 V/us slew rate helps preserve large-signal response through small audio buffers. The 9 nV/sqrt(Hz) input-noise density is favorable for microphone and line-level preamplification when combined with suitable gain. Designers should still calculate output swing into the selected load and avoid assuming that the 80 mA rating allows continuous high-current operation. Decouple the supply close to pin 7 and keep the audio return path away from switching and digital return currents.
Recomendado
Active Filtering and Control Loops
The TS921ID's 4 MHz gain-bandwidth product and 1.3 V/us slew rate make it useful for active filters, integrators, and low-frequency control loops operating from 3 V or 5 V. These functions benefit from a wide closed-loop bandwidth that is generally above the signal bandwidth while still supporting stable operation at the selected noise gain. The rail-to-rail input range helps preserve signal amplitude near the lower and upper supply limits. Component tolerances in the feedback network determine filter accuracy, so use stable resistors and capacitors. Validate phase margin and transient behavior with the final source and load impedances rather than relying on gain-bandwidth alone.
Recomendado
Industrial Instrumentation Buffer
The TS921ID can buffer sensor outputs in compact industrial measurement equipment that operates from a 3 V or 5 V rail. Its rail-to-rail input and output behavior reduces signal-headroom loss, while low-voltage operation complements portable test instruments. The 80 mA output capability is sufficient for moderate analog stages, and the 4 MHz bandwidth is much higher than required by many slowly changing process signals. For long cable connections, protect the input against excessive differential voltage and ESD, and confirm that the selected gain remains stable with distributed input capacitance. A local bypass capacitor and quiet grounding layout are essential when the amplifier follows a resistive sensor.
Recomendado
ADC and DAC Output Buffering
The TS921ID is useful as an analog buffer between converters and downstream circuitry because its rail-to-rail output can operate close to the available supply limits. The 4 MHz bandwidth and 1.3 V/us slew rate provide ample response for many medium- and high-resolution conversion systems, while the 80 mA output capability can drive moderate sampling and hold circuitry. When driving successive-approximation ADCs, the settling requirements should be calculated with the actual output impedance, sample-and-hold capacitance, and acquisition time. Keep the buffer physically close to the converter to minimize capacitive loading and trace noise.
Recomendado
Portable Test and Measurement
The TS921ID fits low-voltage handheld or bench measurement products requiring a general-purpose amplifier with broad input range and modest drive capability. Its 2.7 V to 12 V supply range covers 3 V and 5 V systems, while the 9 nV/sqrt(Hz) input-noise density supports precision probing stages. Rail-to-rail inputs are useful when measurements approach either supply rail, and the 4 MHz bandwidth supports calibration and signal-tracing tasks. Use a low-noise reference supply, separate analog and return-current paths, and verify input overdrive behavior for test fixtures that can present abrupt voltage steps. The final instrument accuracy should not depend on the amplifier alone; resistor networks and reference components also require suitable tolerances and stability.
Recomendado
Resumen de productos recomendados
Datos de referencia de ingeniería para TS921ID — comparación, orientación de diseño e información de cumplimiento.
Guía de selección
Comparación con alternativas
| Parámetro | Este producto | TS922ID | TS925ID | TS912ID | TS902ID | TS921IYD |
|---|---|---|---|---|---|---|
| Package | 8-pin SOIC | 8-pin SOIC | 8-pin SOIC | 8-pin SOIC | 8-pin SOIC | 8-pin SOIC |
| Brand | STMicroelectronics | STMicroelectronics | STMicroelectronics | STMicroelectronics | STMicroelectronics | STMicroelectronics |
| Amplifier Count | 1 | 1 | 1 | 1 | 1 | 1 |
Diferenciadores clave
- Documented high-output-current operation (frente a TS921IYD)
- Explicit optimization for common low-voltage rails (frente a TS922ID)
- Documented noise and speed combination (frente a TS925ID)
Notas de diseño
Do not treat the TS921ID as a universal pin-compatible replacement for every 8-pin single op amp. Verify the manufacturer's pin diagram before changing the PCB, particularly for device families that assign different pins to IN+, IN-, OUT, and supply rails. Rail-to-rail input does not remove input common-mode restrictions caused by supply voltage, while the usable output swing still depends on output current and load. Review the TS921 manufacturer datasheet before fixing gain, filter poles, or ADC drive requirements.
Place the supply-bypass capacitor physically close to the positive supply and ground pins, with a short and low-impedance return path. Keep the feedback components close to the amplifier pins so that parasitic capacitance in the feedback node does not alter stability or distort the intended noise gain. For sensor or ADC interfaces, route the input away from switching-node copper and digital return currents. The 4 MHz gain-bandwidth product is sufficient for many moderate-bandwidth circuits, but good layout remains necessary to realize the expected noise and transient performance.
The TS921ID is optimized for 3 V and 5 V operation and is verified as operating from 2.7 V to 12 V. At low supply voltages, verify both input headroom and output swing at the maximum load because rail-to-rail descriptions do not guarantee zero headroom under all conditions. The 80 mA output-current capability is a device rating, not a recommended continuous operating point. If driving a low-impedance load, calculate output dissipation, check the manufacturer thermal limits, and provide adequate copper area or other heat spreading as required.
Información de cumplimiento
The supplied verified data does not explicitly state RoHS, REACH, lead-free, halogen-free, or conflict-minerals compliance. TS921ID is an operational amplifier and is not an automotive-qualified AEC-Q100 device in the provided information.