TS944ID - 4-Channel 10kHz Micropower Op Amp | STMicroelectronics
MPN: TS944ID ✓ ActiveTS944ID Overview
An operational amplifier is an analog integrated circuit that amplifies the voltage difference between its inverting and non-inverting inputs. The TS944ID belongs to the micropower operational-amplifier family within the broader linear-amplifier and signal-conditioning hierarchy. Rail-to-rail output allows the amplifier to approach its supply limits more closely than fixed-output amplifiers, improving output swing in low-voltage systems where signal headroom is limited.
The principal benefits of the TS944ID are integration, low power consumption, and rail-to-rail operation. Four amplifiers in one 14-pin SOIC reduce component count and board area compared with four separate single or dual amplifier packages. The 10 kHz gain-bandwidth product is suitable for low-frequency signal conditioning, including sensor buffers, transducer amplification, and general feedback-control networks. Its approximately 1.2 uA supply current is especially useful in battery-powered instrumentation where continuous analog circuitry must consume little power.
The TS944ID is designed for general-purpose analog applications rather than high-speed signal processing. Its modest 10 kHz gain-bandwidth product favors slowly changing signals, such as sensor outputs, voltage references, and control-loop error amplifiers. The 2.5 V to 10 V operating range supports low-voltage battery systems, portable instruments, industrial monitoring circuits, and embedded control platforms. The -40°C to +85°C range covers industrial and commercial environments where extended automotive qualification is not required.
Typical uses include four-channel sensor acquisition, portable measurement systems, low-frequency active filters, analog signal conditioning, and embedded control interfaces. Using one quad device for similar low-frequency channels can simplify routing and reduce package count. However, all four channels share common supply pins, so they cannot use independent positive and negative supply voltages. Input common-mode and output-swing behavior should also be checked against the actual signal range.
When laying out a TS944ID board, place each bypass capacitor close to the device supply pins and keep feedback components near their associated amplifier inputs and outputs. Use short, quiet input paths for sensor signals and provide adequate return paths to minimize ground coupling. Avoid using this micropower amplifier where wide bandwidth, high output-current capability, or precision offset and drift specifications are essential; a higher-bandwidth or more accurate amplifier family will usually provide a better margin.
This page combines the verified TS944ID ordering information, package and electrical characteristics, application guidance, pinout, and strict same-footprint replacement analysis. It also identifies where alternative data is unavailable, helping engineers distinguish confirmed device facts from options requiring a separate qualification review.
Drop-in alternatives for TS944ID — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with TS944ID (same form factor and footprint) — differing in Number of Pins, Package.
No drop-in alternatives available for this product.
Request AlternativesTS944ID Maximum Ratings & Electrical Characteristics
| Amplifier Type | General-purpose operational amplifier |
| Number of Channels | 4 circuits |
| Output Type | Rail-to-rail |
| Gain-Bandwidth Product | 10 kHz |
| Supply Current | 1.2 uA |
| Operating Supply Voltage Range | 2.5 V to 10 V |
| Operating Temperature Range | -40°C to +85°C |
| Package | 14-SOIC (0.154 inch, 3.90 mm width) |
| Mounting Type | Surface mount |
| Number of Pins | 14 pins |
TS944ID Pin Configuration
| Pin 1 | OUT1 — Output of amplifier 1 |
| Pin 2 | -IN1 — Inverting input of amplifier 1 |
| Pin 3 | +IN1 — Non-inverting input of amplifier 1 |
| Pin 4 | V- — Negative supply connection |
| Pin 5 | +IN2 — Non-inverting input of amplifier 2 |
| Pin 6 | -IN2 — Inverting input of amplifier 2 |
| Pin 7 | OUT2 — Output of amplifier 2 |
| Pin 8 | OUT3 — Output of amplifier 3 |
| Pin 9 | -IN3 — Inverting input of amplifier 3 |
| Pin 10 | +IN3 — Non-inverting input of amplifier 3 |
| Pin 11 | V+ — Positive supply connection |
| Pin 12 | +IN4 — Non-inverting input of amplifier 4 |
| Pin 13 | -IN4 — Inverting input of amplifier 4 |
| Pin 14 | OUT4 — Output of amplifier 4 |
Typical Applications
TS944ID is suitable for 6 applications: Battery-Powered Sensor Conditioning, Portable Measurement Instruments, Industrial Process Monitoring, Low-Frequency Active Filters, Embedded Control Analog Front Ends, Precision Voltage and Current Buffering.
Battery-Powered Sensor Conditioning
The TS944ID suits battery-powered sensor interfaces that require several low-frequency amplification stages without consuming substantial supply current. Its approximately 1.2 uA supply current and 2.5 V minimum operating voltage are valuable for portable measurement systems powered from small cells or energy-harvesting sources. Four rail-to-rail output channels can buffer inputs from resistive, resistive-divider, or slowly changing sensor networks. Because the 10 kHz gain-bandwidth product is modest, the device should serve low-frequency sensor signals rather than waveforms with sharp transitions. Check each sensor's voltage range against the input common-mode limits, and place the bypass capacitor close to the common supply pins.
Recommended
Portable Measurement Instruments
The TS944ID is appropriate for compact, battery-operated instruments in which several analog channels must share limited board area. Four amplifiers in one 14-SOIC can support source buffering, gain stages, and differential active filters for slow process measurements. The 2.5 V to 10 V supply range allows operation from low-energy rails, while approximately 1.2 uA supply current helps limit continuous drain. Rail-to-rail operation can preserve signal swing in low-voltage designs. The 10 kHz gain-bandwidth product restricts use to low-frequency measurements, so high-bandwidth sensors, transient capture, or audio signals would require a faster amplifier with greater supply-current capability.
Recommended
Industrial Process Monitoring
The TS944ID can condition several low-rate process signals within industrial monitoring equipment when the -40°C to +85°C operating range is adequate. Typical channels include buffered pressure, temperature, level, or potentiometer inputs that change slowly relative to the amplifier's 10 kHz gain-bandwidth product. Rail-to-rail outputs help maximize usable range from a 2.5 V to 10 V system supply, and the quad configuration reduces the number of analog packages on the board. Confirm the measured input range, offset accuracy, and common-mode limits at the worst supply voltage and temperature. Maintain short sensor wiring and use a quiet analog ground strategy to reduce errors in microvolt-class measurements.
Recommended
Low-Frequency Active Filters
The TS944ID can implement low-frequency active filtering and gain stages where four related amplifier channels are useful. Its 10 kHz gain-bandwidth product supports applications involving slow analog signals, including smoothing, low-pass filtering, and feedback-control error amplifiers. The approximately 1.2 uA supply current reduces the power penalty of keeping analog channels continuously active, while the rail-to-rail output characteristic improves signal range. Component tolerances and amplifier open-loop gain will influence filter accuracy, so those parameters should be checked against the required cutoff and phase response. Decoupling capacitors should connect directly to the supply pins with minimal trace length to reduce supply disturbance and feedback instability.
Recommended
Embedded Control Analog Front Ends
The TS944ID is useful as a compact analog companion to low-power embedded controllers. Four channels can buffer potentiometer outputs, amplify control-loop error signals, or interface slowly changing set-point and feedback voltages. Its low 1.2 uA supply current helps preserve battery life, and operation from 2.5 V fits many low-voltage embedded systems. The -40°C to +85°C range supports industrial temperature requirements, but automotive use requires separate qualification confirmation. Keep analog routing away from switching nodes and processor supply edges. Because all channels share the same supply pins, power-gating and shutdown functions should be designed around the common-device architecture rather than assumed per channel.
Recommended
Precision Voltage and Current Buffering
The TS944ID can buffer low-frequency voltage references, shunt-derived current signals, and other slowly changing sources where four channels simplify implementation. Rail-to-rail output increases available swing on low-voltage rails, and the approximately 1.2 uA supply current keeps continuously powered buffering efficient. This role depends on low input bias current, low offset, and stable behavior near the output rails, so engineers should verify those characteristics for the exact operating conditions. Place sensitive inputs on quiet board regions, use a single-point analog ground return where appropriate, and avoid long parallel traces that can increase coupling. The 10 kHz bandwidth is appropriate for static or slowly varying measurements, not high-speed current transients.
Recommended
Recommended Products Summary
Engineering reference data for TS944ID — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product |
|---|---|
| Brand | STMicroelectronics |
| Package | 14-SOIC (0.154 inch, 3.90 mm width) |
| Number of Channels | 4 circuits |
| Output Type | Rail-to-rail |
| Gain-Bandwidth Product | 10 kHz |
| Supply Current | 1.2 uA |
| Operating Supply Voltage Range | 2.5 V to 10 V |
| Operating Temperature Range | -40°C to +85°C |
Key Differentiators
- Four amplifier channels in one package (vs TS944IDT)
- Low-power operation supports portable instruments (vs TS944IDT)
- Rail-to-rail output improves low-voltage signal range (vs TS944IDT)
Design Notes
Place the supply bypass capacitor immediately across pins 11 and 4, with the capacitor ground end connected to a low-impedance analog-ground return. Keep the TS944ID footprint compatible with the standard 14-pin SOIC land pattern and confirm the pin-1 orientation against the manufacturer package drawing. Route each output directly to its feedback resistor rather than routing through shared traces around the package.
Use short, guarded traces for non-inverting inputs because the TS944ID is intended for low-frequency, low-power signal conditioning. Route inputs away from switching-regulator inductors, power-supply vias, and digital clock lines. If a sensor is remote, buffer it close to the sensor and keep high-impedance input traces short. The 10 kHz gain-bandwidth product makes the device most suitable for slow signals; evaluate a faster amplifier when edge fidelity or broad-band noise rejection is required.
Do not treat rail-to-rail output as proof of rail-to-rail input operation. Before using an input near a supply rail, verify its common-mode range at the minimum and maximum supply voltages. Also account for output swing under load and confirm that the signal bandwidth remains well within the 10 kHz gain-bandwidth product. All four channels share pins 4 and 11, so independent positive and negative supply configurations are not supported.
At the approximately 1.2 uA supply current specified for this micropower amplifier, junction heating is generally insignificant compared with conventional high-current operational amplifiers. Thermal design should instead focus on the surrounding circuit and the total board dissipation. For battery-powered designs, calculate average consumption from the amplifier current, load current, sensor current, and regulator quiescent current; the TS944ID's own contribution alone does not determine battery life.
Compliance Information
The available product information does not explicitly state the TS944ID's RoHS, REACH, AEC-Q100, lead-free, halogen-free, or conflict-minerals status. Request current manufacturer compliance documentation for the exact ordering code before using the device in a regulated design.
