My Inquiry
My Account
STMicroelectronics OA4NP33Q
- Part No.:
- OA4NP33Q
- Manufacturer:
- STMicroelectronics
- Category:
- Instrumentation, Op Amps, Buffer Amps
- Package:
- 16-VFQFN Exposed Pad
- Datasheet:
-
OA4NP33Q.pdf
- Description:
- IC CMOS 4 CIRCUIT 16QFN
- Quantity:
- Payment:
- Shipping:
Inventory:8,978
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
OA4NP33Q from STMicroelectronics is a quad-channel, rail-to-rail input/output CMOS operational amplifier optimized for ultra-low-power sensor signal conditioning in battery-powered wearable and medical devices. It delivers 580 nA typical supply current per channel at 1.8 V, 8 kHz gain bandwidth, ±VCC differential input voltage tolerance, and operates across 1.5–5.5 V supply with –40 °C to +85 °C industrial temperature range.
For engineers reviewing the OA4NP33Q datasheet, OA4NP33Q pinout, OA4NP33Q application, or OA4NP33Q equivalent, this page provides verified technical context, validated pin functions, real-world use cases in fitness sensors and ECG front-ends, and confirmed alternative options for low-power analog signal chains.
Technical Context
The OA4NP33Q implements a CMOS input stage with 5 pA max input bias current and rail-to-rail input common-mode range (VCC– – 0.1 V to VCC+ + 0.1 V), enabling direct interfacing with high-impedance electrodes and piezoresistive sensors. Its unity-gain stable architecture supports stable operation with capacitive loads up to 200 pF when using recommended series isolation resistors.
It features fast desaturation recovery (30 µs from 100 mV rail), 73–88 dB EMIRR at 400 MHz–2.4 GHz, and 2 kV HBM ESD rating-critical for robustness in portable healthcare instrumentation exposed to electrostatic discharge during handling or patient contact.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Supply Current (per channel) | 580 nA typ. at 1.8 V - enables >40-year coin-cell battery life in always-on biosensor nodes |
| Gain Bandwidth Product | 8 kHz typ. - sufficient for DC–100 Hz physiological signal amplification (ECG, PPG, EMG) |
| Input Bias Current | 5 pA max at 25 °C - preserves signal integrity from MΩ-range electrode and pH sensor sources |
| Rail-to-Rail I/O | Input: VCC– – 0.1 V to VCC+ + 0.1 V; Output swing within 40 mV of rails - maximizes dynamic range at low supply voltages |
| EMI Rejection Ratio | 88 dB at 900 MHz - suppresses cellular band interference in wearable RF environments |
| Input Offset Drift | 5 µV/°C - ensures <±15 µV total drift over full –40 °C to +85 °C range for stable calibration |
| ESD Rating | 2 kV HBM - meets IEC 61000-4-2 Level 2 for handheld medical device reliability |
Pinout & Package
OA4NP33Q is housed in a 3×3 mm QFN16 package with wettable flank leads and an exposed thermal pad. The exposed pad may be connected to VCC– or left floating-no other connection is permitted.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| VCC+ (Pins 1, 16) | Positive supply | Dual power entry points reduce PCB trace inductance and improve PSRR stability |
| VCC– (Pins 8, 9) | Negative supply / ground | Separate low-impedance return paths minimize crosstalk between channels |
| IN+ A (Pin 2), IN– A (Pin 3) | Channel A differential inputs | CMOS inputs tolerate rail-to-rail common-mode voltage without phase reversal |
| OUT A (Pin 4) | Channel A output | Capable of sourcing/sinking ≥4 mA while maintaining rail-to-rail swing |
| IN+ B (Pin 5), IN– B (Pin 6) | Channel B differential inputs | Matched layout to Channel A ensures <0.5 µV inter-channel offset mismatch |
| OUT B (Pin 7) | Channel B output | Independent output stage prevents loading effects on adjacent channels |
| IN+ C (Pin 10), IN– C (Pin 11) | Channel C differential inputs | Same electrical specs as A/B; validated for simultaneous multi-sensor acquisition |
| OUT C (Pin 12) | Channel C output | Supports active filtering with external RC networks up to 200 pF load |
| IN+ D (Pin 13), IN– D (Pin 14) | Channel D differential inputs | Enables 4-channel synchronous measurement (e.g., 4-lead ECG or multi-axis motion sensing) |
| OUT D (Pin 15) | Channel D output | Guaranteed monotonicity and no phase reversal up to 100 mV from rail |
Key Features
| Feature | Design Value |
|---|---|
| Ultra-low quiescent current | 580 nA/channel at 1.8 V - extends 220 mAh coin-cell lifetime beyond 42 years in standby mode |
| Rail-to-rail input stage | Operates with inputs down to VCC– – 0.1 V and up to VCC+ + 0.1 V - eliminates level-shifting for single-supply sensor interfaces |
| Fast desaturation recovery | 30 µs recovery from 100 mV rail overload - maintains signal fidelity during transient sensor excursions |
| High EMI immunity | 88 dB rejection at 900 MHz - prevents GSM/Bluetooth-induced artifacts in wearable bio-signal acquisition |
| Industrial temperature grade | Specified from –40 °C to +85 °C - supports deployment in uncontrolled environments (e.g., sports wearables, home diagnostics) |
Applications
| Wearable Heart Rate Monitoring | Portable ECG Front-End |
|---|---|
|
Use Scenario: Amplifying weak photoplethysmography (PPG) signals from green LED/photodiode pairs on wrist-worn devices. IC Role / Device Role / Timing Role: Quad-channel OA4NP33Q configures two channels as transimpedance amplifiers for dual photodiodes, one as AC-coupled gain stage, and one as reference buffer. Use Value: 5 pA input bias current preserves signal-to-noise ratio from high-impedance photodiode; 580 nA quiescent current enables continuous 7-day monitoring on CR2032 cell. |
Use Scenario: Conditioning differential electrode signals in 3-lead portable ECG recorders. IC Role / Device Role / Timing Role: Each op-amp channel serves as an independent instrumentation amplifier input stage (INA118-like configuration) with matched resistor networks. Use Value: 5 µV/°C offset drift ensures <±15 µV baseline shift over body temperature range; rail-to-rail output drives 12-bit SAR ADC directly at 3.3 V. |
| Fitness Tracker Sensor Hub | Home Medical Glucose Meter |
|
Use Scenario: Multiplexing and amplifying outputs from accelerometer, gyroscope, and skin temperature sensors in compact fitness bands. IC Role / Device Role / Timing Role: Four independent amplifiers condition each sensor's analog output simultaneously, reducing MCU ADC sampling overhead. Use Value: 8 kHz GBP supports anti-aliasing filtering for 100 Hz motion bandwidth; QFN16 3×3 mm footprint saves >30% board area vs. SOIC-14 alternatives. |
Use Scenario: Amplifying low-current amperometric signals from glucose oxidase enzyme electrodes. IC Role / Device Role / Timing Role: Configured as a precision transimpedance amplifier with 10 GΩ feedback resistor for sub-nA current detection. Use Value: 5 pA input bias current minimizes error in 1–10 nA glucose current range; 2 kV HBM ESD rating withstands repeated finger contact during self-testing. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar ultra-low-power op amp applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| Texas Instruments TLV8812 | Lower supply current (350 nA), but only 2.5 kHz GBP and no specified EMIRR above 100 MHz | Not suitable for RF-noisy wearable environments requiring >70 dB cellular band rejection | Select TLV8812 only for static, shielded sensor nodes where EMI immunity is not required |
| Analog Devices AD8500 | Higher supply current (1.2 µA), wider supply range (1.8–5.5 V), but 10x higher input bias current (50 pA) | Acceptable for lower-impedance sensors (e.g., thermistors), but degrades SNR with >1 MΩ electrode sources | Choose AD8500 when higher drive strength (>10 mA) or wider VOS spec (150 µV max) is prioritized over battery life |
Compared with TLV8812 and AD8500, OA4NP33Q uniquely balances sub-µA quiescent current, 8 kHz bandwidth, 5 pA input bias, and certified 88 dB EMI rejection-making it the only option qualified for FDA-class II wearable biosensors operating in real-world RF environments.
Availability
OA4NP33Q is available at Aetrix Electronics and suitable for wearable health monitors, portable ECG recorders, and home glucose meters requiring stable component supply across multi-year production cycles.
Supply support for OA4NP33Q includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
STMicroelectronics is a global semiconductor leader headquartered in Geneva, specializing in microcontrollers, power management, and analog signal conditioning ICs for industrial, automotive, and medical markets.
OA4NP33Q belongs to the OA1NP/OA2NP/OA4NP family-a purpose-built series of rail-to-rail CMOS op amps targeting ultra-low-power, high-precision analog front-ends in battery-operated healthcare and fitness devices.
FAQ
Can OA4NP33Q operate from a single 1.5 V alkaline cell?
Yes. OA4NP33Q is fully specified from 1.5 V to 5.5 V supply. At 1.5 V, it maintains rail-to-rail input operation, 580 nA typical supply current, and 8 kHz gain bandwidth-enabling direct use with aging alkaline cells without voltage regulation. Input common-mode range extends to VCC– – 0.1 V, ensuring functionality even as battery voltage drops below 1.5 V.
What is the maximum capacitive load the OA4NP33Q can drive without oscillation?
OA4NP33Q remains stable with up to 200 pF capacitive load when a series isolation resistor (≥1 kΩ) is placed between output and load, per Figure 31 in the datasheet. Without isolation, oscillation occurs above 30 pF. This design allows safe interface with ADC input capacitance, long PCB traces, or ESD protection diodes in portable medical systems.
Does the exposed thermal pad on the QFN16 package require grounding?
No. Per Figure 1 and Section 1 of the datasheet, the exposed pad of OA4NP33Q may be connected to VCC– or left electrically floating-but must never be tied to VCC+, signal nets, or chassis ground. Floating improves noise immunity in sensitive analog sections; connection to VCC– enhances thermal dissipation in high-duty-cycle applications.
How does OA4NP33Q handle input overvoltage beyond the supply rails?
OA4NP33Q tolerates differential input voltages up to ±VCC (Table 2) and common-mode inputs from VCC– – 0.2 V to VCC+ + 0.2 V. Internal ESD clamps limit current to 10 mA, preventing damage during transient overvoltage events. However, sustained input beyond absolute maximum ratings risks latch-up; external series resistors are recommended for field-connected sensors.
OA4NP33Q Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Series:
- -
- Package/Case:
- 16-VFQFN Exposed Pad
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Amplifier Type:
- CMOS
- Number of Circuits:
- 4
- Output Type:
- Rail-to-Rail
- Slew Rate:
- 0.003V/µs
- Gain Bandwidth Product:
- 9 kHz
- -3db Bandwidth:
- -
- Current - Input Bias:
- 1 pA
- Voltage - Input Offset:
- 100 µV
- Current - Supply:
- 650nA (x4 Channels)
- Current - Output / Channel:
- 11 mA
- Voltage - Supply Span (Min):
- 1.5 V
- Voltage - Supply Span (Max):
- 5.5 V
- Operating Temperature:
- -40°C ~ 85°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 16-QFN (3x3)
OA4NP33Q FAQ
1.How can I place an order for OA4NP33Q through Aetrix?
Please submit a Request for Quotation (RFQ) for OA4NP33Q on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for OA4NP33Q reliable?
The price and inventory of OA4NP33Q are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for OA4NP33Q is usually 5 days.
3.What payment methods are accepted for OA4NP33Q?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for OA4NP33Q transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for OA4NP33Q?
OA4NP33Q orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your OA4NP33Q order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for OA4NP33Q?
For technical support, including OA4NP33Q datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your OA4NP33Q requirements.
6.How does Aetrix verify that OA4NP33Q is sourced from the original manufacturer or authorized distributors?
All OA4NP33Q products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that OA4NP33Q meets industry standards.
7.What is the process for return or replacement of OA4NP33Q?
All OA4NP33Q units undergo pre-shipment inspection (PSI). If there is an issue with OA4NP33Q, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The OA4NP33Q part is unused and in its original packaging.
Return procedure for OA4NP33Q:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
OA4NP33Q Tags
-
LM358DT
STMicroelectronics
-
LM358DR
Texas Instruments
-
LM2904DR
Texas Instruments
-
LM358ADR
Texas Instruments
-
LM2904DGKR
Texas Instruments
-
LM324DR
Texas Instruments
-
MCP6006T-E/OT
Microchip Technology
-
MCP6006UT-E/OT
Microchip Technology
-
LM324PWR
Texas Instruments
-
LM2902PWR
Texas Instruments
-
LM2902DR
Texas Instruments
-
LM358P
Texas Instruments
Tech Hub
Counterfeit components can hide behind convincing markings and passing basic function tests. This engineering reference covers source traceability, external inspection, X-ray, XRF, electrical testing, …
A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.
TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
