NCS199A1RSQT2G - Zero-Drift Current Sense Amp, Gain 50 | onsemi
N.º da peça: NCS199A1RSQT2G ✓ Ativo| Qtd. | Preço unitário | Total |
|---|---|---|
| 1 | $0.99 | $0,99 |
| 10 | $0.89 | $8,90 |
| 100 | $0.74 | $74,00 |
| 500 | $0.59 | $295,00 |
| 1.000 | $0.48 | $480,00 |
NCS199A1RSQT2G Visão geral
A current sense amplifier (CSA) is a type of instrumentation amplifier that converts a small differential voltage developed across a shunt resistor into a ground-referenced output voltage proportional to load current. CSAs belong to the broader family of analog signal-conditioning ICs and are essential building blocks in power management, motor control, and battery-monitoring systems where high common-mode rejection, low offset, and small package size are required.
Key features include a fixed gain of 50 V/V (other family members NCS199A2R = 100 V/V, NCS199A3R = 200 V/V/Current = 50 mA), bidirectional sensing capability, 60 uV maximum input offset voltage (zero-drift chopper architecture), and a -3 dB bandwidth of approximately 90 kHz. The zero-drift internal architecture continuously cancels 1/f noise and offset drift over temperature, achieving typical input offset drift of 0.5 uV/C.
The NCS199A1R uses a proprietary auto-zero / chopper-stabilized topology that eliminates the need for external precision resistors and provides excellent long-term stability. Common-mode rejection ratio (CMRR) exceeds 100 dB at DC, and the small SOT-363 footprint allows placement directly at the shunt resistor for minimum parasitic errors. The part also includes an internal EMI filter and ESD protection rated at 4 kV HBM.
Typical applications include battery-pack current monitoring in power tools and e-bikes, motor-control current loops in BLDC drivers, solar MPPT input current sensing, server and telecom -48 V hot-swap current monitoring, and USB-C PD current telemetry. In all cases the wide -0.3 V to 26 V common-mode range allows the same IC to be used on either rail of the load.
When designing with this part, keep the input differential loop to the shunt as short as possible and place a 10 nF differential capacitor across the IN+ and IN- pins to suppress switching noise from PWM-driven loads. Ensure the output does not drive more than 1 nF of capacitance without a series isolation resistor to maintain stability.
Alternativas drop-in para NCS199A1RSQT2G — mesmo encapsulamento, compatível pino a pino. Peças de encapsulamento diferente que exigem retrabalho na PCB são excluídas.
Ferramenta de comparação rápida — selecione peças alternativas para comparação lado a lado:
NCS199A2RSQT2G
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
NCS199A3RSQT2G
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
NCS199A1SQT2G
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
NCS199A2SQT2G
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
INA180A1IDCKR
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
NCS199A1RSQT2G Classificações máximas e características elétricas
| Função | Current sense amplifier (voltage output, bidirectional) |
| Canais | 1 |
| Gain | 50 V/V (fixed) |
| Common-Mode Input Range | -0.3 V to 26 V |
| Supply Voltage Range | 2.2 V to 26 V |
| Input Offset Voltage (max) | 60 uV (zero-drift chopper) |
| Input Offset Drift (typ) | 0.5 uV/°C |
| CMRR | 100 dB at DC |
| -3 dB Bandwidth (typ) | 90 kHz |
| Output Swing | Rail-to-rail |
| Slew Rate | 1 V/us |
| Faixa de temperatura de operação | -40°C to +125°C |
| Encapsulamento | SC-88 / SC-70-6 / SOT-363 (6-pin) |
| Tipo de montagem | Surface Mount |
| ESD Rating (HBM) | 4000 V |
| Nível MSL | 1 |
| Status RoHS | Compliant |
Configuração de pinos do NCS199A1RSQT2G
| Pino 1 | IN+ — Non-inverting differential input from shunt |
| Pino 2 | IN- — Inverting differential input from shunt |
| Pino 3 | GND — Ground reference |
| Pino 4 | OUT — Ground-referenced amplified output voltage |
| Pino 5 | VS — Supply voltage (2.2 V to 26 V) |
| Pino 6 | NC — Not connected (per datasheet) |
Aplicações típicas
NCS199A1RSQT2G é adequado para 6 aplicaçãos: Battery Pack Current Monitoring, Motor Control Current Loop, Solar MPPT Input Current Sensing, Server / Telecom -48V Hot-Swap Current Monitor, USB-C PD Current Telemetry, Power Supply Over-Current Detection.
Battery Pack Current Monitoring
The NCS199A1RSQT2G's -0.3 V to 26 V common-mode range and zero-drift chopper architecture make it ideal for battery-pack current telemetry in power tools, e-bikes, and portable medical devices. The 50 V/V fixed gain with 60 uV maximum input offset provides accurate coulomb-counting measurements across the full -40°C to +125°C automotive temperature grade, while the SOT-363 footprint fits inside space-constrained 18650/21700 cell holders. Placed directly at the high-side shunt with a 10 nF input capacitor, the part achieves sub-1% current-measurement accuracy without precision external resistors, unlike discrete op-amp solutions that require matched resistor networks and thermal-cancellation circuitry.
Recomendado
Motor Control Current Loop
In BLDC and stepper motor drives, the NCS199A1RSQT2G provides bidirectional current sensing for FOC (field-oriented control) phase-current feedback. The -0.3 V to 26 V common-mode range covers 12 V and 24 V motor rails including back-EMF transients, while the 90 kHz -3 dB bandwidth is sufficient for motor PWM frequencies up to 30 kHz without aliasing. The zero-drift 0.5 uV/°C offset drift maintains current-loop accuracy over temperature without periodic recalibration. Placed at the low-side shunt of each phase leg with an RC low-pass filter, the CSA feeds the microcontroller ADC for closed-loop torque control.
Recomendado
Solar MPPT Input Current Sensing
The NCS199A1RSQT2G is well-suited to solar photovoltaic MPPT input current sensing in 12 V and 24 V battery-based PV systems. Its -0.3 V to 26 V common-mode range covers the full PV panel voltage range plus battery float transients, and its zero-drift chopper architecture eliminates 1/f noise at the low PWM duty cycles characteristic of boost MPPT converters. The 90 kHz bandwidth is wide enough for MPPT control loops below 10 kHz while rejecting switching noise from the boost FET. Housed in a SOT-363 package, it fits inside IP67 junction boxes alongside the panel's blocking diode and TVS protection.
Recomendado
Server / Telecom -48V Hot-Swap Current Monitor
In -48 V telecom and server hot-swap controllers, the NCS199A1RSQT2G can be used on the negative return rail because its common-mode range extends down to -0.3 V, well below the -48 V return potential when biased from a positive 3.3 V or 5 V supply. The 100 dB CMRR at DC rejects ripple on the -48 V rail, while the rail-to-rail output drives the hot-swap controller's analog current-limit input directly. Its SOT-363 footprint and 4 kV HBM ESD rating make it rugged enough for line-card insertion events without external protection.
Recomendado
USB-C PD Current Telemetry
USB-C Power Delivery requires accurate load-current telemetry for protocol reporting and cable-compensation calculations. The NCS199A1RSQT2G placed at the VBUS high-side rail with a 5 mOhm shunt produces a 250 mV full-scale signal at 5 A load, well within the 26 V common-mode rating for 20 V PD contracts. The 90 kHz bandwidth tracks PD load steps with sub-100 us settling, and the SOT-363 footprint fits inside Type-C connector PCBs. Zero-drift offset eliminates the periodic recalibration needed for low-side op-amp sensing solutions.
Recomendado
Power Supply Over-Current Detection
The NCS199A1RSQT2G serves as the current-sense front-end for over-current protection (OCP) in isolated and non-isolated DC-DC converters. Its zero-drift architecture detects fault currents within 1% accuracy across the full industrial temperature range, and its 60 uV maximum offset avoids false trips at low currents. The SOT-363 package fits alongside the converter's main inductor and switching FETs, and the rail-to-rail output drives the PWM controller's ILIM pin directly without external level-shifting. Bidirectional sensing enables reverse-current detection for synchronous-rectifier protection.
Recomendado
Resumo dos produtos recomendados
Dados de referência de engenharia para NCS199A1RSQT2G — comparação, orientação de projeto e informações de conformidade.
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Comparação com alternativas
| Parâmetro | Este produto | NCS199A2RSQT2G | NCS199A3RSQT2G | NCS199A1SQT2G | NCS199A2SQT2G | INA180A1IDCKR |
|---|---|---|---|---|---|---|
| Package | SC-88 / SC-70-6 / SOT-363 (6-pin) | SC-88 / SC-70-6 / SOT-363 (6-pin) - same | SC-88 / SC-70-6 / SOT-363 (6-pin) - same | SC-88 / SC-70-6 / SOT-363 (6-pin) - same | SC-88 / SC-70-6 / SOT-363 (6-pin) - same | SC-70 (DCK-6) - same pin count |
| Brand | onsemi | onsemi | onsemi | onsemi | onsemi | Texas Instruments |
| Gain | 50 V/V | 100 V/V | 200 V/V/Current = 50 mA | 50 V/V | 100 V/V | 20 V/V |
| Common-Mode Range | -0.3 V to 26 V | -0.3 V to 26 V | -0.3 V to 26 V | -0.3 V to 26 V | -0.3 V to 26 V | -18 V to 26 V |
| Supply Voltage | 2.2 V to 26 V | 2.2 V to 26 V | 2.2 V to 26 V | 2.2 V to 26 V | 2.2 V to 26 V | 2.7 V to 5.5 V |
| Input Offset Voltage (max) | 60 uV | 60 uV | 60 uV | 60 uV | 60 uV | 150 uV |
| -3 dB Bandwidth (typ) | 90 kHz | 60 kHz | 40 kHz | 90 kHz | 60 kHz | 350 kHz |
| Operating Temperature | -40°C to +125°C | -40°C to +125°C | -40°C to +125°C | -40°C to +125°C | -40°C to +125°C | -40°C to +125°C |
Principais diferenciais
- Wider common-mode range than most competing CSAs (vs INA180A1IDCKR)
- Lowest input offset drift in its CSA class (vs INA180A1IDCKR)
- Bidirectional sensing without additional components (vs NCS199A2RSQT2G)
Notas de projeto
Keep the differential traces from the shunt resistor to IN+ and IN- as short and symmetric as possible; route them as a tightly coupled differential pair over a continuous ground plane. Place a 10 nF ceramic capacitor directly between IN+ and IN- as close to the IC as possible to filter common-mode and differential-mode switching noise from PWM-driven loads. Estimated: shunt-to-input trace lengths > 5 mm begin to degrade CMRR noticeably above 10 kHz.
Do not place the part more than 10 mm from the shunt resistor - parasitic inductance in the input traces creates a voltage spike during high di/dt load transients that can exceed the differential input rating. The bidirectional input can withstand -5 V to +26 V differential transients, but sustained over-voltage degrades accuracy. For high-side sensing, ensure the supply voltage (VS) is present before the common-mode voltage is applied, or the part will enter an undefined output state.
Use a 4-layer PCB with a dedicated ground plane beneath the part to maximize CMRR and minimize EMI pickup. Connect the GND pin directly to the ground plane via a via-in-pad if the design supports it. Place a 0.1 uF decoupling capacitor on the VS pin within 3 mm and a bulk 1 uF tantalum or ceramic on the supply rail. The exposed thermal pad (if any) should be soldered to the ground pour for thermal spreading, although the SOT-363 dissipates under 100 mW in typical current-sensing applications.
Informações de conformidade
RoHS compliant per onsemi product page. The NCS199A1R family is not specifically AEC-Q100 qualified in the public datasheet; verify automotive qualification status with onsemi FAE for AEC-Q100 grade-1 requirements.
