Affordable Precision Current Sensing
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onsemi brings affordability to precision current sensing with the addition of the NCS199 & NCS21x family of devices. NCS199 & NCS21x are resistor shunt based devices, providing cost savings and PCB size reductions over hall sensor based solutions. |
| High Side vs. Low Side Sensing |
High Side Sensing  Advantages • Detects load shorts • No ground path resistance Disadvantages • More expensive than low side sensing • No ground path resistance |
Low Side Sensing Advantages • Simple Implementation • Inexpensive Disadvantages • Cannot detect load shorts • Resistance in ground path |
| Key Applications | |
| Powertrain • 12V-48V DC-DC Converters (High Side Current Sensing) • Electric Oil Pump, 3 Phase Motor (Low Side Current Sensing) • HEV Inverter, 3 Phase Motor (Low Side Current Sensing) • E-bike, 3 Phase Motor (Low Side Current Sensing) • Solenoid/Glow Plug Control - Diesel (High Side Current Sensing) • Gasoline Direct Injection (Low Side Current Sensing) Body Control & Safety • Electric Parking Brake (Low Side Current Sensing) • Electronic Power Steering (Low Side Current Sensing) • Active Suspension (Signal Conditioning) • Next Gen. PM Emissions Sensors (Precision Signal Conditioning) • Rearview Mirror Dimming (Driving Electro-chromatic Element) Multimedia & Infotainment • "Qi" Wireless Charging (High Side Current Sensing) • Microphone Pre Amplifier (Low Noise Op-Amp) Lighting • SMPS Controller Feedback Loop (High Side Current Sensing) • Rear Dimming Light (RDL) (Low Side Current Sensing) |
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NCS199 & NCS21x Current Sense Amplifiers The NCS199 and NCS21x devices are voltage output current shunt monitors that measure voltage across shunts at common-mode voltages from -0.3 V to 26 V, independent of supply voltage. Multiple fixed gains are available: 50 V/V, 75 V/V, 100 V/V, 200 V/V, 500 V/V, or 1000 V/V. The low offset of the zero-draft architecture enables current sensing with maximum drops across the shunt as low as 10 mV full-scale. The devices cab operate from a single +2.7 V to +26 V power supply, drawing a maximum of 100 µA of supply current. All versions are specified over the extended operating temperature range (–40° C to +125° C). |
| Features • Low offset drift • Wide common mode input range -0.3 V to 26 V • Supply Voltage range from 2.7 V to 26 V • Low offset voltage of ±60 µV, ±100 µV, and ±150 µV Max • ±1% and ±1.5 % Accuracy for NCS21x & NCS199 respectively |
Benefits • High Precision Current Sensing • High-Side Current Sensing for High Voltage Systems • Flexible System Supply Voltage • Low Value Current Sense Resistors for Better Power Efficiency • Temperature Sensitive Applications |
| Part Numbers Available from RS | Gain (V/V) | Gain Error Max (%) | GBW Typ (MHz) | VIOMax (mV) | VIO Drift (µV/°C) |
| NCS210SQT2G | 200 | ±1.0 | 0.040 | ±0.060 | 0.6 |
| NCS211SQT2G | 500 | ±1.0 | 0.025 | ±0.060 | 0.6 |
| NCS214SQT2G | 100 | ±1.0 | 0.060 | ±0.060 | 0.6 |
| NCS199A1SQT2G | 50 | ±1.5 | 0.100 | ±0.150 | 2.0 |
| NCS199A2SQT2G | 100 | ±1.5 | 0.060 | ±0.150 | 0.6 |
| NCS199A3SQT2G | 200 | ±1.5 | 0.040 | ±0.150 | 0.6 |
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