BSS123IXTSA1 - 100V N-Ch 190mA OptiMOS MOSFET | Infineon
MPN: BSS123IXTSA1 ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $0.42 | $0.42 |
| 10 | $0.35 | $3.50 |
| 100 | $0.22 | $22.00 |
| 500 | $0.16 | $80.00 |
| 1,000 | $0.13 | $130.00 |
| 3,000 | $0.11 | $330.00 |
Drop-in alternatives for BSS123IXTSA1 — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
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2N7002L
✅ Drop-In✓ In Stock
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View Datasheet →2N7002L
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View Datasheet →BSS123IXTSA1 Maximum Ratings & Electrical Characteristics
| Transistor Type | N-Channel MOSFET |
| Technology | OptiMOS Small-Signal |
| Drain-Source Voltage (VDS) | 100 V |
| Continuous Drain Current (ID) at TA=25C | 190 mA |
| Power Dissipation (PD) at TA=25C | 500 mW |
| RDS(on) (typical, VGS=10 V) | 2.4 ohm |
| RDS(on) (max per family datasheet) | 6 ohm |
| Package | PG-SOT-23-3 (SOT-23-3) |
| Mounting Type | Surface Mount |
| Operating Temperature Range | -55C to +150C (per family datasheet) |
| Qualification | Industrial |
| Configuration | Single N-Channel |
| Lead-Free / RoHS | Yes (per distributor listing) |
| Gate Drive Logic Level | Logic-level compatible |
BSS123IXTSA1 Pin Configuration
| Pin 1 | Gate — MOSFET gate control input; logic-level compatible |
| Pin 2 | Source — MOSFET source terminal; typically tied to circuit ground in low-side switching |
| Pin 3 | Drain — MOSFET drain terminal; switches the load |
Safe Operating Area (SOA) & Thermal Characteristics
No official SOA curve available for this component. Always operate within absolute maximum ratings specified in the datasheet. Ensure adequate cooling and derate as needed.
Typical Applications
BSS123IXTSA1 is suitable for 6 applications: Low-Side Switching in Battery Management, Logic-Level Level Shifter 3.3V to 12V, Signal Multiplexing and Analog Switching, LED Driver and Indicator Switch, Relay and Solenoid Driver Stage, IoT Sensor Node Load Switching.
Low-Side Switching in Battery Management
The BSS123IXTSA1 serves as a low-side switch in battery management and protection circuits, where its 100 V VDS rating easily covers 4S to 10S lithium packs (up to 42 V nominal). With 190 mA continuous drain current and 500 mW power dissipation, it can drive fuel-gauge enable lines, LED status indicators, and auxiliary load-disconnect FETs. The 2.4 ohm typical RDS(on) at VGS=10 V keeps conduction loss modest. Designers must observe the SOT-23-3 thermal envelope and use adequate copper pour to keep junction temperature within the -55C to +150C operating range during high-duty-cycle switching.
Recommended
Logic-Level Level Shifter 3.3V to 12V
Used as a low-side level translator, the BSS123IXTSA1 accepts 3.3 V GPIO drive from an MCU and switches 12 V loads on its drain. Its logic-level threshold permits direct GPIO connection without a gate driver. The 100 V VDS provides ample margin for 24 V industrial rails. A 100 kohm gate-source pull-down resistor prevents floating-gate turn-on during MCU reset, while the 500 mW dissipation limit keeps the SOT-23-3 package within thermal limits for typical pulse-driven signal lines and small relay coils.
Recommended
Signal Multiplexing and Analog Switching
In test and instrumentation equipment, the BSS123IXTSA1 multiplexes low-current analog signals between ADC channels and sensor front-ends. Its low gate charge and fast switching edges support multiplex rates well into the kHz range. The 100 V rating allows switching of higher-voltage transducer outputs when needed. Designers should note that the drain-source capacitance forms an RC network with source impedance, which may introduce settling-time artifacts in high-precision measurement paths.
Recommended
LED Driver and Indicator Switch
The BSS123IXTSA1 efficiently PWM-drives indicator LEDs, status lamps, and optocoupler input diodes from a microcontroller GPIO. At 190 mA continuous current, it handles most discrete indicator LEDs and optocoupler inputs directly. The 100 V VDS allows driving high-side LED strings in industrial HMI panels. For higher currents or multi-channel LED matrices, designers should consider dedicated LED drivers such as the BTS3011TEATMA1 to offload thermal stress from the small SOT-23-3 footprint.
Recommended
Relay and Solenoid Driver Stage
The BSS123IXTSA1 drives small signal relays and solenoids in industrial control and white-goods applications, switching inductive loads on its drain. The 100 V VDS withstands flyback spikes when paired with a flyback diode across the coil. Continuous current of 190 mA covers most sub-miniature signal relays; larger contactors require a higher-current MOSFET or a dedicated smart switch such as the BTS500801TEAAUMA1. Place a TVS or snubber across the drain-source for unclamped inductive loads.
Recommended
IoT Sensor Node Load Switching
In battery-powered IoT sensor nodes, the BSS123IXTSA1 enables duty-cycled power to sub-circuits such as environmental sensors, radios, and ADCs, extending battery life through sub-microamp off-state leakage. Its small SOT-23-3 footprint fits space-constrained wearable and smart-home designs. The 100 V VDS rating supports USB-C VBUS hot-swap protection up to 20 V. Pair with a low-quiescent LDO such as the TLE42662GSV33HTMA2 to maintain overall node sleep current below 10 uA.
Recommended
Recommended Products Summary
Engineering reference data for BSS123IXTSA1 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | BSS123I | BSS123 | VB1106K | 2N7002 |
|---|---|---|---|---|---|
| Brand | Infineon Technologies | Infineon Technologies | Infineon Technologies | [DATA_NEEDED: VB1106K manufacturer] | onsemi |
| Package | SOT-23-3 (PG-SOT-23-3) | SOT-23-3 - same | SOT-23-3 - same | SOT-23-3 - same | SOT-23-3 - same |
| Drain-Source Voltage (VDS) | 100 V | 100 V | 100 V | 100 V (per cross-reference data) | 60 V |
| Continuous Drain Current (ID) | 190 mA | 190 mA | 190 mA | [DATA_NEEDED: ID rating] | 200 mA |
| Power Dissipation (PD) | 500 mW | 500 mW | 500 mW | [DATA_NEEDED: PD rating] | 350 mW |
| RDS(on) max @ VGS=10V | 6 ohm | 6 ohm | 6 ohm | [DATA_NEEDED: RDS(on) max] | 7.5 ohm |
| Technology | OptiMOS Small-Signal | OptiMOS Small-Signal | Standard N-channel | [DATA_NEEDED: process] | Standard N-channel |
| Qualification | Industrial | Industrial | Industrial | [DATA_NEEDED: qualification] | Industrial |
Key Differentiators
- Higher VDS rating (100 V) versus 2N7002 (60 V) (vs 2N7002 (onsemi))
- OptiMOS process technology (vs BSS123 (legacy Infineon))
- Higher power dissipation (500 mW vs 350 mW for 2N7002) (vs 2N7002 (onsemi))
Design Notes
The BSS123IXTSA1 has a power dissipation limit of 500 mW at TA=25C in the SOT-23-3 package. With a typical theta_JA around 357 C/W on a standard JEDEC 1sq-in 1oz copper test board, the device derates linearly to near 0 mW at 150C junction temperature. For continuous loads above 100 mA, attach the SOT-23-3 drain pad (pin 3) to at least 100 sq mm of 1 oz copper pour on both PCB layers to reduce theta_JA below 200 C/W. Estimated: at 100 mA continuous and VDS=10 V, conduction loss is approximately 0.24 W, requiring a heatsink copper pour of 200 sq mm to keep Tj below 100C at 50C ambient.
Use the standard SOT-23-3 land pattern (IPC-7351 nominal footprint) for drop-in compatibility with 2N7002, BSS138, and similar parts. Place a 100 kohm gate-source pull-down resistor within 2 mm of the gate pin to prevent floating-gate turn-on during MCU reset or hot-plug events. Keep the drain trace short and direct to minimize parasitic inductance, especially when switching inductive loads. A small TVS or Schottky flyback diode across the load is recommended for relay or solenoid drive applications.
Do not assume the BSS123IXTSA1 will fully enhance at 2.5 V gate drive - the threshold voltage is typically 1-2 V and RDS(on) is only specified at VGS=10 V. For 3.3 V-only designs, verify that the actual RDS(on) at VGS=3.3 V still meets your load-current budget. Never operate the device above the 100 V VDS rating, even transiently - inductive load spikes can easily exceed VDS and cause avalanche breakdown. For unclamped inductive switching, add a TVS or RC snubber rated below 80% of VDS(max).
Compliance Information
RoHS and lead-free per DigiKey and Mouser distributor listings; REACH and conflict-minerals compliance per Infineon product page. Industrial qualification only - not AEC-Q100 qualified for automotive.
