BTS3800SLHTSA1 - 350mA Smart Low-Side Switch, 0.8Ω | Infineon
MPN: BTS3800SLHTSA1 ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $0.79 | $0.79 |
| 10 | $0.65 | $6.50 |
| 100 | $0.48 | $48.00 |
| 500 | $0.41 | $205.00 |
| 1,000 | $0.37 | $370.00 |
| 3,000 | $0.32 | $960.00 |
BTS3800SLHTSA1 Overview
A smart low-side switch is a discrete-replacement IC that sits between a microcontroller GPIO and a ground-referenced load such as a relay, solenoid, valve, or LED string. By moving the high-current path off the MCU and onto the switch, the design gains fault isolation, accurate current limiting, and thermal protection. The BTS3800SL belongs to the broader power-management category, specifically the low-side driver / power-distribution switch sub-category that complements high-side PROFET devices in body-control modules.
Key features include 41 V drain-to-source voltage rating for harsh load-dump transients, an operating input voltage range of approximately 2.7 V to 5.5 V at the logic/IN pin, typical 0.8 Ω R_DS(on) at 25 °C, integrated overtemperature shutdown with auto-restart, overcurrent limitation, and overvoltage clamping on the output. The 5-pin PG-SCT595 (gull-wing) footprint occupies roughly 6.5 mm × 4.0 mm on the PCB and supports standard reflow profiles.
The device is built on Infineon's automotive-qualified smart-power BCDMOS process, which co-integrates the analog control block, charge pump, and the vertical N-channel output DMOS into one die. This monolithic integration is what enables the small 5-pin outline while still providing the full protection and diagnostic feature set normally seen in larger SO-8 parts.
Typical applications include automotive relay and solenoid drivers (door locks, mirror adjust, seat modules), LED string drivers for interior lighting and status indication, small DC motor drivers for HVAC flaps and mirror fold, and industrial 24 V PLC discrete outputs where 350 mA load current is sufficient.
When designing with this part, the user should respect the PCB thermal guidelines in the manufacturer's datasheet: the exposed die pad must be soldered to a copper area of at least 1 cm² to keep R_thJA within the safe operating envelope, and a freewheeling diode is mandatory for inductive loads.
This page consolidates distributor pricing, AEC-Q100 cross-brand drop-in alternatives, and practical layout notes that go beyond the manufacturer datasheet, enabling rapid engineering qualification and sourcing decisions.
Drop-in alternatives for BTS3800SLHTSA1 — 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 BTS3800SLHTSA1 (same form factor and footprint) — differing in Continuous Load Current, Output Configuration, Package, Switch Type.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
BTS3800SL
✅ Drop-In📋 Reference alternative (not in catalog)
BTS3800SLHTSA1 Maximum Ratings & Electrical Characteristics
| Part Number | BTS3800SLHTSA1 |
| Manufacturer | Infineon Technologies |
| Product Family | Classic HITFET |
| Switch Type | Low-Side, N-Channel MOSFET |
| Number of Channels | 1 |
| Output Configuration | 1:1 (Single input to single output) |
| Continuous Load Current | 0.35 A (350 mA) |
| On-Resistance R_DS(on) (typ.) | 0.8 Ω |
| Drain-Source Voltage V_DS (max) | 41 V |
| Input Logic Voltage Range | 2.7 V to 5.5 V |
| Package | PG-SCT595-5-1 (5-pin, gull-wing SMD) |
| AEC-Q100 Qualification | Qualified (automotive grade) |
| Embedded Protections | Overtemperature shutdown, overcurrent limit, overvoltage clamp, ESD protection |
| RoHS Status | Compliant (per Infineon product page) |
| Mounting Type | Surface Mount |
BTS3800SLHTSA1 Pin Configuration
| Pin 1 | IN — Logic input from MCU (3.3 V / 5 V CMOS level) |
| Pin 2 | GND — Ground return for logic and power |
| Pin 3 | OUT (Drain) — Open-drain MOSFET output to the load |
| Pin 4 | VS / Sense — Supply sense / battery feed for logic |
| Pin 5 | NC / Thermal Pad — Not connected electrically; solder to copper for thermal dissipation |
Typical Applications
BTS3800SLHTSA1 is suitable for 6 applications: Automotive Relay Driver, Automotive LED String Driver, Solenoid Valve Driver (HVAC / Body), Industrial 24 V PLC Discrete Output, Small DC Motor Driver (Mirror / Flap), Power-Distribution Switch (Replacing Discrete MOSFET + Fuse).
Automotive Relay Driver
The BTS3800SLHTSA1's 0.35 A continuous current, 0.8 Ω R_DS(on), and 41 V drain rating make it a strong fit for automotive PCB relays under 400 mA coil current, including door-lock relays, mirror-fold relays, and seat-adjustment relays. Placed between the MCU GPIO and the relay coil with the load returned to ground, it dissipates roughly 0.1 W at 350 mA, well within the PG-SCT595 thermal envelope. Its embedded overcurrent and overtemperature protection means a stuck coil or wiring short triggers auto-restart shutdown rather than a fire hazard, which is a key safety requirement for ISO 26262 body-control modules.
Recommended
Automotive LED String Driver
For LED strings in interior lighting, ambient trim, and dashboard indicators, the BTS3800SLHTSA1's low-side topology and current-limit function allow precise PWM dimming at frequencies up to 1 kHz. Designers typically place the LEDs on the high side tied to V_battery through a ballast resistor, with the BTS3800SLHTSA1 sinking the ground return. The 0.8 Ω R_DS(on) keeps the dissipation low - for example at 100 mA LED current, switch dissipation is only 8 mW - making it ideal for high-ambient-temperature headliner and footwell installations.
Recommended
Solenoid Valve Driver (HVAC / Body)
HVAC mode doors, mirror adjust, and trunk-release solenoids typically draw 200-350 mA, squarely within the BTS3800SLHTSA1 envelope. The device's integrated overvoltage clamp on the drain pin is critical for driving inductive loads, as it absorbs the flyback pulse without an external TVS - although a freewheeling diode is still recommended by Infineon for solenoid demagnetization. At a 200 mA load with 12 V supply, on-state dissipation is 32 mW per switch, so no heatsink copper beyond standard 1 oz pours is required.
Recommended
Industrial 24 V PLC Discrete Output
The BTS3800SLHTSA1 is a drop-in low-side output for industrial 24 V PLC modules driving pilot lamps, small contactors, and signal relays. With a 41 V drain rating, the device tolerates the 24 V supply plus inductive transient spikes that are typical on factory floors. The 2.7 V to 5.5 V logic input range makes it compatible with 3.3 V and 5 V MCUs, allowing direct GPIO connection without level shifters. The part's AEC-Q100 grade is over-qualified for indoor PLC use but provides extra margin for outdoor cabinets and harsh industrial environments.
Recommended
Small DC Motor Driver (Mirror / Flap)
Small DC motors for mirror-fold, headlight-leveling, and HVAC mode flaps typically operate below 300 mA continuous. The BTS3800SLHTSA1, paired with an H-bridge driver, can be used for one half of the bridge on the low side; however, for full H-bridge motor control, two devices in antiparallel configuration are required. Its embedded thermal shutdown is a key safety net for stalled-motor conditions where current rises to several amps - the device will auto-restart once the rotor is freed.
Recommended
Power-Distribution Switch (Replacing Discrete MOSFET + Fuse)
The BTS3800SLHTSA1 replaces a discrete N-channel MOSFET plus resettable PTC fuse in a power-distribution path. Compared with discrete solutions, it saves roughly 30 % of PCB area, eliminates the need for an external current-sense amplifier, and provides software-readable fault diagnostics via the IN pin behavior. Designers can use it to switch downstream subsystems such as sensor clusters, USB ports, and infotainment auxiliaries, where a 350 mA budget is sufficient and where fault isolation improves system reliability.
Recommended
Recommended Products Summary
Engineering reference data for BTS3800SLHTSA1 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | BTS3800SL | BTS452TATMA1 | BTS4140NHUMA1 | BTS3028SDLATMA1 | BTS3134NHUMA1 |
|---|---|---|---|---|---|---|
| Package | PG-SCT595-5-1 | PG-SCT595-5-1 - same | PG-TO252-5 (DPAK-5) | PG-TO252-5 (DPAK-5) | PG-TO252-5 (DPAK-5) | PG-TO252-5 (DPAK-5) |
| Brand | Infineon Technologies | Infineon Technologies | Infineon Technologies | Infineon Technologies | Infineon Technologies | Infineon Technologies |
| Continuous Load Current | 0.35 A | 0.35 A | 1.8 A | 1.4 A | 5 A | 0.5 A |
| On-Resistance R_DS(on) (typ.) | 0.8 Ω | 0.8 Ω | 0.06 Ω | 0.1 Ω | 0.028 Ω | 0.5 Ω |
| Drain-Source V_DS (max) | 41 V | 41 V | 41 V | 42 V | 42 V | 42 V |
| Switch Topology | Low-side | Low-side | High-side (PROFET) | Low-side | Low-side | Low-side |
| AEC-Q100 Qualification | Yes | Yes | Yes | Yes | Yes | Yes |
| Embedded Protections | OT, OCL, OV clamp, ESD | OT, OCL, OV clamp, ESD | OT, OCL, OV clamp, ESD, diagnostic | OT, OCL, OV clamp, ESD | OT, OCL, OV clamp, ESD | OT, OCL, OV clamp, ESD |
| Approx. Unit Price (1k qty, USD) | 0.37 | 0.37 | 0.55 | 0.45 | 0.65 | 0.40 |
Key Differentiators
- Single same-package drop-in availability (vs BTS3800SL)
- Lowerest on-resistance in PG-SCT595 footprint (vs Other PG-SCT595-class HITFETs)
- 41 V drain voltage margin for load-dump (vs Generic 30 V logic-level N-MOSFETs)
Design Notes
Estimated: at IOUT = 350 mA, V_battery = 12 V, R_DS(on) = 0.8 Ω, steady-state dissipation is P = I² × R = 0.098 W. The PG-SCT595-5 package has a typical R_thJA around 150 °C/W on a 2-layer 1 oz JEDEC test board, so the junction temperature rise is roughly 15 °C above ambient, well within the 150 °C Tj maximum. For best margin, increase the drain copper pad to at least 50 mm², which lowers R_thJA by about 30 % and provides headroom for sticky-relay fault conditions where dissipation briefly rises toward the current-limit foldback point.
Pin 5 / thermal pad of the BTS3800SLHTSA1 should be soldered to the PCB copper pour on the top layer for heat spreading. Use a 0.1 mm via array on the thermal pad to stitch heat to the bottom layer and inner ground planes. Place a 100 nF decoupling capacitor close to the VS / sense pin (Pin 4) to suppress high-frequency noise, and keep the high-current drain trace on Pin 3 wide (>0.5 mm/A) to avoid resistive drops that confuse the overcurrent protection threshold.
For inductive loads (relay coils, solenoids, small motors), add a flyback diode from the drain (Pin 3) directly to the supply rail as close to the BTS3800SLHTSA1 as possible. Without the diode, the demagnetization energy circulates through the device's internal overvoltage clamp, generating repetitive thermal stress that accelerates aging. Reverse-engineers often skip this diode in cost-down revs and then see field failures - we recommend a Schottky (e.g. SR20200CT, MBRS2040) with reverse voltage ≥ 40 V and forward current ≥ 1 A.
The IN pin (Pin 1) is a high-impedance CMOS input. Drive it from a clean MCU GPIO or an open-drain buffer; do not leave it floating in noisy automotive environments, as coupling onto a floating IN can accidentally enable the output. If using a 3.3 V MCU, the IN pin accepts logic levels up to 5.5 V, so no level shifter is needed. For PWM dimming of LEDs, the input slew rate should be at least 1 V/µs to avoid partial-turn-on glitches in the internal gate driver.
Compliance Information
AEC-Q100 automotive qualified per Infineon datasheet. RoHS and halogen-free compliance confirmed on Infineon product page for BTS3800SL family.
