Electronic water pump — key device selection
Engineering problem
A BLDC water pump runs continuously next to a hot engine: the power stage must survive load dump and inductive spikes, start reliably at low temperature, and keep conduction losses low enough to avoid derating in a sealed housing.
System block diagram
Block list (text version)
- Input protection TVS diode / ESD protection
- Control Automotive MCU
- Gate drive Gate driver IC
- Power stage Automotive MOSFET
- Motor BLDC motor (load)
- Sensing Current-sense amplifier / op-amp
Input protection
Why this device： The pump sits on the same rail as solenoids and motors; load dump and inductive switching reach tens of volts above nominal.
How to choose： Choose VRWM above jump-start voltage and a clamping voltage below the absolute maximum of the following stage; check ISO 7637-2 pulse 1/2a/3 and pulse 5 ratings.
| Part number | Brand | Category | Package | Qualification | Operating temperature | Key parameters | Docs | Actions |
|---|---|---|---|---|---|---|---|---|
| 1SMB30CAT3G In stock | onsemi | TVS Diodes | SMB | AEC-Q101 qualified | -55 °C ~ +150 °C | vrwm: 30 V · ppp: 600 W · direction: Uni-directional | Datasheet ↗ | |
| 1.5KE24CA-TP | MCC | Transient Voltage Suppressor | — | Qualification to be verified | To be confirmed | To be confirmed | Datasheet ↗ | |
| 1.5KE250A-TP In stock | MCC | TVS Diodes | DO-201AE | Qualification to be verified | To be confirmed | To be confirmed | Datasheet ↗ | |
| 1.5KE480A | WAYON | Transient Voltage Suppressor | — | Qualification to be verified | To be confirmed | To be confirmed | Datasheet ↗ | |
| 1.5SMC33CA | LITTLEFUSE | Transient Voltage Suppressor | — | Qualification to be verified | To be confirmed | To be confirmed | Datasheet ↗ | |
| 1.5SMC6.8CA In stock | Littelfuse | TVS Diodes | SMC | Qualification to be verified | To be confirmed | To be confirmed | To be confirmed |
Control
Why this device： Runs sensorless or Hall-based commutation, PWM generation, diagnostics and LIN/CAN communication with the engine ECU.
How to choose： Timer resolution and PWM frequency headroom first, then flash for diagnostics and calibration, then the temperature grade required by the mounting location.
| Part number | Brand | Category | Package | Qualification | Operating temperature | Key parameters | Docs | Actions |
|---|---|---|---|---|---|---|---|---|
| MKE04Z8VWJ4 In stock | NXP | Microcontrollers (MCU) | SOIC-20 | AEC-Q100 Grade 1 qualified | -40 °C ~ +125 °C | core: Arm Cortex-M0+ · freq: 48 MHz · flash: 8 KB | Datasheet ↗ | |
| ATMEGA32A-AU In stock | Microchip | Microcontrollers (MCU) | TQFP-44 | Qualification to be verified | To be confirmed | To be confirmed | Datasheet ↗ | |
| ATSAM4S2AA-MU In stock | Microchip | Microcontrollers (MCU) | QFN-48 | Qualification to be verified | To be confirmed | To be confirmed | Datasheet ↗ | |
| BS83A01C In stock | Holtek | Microcontrollers (MCU) | SOT-23-6 | Qualification to be verified | To be confirmed | To be confirmed | Datasheet ↗ | |
| HT66F002/MSOP10 In stock | Holtek | Microcontrollers (MCU) | MSOP-10 | Qualification to be verified | To be confirmed | To be confirmed | Datasheet ↗ | |
| MM32F0010A1N In stock | MindMotion | MCU (Value Line) | QFN-20 | Qualification to be verified | To be confirmed | To be confirmed | Datasheet ↗ |
Sensing
Why this device： Phase current is needed for commutation, over-current protection and fault logging — Hall or shunt based.
How to choose： Pick the shunt value from the maximum current and allowed dissipation, then the amplifier gain and offset drift at the highest junction temperature.
| Part number | Brand | Category | Package | Qualification | Operating temperature | Key parameters | Docs | Actions |
|---|---|---|---|---|---|---|---|---|
| INA199B2QDCKRQ1 In stock | TI | Amplifiers & Linear | SOT-SC70-6 | AEC-Q100 Grade 1 qualified | -40 °C ~ +125 °C | supply: 2.7 ~ 26 V · channel: 1 · bw: 105 kHz | Datasheet ↗ | |
| LM2901MX/NOPB In stock | TI | Amplifiers & Linear | SOIC-14 | AEC-Q100 Grade 1 qualified | -40 °C ~ +125 °C | channel: 4 · bw: 1.3 MHz · vos: ±2 mV | Datasheet ↗ | |
| ACE358MTR-E1 In stock | ACE | Operational Amplifiers | SOP-8 | Qualification to be verified | To be confirmed | To be confirmed | Datasheet ↗ | |
| AD822ARZ-REEL7 In stock | ADI | Operational Amplifiers | SOIC-8 | Qualification to be verified | To be confirmed | To be confirmed | Datasheet ↗ | |
| LM258DR2G In stock | onsemi | Operational Amplifiers (Op-Amp) | SOIC-8 | Qualification to be verified | To be confirmed | To be confirmed | Datasheet ↗ | |
| LM2903XK In stock | Runic | Comparators | SOT-23-5 | Qualification to be verified | To be confirmed | To be confirmed | Datasheet ↗ |
Gate drive
Why this device： Three-phase bridges need three high-side drivers with bootstrap supply, dead-time control and fault reporting.
How to choose： Size peak current from Qg and target rise/fall time; confirm UVLO thresholds, Miller clamp and whether the bootstrap can hold at your maximum duty.
| Part number | Brand | Category | Package | Qualification | Operating temperature | Key parameters | Docs | Actions |
|---|---|---|---|---|---|---|---|---|
| FAN3224TMX In stock | onsemi | Gate Drivers | SOIC-8 | AEC-Q100 Grade 1 qualified | -40 °C ~ +125 °C | channel: 2 · current: 4 A · voltage: 18 V | Datasheet ↗ | |
| CFG2211S Available to order | Chipflow | Gate Drivers | SOP8 | Qualification to be verified | To be confirmed | To be confirmed | To be confirmed | |
| CFG2216M Available to order | Chipflow | Gate Drivers | MSOP10 | Qualification to be verified | To be confirmed | To be confirmed | To be confirmed | |
| CFG2241S Available to order | Chipflow | Gate Drivers | SOP8 | Qualification to be verified | To be confirmed | To be confirmed | To be confirmed | |
| CFG2242D Available to order | Chipflow | Gate Drivers | DFN10-3x3 | Qualification to be verified | To be confirmed | To be confirmed | To be confirmed | |
| CFG2246S Available to order | Chipflow | Gate Drivers | SOP8 | Qualification to be verified | To be confirmed | To be confirmed | To be confirmed |
Power stage
Why this device： Six devices switch the motor current; conduction loss sets the housing temperature and switching loss sets the EMI profile.
How to choose： Voltage margin first (60–80 V for 12 V systems), then RDS(on) at 150 °C, then pulse current at start-up and avalanche energy during blocking.
| Part number | Brand | Category | Package | Qualification | Operating temperature | Key parameters | Docs | Actions |
|---|---|---|---|---|---|---|---|---|
| BSC026N02KSGAUMA1 In stock | Infineon | OptiMOS Low-Voltage MOSFETs | SC026 | AEC-Q101 qualified | -55 °C ~ +150 °C | channel: N · vds: 25 V · id: 100 A | Datasheet ↗ | |
| 2N7002-TP In stock | MCC | Small-Signal MOSFETs | SOT-23 | Qualification to be verified | To be confirmed | To be confirmed | Datasheet ↗ | |
| 2N7002DW-TP In stock | MCC | Small-Signal MOSFETs | SOT-363 | Qualification to be verified | To be confirmed | To be confirmed | Datasheet ↗ | |
| 2N7002E-7-F In stock | Diodes | Small-Signal N-Channel MOSFETs | SOT-23 | Qualification to be verified | To be confirmed | To be confirmed | Datasheet ↗ | |
| 2N7002K-TP In stock | MCC | Small-Signal MOSFETs | SOT-23 | Qualification to be verified | To be confirmed | To be confirmed | Datasheet ↗ | |
| 2N7002KDQ-TP In stock | MCC | Small-Signal MOSFETs | SOT-23 | Qualification to be verified | To be confirmed | To be confirmed | Datasheet ↗ |
Key selection parameters
| System voltage | 12 V (9–16 V, jump start up to 26 V) |
| Peak / continuous current | Start-up and blocked-rotor current, not nominal |
| Motor power | Typically 30–200 W for coolant pumps |
| PWM frequency | 10–25 kHz for audible noise and EMI balance |
| Ambient / housing temperature | Under-hood up to 105–125 °C ambient |
| Qualification | AEC-Q100 Grade 1 / AEC-Q101 |
FAQ
Can I reuse an industrial MOSFET if the ratings look similar?
Ratings on paper are not the whole story: automotive parts add qualification testing, temperature-range guarantees and change-control commitments that industrial parts do not carry.
How is the pump project information used?
We record the application source with the request, so you do not have to re-explain the project; it is only used for this inquiry.
What if the exact part is not in your catalogue?
Send the part number — we check availability and pin-compatible alternatives against the original datasheet.
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Project inquiry
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