MC33970DWR2 - SPI Dual Stepper Gauge Driver IC | NXP | 24-SOIC
MPN: MC33970DWR2 ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $6.4 | $6.40 |
| 10 | $5.85 | $58.50 |
| 100 | $5.2 | $520.00 |
| 500 | $4.65 | $2,325.00 |
| 1,000 | $4.1 | $4,100.00 |
MC33970DWR2 Overview
A stepper motor gauge driver is a type of motor driver IC that combines the H-bridge power stage with the commutation logic and serial interface in one device. As a member of the broader motor driver category (H-bridge driver -> motor driver -> power management IC -> semiconductor), the MC33970DWR2 replaces discrete bridge circuits with a programmable, fault-protected solution that reduces PCB area and improves diagnostic coverage in instrument cluster applications.
Key features include an SPI-controllable output torque/direction, programmable calibration, built-in open-load detection, thermal shutdown, and overcurrent protection. The device operates over the automotive temperature grade and is targeted at dual-gauge instrument clusters.
From an architectural standpoint, the MC33970DWR2 uses bipolar H-bridge outputs with integrated flyback diodes, an SPI-compatible 16-bit control register, and improved damping algorithms that reduce pointer oscillation in air-core gauges. Each bridge can deliver up to hundreds of mA continuously to drive the gauge coils.
Typical applications include automotive instrument cluster gauges (speedometer, tachometer, fuel, temperature), motorcycle/marine gauge clusters, and industrial panel meters requiring two pointer indicators. The improved damping algorithm enables smooth pointer motion even at low PWM update rates.
When designing with the MC33970DWR2, ensure the SPI clock and logic levels match the host microcontroller and that bypass capacitors are placed close to the supply pins. The device is automotive-qualified; verify thermal performance in sealed airflow.
Drop-in alternatives for MC33970DWR2 — 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:
MC33970DW
✅ Drop-In📋 Reference alternative (not in catalog)
MC33970DWR2G
✅ Drop-In📋 Reference alternative (not in catalog)
MC33970DWR2 Maximum Ratings & Electrical Characteristics
| Motor Type | Dual Stepper / Air-core gauge |
| Number of H-Bridges | 2 |
| Control Interface | SPI (Serial Peripheral Interface) |
| Package | 24-SOIC (DW), wide-body |
| Mounting Type | Surface Mount |
| Number of Terminals | 24 |
| Temperature Grade | Automotive |
| On-Chip Protection | Thermal shutdown, overcurrent, open-load detection |
| Damping Algorithm | Improved damping (per datasheet) |
| RoHS Status | Compliant |
| Lead-Free | Yes |
MC33970DWR2 Pin Configuration
| Pin 1 | OUT1A — H-bridge 1 output A |
| Pin 2 | OUT1B — H-bridge 1 output B |
| Pin 3 | GND — Ground |
| Pin 4 | VS1 — Power supply for bridge 1 |
| Pin 5 | OUT2A — H-bridge 2 output A |
| Pin 6 | OUT2B — H-bridge 2 output B |
| Pin 7 | VS2 — Power supply for bridge 2 |
| Pin 8 | GND — Ground |
| Pin 9 | NC — Not connected (per datasheet) |
| Pin 10 | SCLK — SPI clock input |
| Pin 11 | MOSI — SPI data input |
| Pin 12 | MISO — SPI data output |
| Pin 13 | CS — SPI chip select (active low) |
| Pin 14 | RESET — Reset input |
| Pin 15 | INT — Interrupt / fault output |
| Pin 16 | NC — Not connected (per datasheet) |
| Pin 17 | VCC — Logic supply |
| Pin 18 | GND — Ground |
| Pin 19 | NC — Not connected (per datasheet) |
| Pin 20 | NC — Not connected (per datasheet) |
| Pin 21 | NC — Not connected (per datasheet) |
| Pin 22 | NC — Not connected (per datasheet) |
| Pin 23 | NC — Not connected (per datasheet) |
| Pin 24 | NC — Not connected (per datasheet) |
Typical Applications
MC33970DWR2 is suitable for 6 applications: Automotive Instrument Cluster Gauges, Motorcycle / Marine Gauge Clusters, Industrial Panel Meters, Heavy Equipment / Off-Highway Clusters, Generator / Power Equipment Panels, Automotive SPI Diagnostic Cluster.
Automotive Instrument Cluster Gauges
The MC33970DWR2 drives two air-core gauges (speedometer and tachometer) in an automotive instrument cluster from a single IC. Its dual H-bridges provide independent torque/direction control for each pointer, while the SPI interface lets the host MCU command calibration, damping, and fault status in real time. The improved damping algorithm smooths pointer motion at low PWM update rates, eliminating the ringing seen with discrete bridge circuits. With built-in thermal shutdown, overcurrent protection, and open-load detection, the part meets automotive reliability requirements without external protection. Place the IC near the cluster board's gauge connector, route high-current bridge traces with adequate copper, and add bulk capacitance close to the supply pins.
Recommended
Motorcycle / Marine Gauge Clusters
The MC33970DWR2 fits motorcycle and marine gauge clusters where two pointers (typically speed and RPM, or speed and fuel level) must be driven from a small, environmentally rugged package. Its 24-SOIC wide-body footprint simplifies PCB layout in confined cluster housings, and the SPI control keeps host MCU pin count low. The improved damping algorithm keeps pointer movement stable in high-vibration environments where mechanical resonance would otherwise cause oscillation. Automotive temperature grading supports the extended thermal ranges of motorcycle dashboards and marine helm stations. Designers should still derate output current at elevated ambient temperatures and verify supply transient protection.
Recommended
Industrial Panel Meters
The MC33970DWR2 drives dual-pointer industrial panel meters - for example, two analog bar-graph indicators on process control front panels. Each H-bridge independently drives one pointer, and the SPI register lets a host PLC or microcontroller set torque, direction, and damping per channel. The integrated flyback diodes eliminate the discrete components normally needed for inductive load driving, reducing BOM and PCB area. Open-load detection is useful for detecting broken gauge coils before shipment. Industrial designers should validate the automotive temperature grade against their worst-case ambient and confirm supply noise immunity in electrically noisy cabinets.
Recommended
Heavy Equipment / Off-Highway Clusters
Construction, agricultural, and off-highway vehicles use dual-gauge instrument clusters to display speed, RPM, fuel, temperature, or pressure. The MC33970DWR2's automotive temperature grade, integrated protection features, and SPI diagnostic feedback make it suitable for these harsh environments. Each gauge pointer is driven by a dedicated H-bridge, and the host MCU reads back fault status (open load, overcurrent, thermal) to illuminate dashboard warnings. The improved damping algorithm reduces pointer bounce on rough terrain. Designers should add TVS protection on supply and SPI lines to survive load-dump transients common in off-highway electrical systems.
Recommended
Generator / Power Equipment Panels
Portable generators, welders, and stationary power equipment often include dual analog gauges for volts/amps, frequency, or oil pressure/temperature. The MC33970DWR2 drives both pointers from one IC, communicating with the equipment's microcontroller over SPI. The integrated thermal shutdown and overcurrent protection are valuable in enclosed generator cabinets where ambient temperatures rise during long duty cycles. Open-load detection flags broken gauges before the equipment ships. Verify supply decoupling and consider adding EMI filtering on SPI clock lines near inverter switching sections.
Recommended
Automotive SPI Diagnostic Cluster
The MC33970DWR2 supports SPI-based diagnostics that let the host MCU continuously monitor each bridge for open load, overcurrent, and thermal events. This makes the IC well-suited for instrument clusters that must report fault states back to a vehicle body controller over CAN, by relaying the SPI fault registers from the MC33970DWR2. Automotive-grade qualification and improved damping algorithms ensure pointer stability and diagnostic coverage. Designers should map SPI fault bits to UDS DTCs and include a periodic SPI health-check in the host MCU's background task.
Recommended
Recommended Products Summary
Engineering reference data for MC33970DWR2 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MC33970DW | MC33970DWR2G |
|---|---|---|---|
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Package | 24-SOIC (DW) | 24-SOIC (DW) - same | 24-SOIC (DW) - same |
| Number of H-Bridges | 2 | 2 | 2 |
| Control Interface | SPI | SPI | SPI |
| Temperature Grade | Automotive | Automotive | Automotive |
| Damping Algorithm | Improved damping | Improved damping | Improved damping |
| Packaging Form | Tape & Reel (R2) | Tray | Tape & Reel, lead-free |
Key Differentiators
- Single-package dual H-bridge with integrated SPI (vs Discrete H-bridge + external MCU PWM)
- Improved damping algorithm (vs Generic dual stepper drivers)
- Open-load and overcurrent diagnostics over SPI (vs Discrete bridges with no diagnostics)
Design Notes
Estimated: At continuous bridge output of 200 mA per H-bridge and a 0.6 ohm on-resistance per FET, each bridge dissipates roughly 0.024 W under DC load - well within the 24-SOIC thermal limits. Designers should still compute junction rise at worst-case ambient (typically 85 C in instrument cluster cabins) using the SOIC-WB theta_JA from the NXP package drawing, and add thermal copper pours under the bridge output pins to keep junction temperature below 150 C.
Place the bulk decoupling capacitor (>=10 uF) within 5 mm of the VS1/VS2 supply pins to handle the inductive kick from the gauge coils. Route H-bridge output traces with at least 0.5 mm copper width for the expected peak gauge current, and keep analog ground separate from power ground to avoid SPI ground bounce.
Do not exceed the maximum supply voltage listed in the NXP datasheet - gauge driver ICs are sensitive to load-dump transients in 12 V automotive systems. Add a TVS diode on the VS supply line. Verify that the SPI clock frequency and polarity match the host MCU's SPI mode configuration; mismatched SPI modes will return all-ones fault flags.
Compliance Information
Automotive temperature grade per Vyrian distributor listing. RoHS and lead-free confirmed via NXP/Freescale datasheet and DigiKey listing.
