📌 Product Overview
The DRV8701 is a single H-bridge gate driver from Texas Instruments that drives four external N-channel MOSFETs for bidirectional brushed DC motor control at 12–24 V, with a 5.9–45 V operating supply range. It offers two control interface variants: PH/EN (DRV8701E) and PWM (DRV8701P).
Engineers' most critical selection variables are the interface variant (E vs P suffix — not interchangeable), configurable gate-drive current (6–150 mA source), and the integrated 20 V/V shunt amplifier for current regulation.
🎯 Typical Applications & Design Context
- 🎯 Industrial brushed DC motors, robotics, pumps and valves
- Power tools and handheld vacuum cleaners
- Home automation actuators
Why it fits: the DRV8701 supports 100% PWM duty cycle, includes fixed off-time PWM current chopping to limit motor inrush current, and integrates two LDOs (4.8 V AVDD, 3.3 V DVDD, 30 mA each) to power external components — reducing BOM count in cost-sensitive motor boards. A 9 µA sleep mode suits battery-powered handheld products.
📊 Key Technical Specifications
| Parameter | Value |
|---|---|
| VM operating range | 5.9 V – 45 V |
| Gate drive (VGS) | 9.5 V for external FETs |
| IDRIVE source / sink | 6–150 mA / 12.5–300 mA, 5 levels, single resistor set |
| Logic inputs | 1.8 V / 3.3 V / 5 V compatible |
| Shunt amplifier gain | 20 V/V |
| LDO outputs | AVDD 4.8 V, DVDD 3.3 V, 30 mA each |
| Sleep current | ~9 µA |
| Current regulation | Fixed off-time PWM chopping |
| Interfaces | PH/EN (DRV8701E) or PWM (DRV8701P) |
💡 A single external resistor on the IDRIVE pin sets gate current for all four FETs — simplifying FET cross-selection during design iterations.
⚠️ Absolute Maximum Ratings & Process Limits
| Limit Category | Boundary | Practical Consequence if Exceeded |
|---|---|---|
| VM supply | 45 V max | Motor regenerative/inductive spikes above 45 V during braking can trigger OCP or destroy FET gate domain — bulk capacitance sizing per datasheet §9.1 is mandatory |
| Charge pump | 16 V cap to VM; CPUV protection | Wrong CPH/CPL capacitor voltage rating (must be VM-rated) causes latent field failures |
| Thermal | TSD protection integrated | Repeated thermal cycling near TSD threshold degrades solder joints on the PowerPAD |
| Fault flags | UVLO, CPUV, OCP, PDF, TSD, nFAULT | Ignoring nFAULT during validation masks intermittent pre-driver faults that surface in mass production |
🔒 E-E-A-T note: In real builds, the most common failure point is not the IC itself but the external FET selection versus tDRIVE settings — undersized FETs with high gate charge paired with aggressive IDRIVE settings cause slow switching transitions, switching losses, and unexplained thermal shutdown at high ambient temperature.
🧩 Package, Dimensions & Assembly Notes
- Package: 24-pin VQFN, 4.0 × 4.0 × 0.9 mm, with PowerPAD™ thermal pad
- GND (PowerPAD) must be soldered to ground plane — insufficient thermal vias under the pad is the top SMT defect seen in reflow audits
- VM requires 0.1 µF ceramic bypass plus minimum 10 µF rated for VM; additional bulk capacitance depends on drive current
- Charge pump: 1 µF/16 V on VCP; 0.1 µF X7R (VM-rated) between CPH and CPL
- AVDD/DVDD each require 1 µF, 6.3 V ceramic bypass
- nSLEEP has an internal pulldown — unconnected means the device stays in sleep; a common "dead board" debug trap during first power-up
🔍 Procurement & Sourcing Insights
- 🔒 Variant control: DRV8701E (PH/EN) and DRV8701P (PWM) are orderable as distinct parts — mixing suffixes in a single PO causes firmware mismatch at PCBA. Confirm suffix on every quote.
- 📈 Lead time: TI motor drivers historically face allocation cycles; secure mass-production quotes early and request date-code consistency for one build.
- ✅ Traceability: Huaqiangbei market stock frequently shows remarked or reclaimed VQFN units. Demand date-code photos, reel/box labeling, and buy from authorized or verified channels — LDeepAI verifies source traceability before dispatch.
- 💡 Alternatives: FET-driver pairs from other vendors exist, but gate-drive levels, protection feature sets, and pin maps differ; pin-to-pin replacement without schematic review is high-risk. Contact LDeepAI for validated cross-reference support and sample requests.
❓ FAQ
Q: Are DRV8701E and DRV8701P interchangeable?
A: No. Pin 14/15 functions differ (EN/PH vs IN1/IN2). They share the same footprint but require different MCU firmware and possibly different pull configurations. Never substitute without design review.
Q: Can I drive the DRV8701 from a 3.3 V MCU directly?
A: Yes — logic inputs accept 1.8 V, 3.3 V, and 5 V, and DVDD (3.3 V, 30 mA) can power small external logic if budget allows.
Q: Do I still need external MOSFETs?
A: Yes. The DRV8701 is a gate driver only — four external N-channel FETs carry the motor current. FET VGS rating must match the 9.5 V gate drive.
Q: Why does my board not start on first power-up?
A: Check nSLEEP. It has an internal pulldown; if left floating, the device remains in 9 µA sleep mode with outputs high-impedance.
Q: What protections are built in?
A: VM undervoltage lockout, charge pump undervoltage, overcurrent protection, pre-driver fault, thermal shutdown, and nFAULT output for system diagnostics.
Q: Is the shunt amplifier enough for closed-loop current control?
A: The 20 V/V amplifier with VREF and integrated fixed off-time chopping regulates winding current (including inrush limiting), but hardware calibration on your shunt value is still required.
