Technical Analysis of L6202 Chip:
1. One-Sentence Description
L6202 is a DMOS full-bridge motor driver chip using Multipower-BCD technology, supporting 48V power supply and 1.5A continuous current output, integrating thermal protection and cross-conduction prevention, specially designed for efficient motor control.
2. Features
- High voltage support: Maximum operating voltage 48V (absolute maximum 52V)
- Current capability: 5A peak current, 1.5A continuous RMS current
- Low on-resistance: RDS(ON) typical value 0.3Ω (25°C)
- High-frequency operation: Supports 100kHz switching frequency
- Integrated protection: Thermal shutdown (triggered at 150°C), dead time protection (>40ns)
- Compatibility: TTL/CMOS/μC compatible logic inputs
- Energy efficiency optimization: Internal charge pump drives upper bridge arm, requiring external bootstrap capacitor
3. Core Technical Specifications
| Parameter | Value | Condition |
|---|---|---|
| Supply voltage Vs | 12-48V | Operating range |
| Reference voltage Vref | 13.5V | IREF=2mA |
| Quiescent current Is | 10mA (typical) | EN=H, VIN=L |
| Thermal resistance Rth j-amb | 60°C/W (maximum) | Without heat sink |
| Dead time Td | 100ns (typical) | Anti-cross conduction |
| Operating temperature Tj | -40 to +150°C | Storage/junction temperature |
4. The Story Behind the Chip
Technological revolution: Launched by STMicroelectronics in 2003 (document date July 2003), it commercialized Multipower-BCD technology for the first time. This technology breakthrough integrates DMOS power transistors with CMOS/bipolar circuits, eliminating the need for external MOS driver components, greatly simplifying motor control system design, and becoming a milestone in industrial driver chips.
5. Design Philosophy
Trinity optimization:
- Power stage: DMOS transistors achieve low RDS(ON) (0.3Ω) and high-speed switching
- Control logic: Independent half-bridge control (IN1/IN2) and global enable (ENABLE)
- System integration: Built-in charge pump drives the upper bridge arm, which can work by connecting an external capacitor through the BOOT pin, significantly reducing the number of external components.
6. Application Scenarios
- DC motors: Bidirectional speed control (with L6506 current regulator)
- Stepper motors: Two-phase bipolar motor driving (with L297/L6506 controller)
- Typical scenarios: Printer paper feed motors, robot joint drives, industrial automation valve control
7. Unique Advantages
Dynamic current management: Real-time monitoring of motor current through an external resistor on the SENSE pin, combined with internal dead time protection, completely eliminates the risk of bridge arm shoot-through. Compared with competitors of the same period, its dual protection design of cross-conduction prevention and thermal shutdown (Section 2 of the document) ensures system robustness at high switching frequencies (100kHz).
8. Key Considerations for Engineers in Selection
- Voltage margin: Continuous operating voltage ≤48V, transient tolerance 52V (absolute maximum)
- Heat dissipation design:
- Maximum power consumption 1.3W without heat sink (70°C environment)
- PCB copper foil heat dissipation required (Document Figure 23): 10cm² double-sided copper layer can reduce thermal resistance to 40°C/W
- Key peripherals:
- Bootstrap capacitor ≥10nF (BOOT1/BOOT2 pins)
- Vref pin requires 0.22μF bypass capacitor
- Output must be configured with RC snubber network (formula: R≈Vs/Ip, C=Ip/(dV/dt))
- Disabled scenario: Full bridge turns off when ENABLE=low, preferred solution for emergency braking
