Overview
The LM5021MM-2/NOPB is a high-performance AC-DC current-mode PWM controller manufactured by Texas Instruments. This IC is designed for use in single-ended flyback and forward power converter configurations, offering robust features for efficient and reliable power management. It features a low start-up current of 25 µA, minimizing power losses, and includes various protection mechanisms such as under-voltage lockout, cycle-by-cycle current limiting, and hiccup mode for continuous overload protection. The controller also supports soft-start capabilities and has a 1-MHz capable oscillator that can be easily programmed with a single resistor. Its quick propagation delays and skip cycle mode enhance efficiency, especially at light load conditions.
Key Specifications
| Specification | Value |
|---|---|
| Manufacturer | Texas Instruments |
| Part Number | LM5021MM-2/NOPB |
| Power Supply Controller Type | Single Ended Controller |
| No. of Channels | 1 |
| Control Mode | Current Mode Control |
| Supply Voltage Min | 8 V |
| Supply Voltage Max | 30 V |
| IC Case / Package | VSSOP-8 |
| No. of Pins | 8 |
| IC Mounting | Surface Mount |
| Switching Frequency Typ | 500 kHz |
| Duty Cycle Max | 50% |
| Operating Temperature Min | -40°C |
| Operating Temperature Max | 125°C |
| Topology | Flyback, Forward |
| Output Current | 700 mA |
| Output Voltage | 8.5 V |
Key Features
- Fully compliant to industry standards
- Robust design for electrostatic discharge protection
- Wide operating temperature range of -40°C to 125°C
- Ultra-low start-up current of 25 µA to minimize power losses
- Under-voltage lockout, cycle-by-cycle current limiting, and hiccup mode for continuous overload protection
- Soft-start capabilities to reduce start-up stresses and current surges
- 1-MHz capable oscillator programmable with a single resistor
- Skip cycle mode to reduce input power and increase efficiency at light load conditions
- Direct opto-coupler interface and slope compensation (LM5021-1 only)
- Leading edge blanking of current sense signal and internal 0.7-A peak gate driver
Applications
The LM5021MM-2/NOPB is suitable for a variety of power management applications, including:
- Single-ended flyback and forward power converter configurations
- Offline power supplies
- DC-DC converters requiring high efficiency and reliability
- Industrial and consumer electronics where robust power management is essential
Q & A
- What is the typical switching frequency of the LM5021MM-2/NOPB?
The typical switching frequency is 500 kHz, but it can be programmed up to 1 MHz using a single resistor connected to the RT pin.
- What is the maximum duty cycle for the LM5021MM-2/NOPB?
The maximum duty cycle for the LM5021MM-2/NOPB is 50%.
- What protection mechanisms are included in the LM5021MM-2/NOPB?
The IC includes under-voltage lockout, cycle-by-cycle current limiting, and hiccup mode for continuous overload protection.
- How is the oscillator frequency programmed in the LM5021MM-2/NOPB?
The oscillator frequency is programmed using a single resistor connected from the RT pin to GND.
- What is the operating temperature range of the LM5021MM-2/NOPB?
The operating temperature range is -40°C to 125°C.
- Does the LM5021MM-2/NOPB support soft-start capabilities?
- What is the package type of the LM5021MM-2/NOPB?
The package type is VSSOP-8).
- Is the LM5021MM-2/NOPB RoHS compliant?
- What is the maximum output current of the LM5021MM-2/NOPB?
The maximum output current is 700 mA).
- Can the switching frequency of the LM5021MM-2/NOPB be synchronized to an external clock source?
