Packaging information
| Package | Pins HTSSOP (PWP) | 16 |
| Operating temperature range (°C) -40 to 125 |
| Package qty | Carrier 92 | TUBE |
Features for the LM3421
- VIN Range From 4.5 V to 75 V
- High-Side Adjustable Current Sense
- 2-Ω, 1-A Peak MOSFET Gate Driver
- Input Undervoltage and Output Overvoltage Protection
- PWM and Analog Dimming
- Cycle-by-Cycle Current Limit
- Programmable Switching Frequency
- Zero Current Shutdown and Thermal Shutdown
- LED Output Status Flag (LM3423 and LM3423-Q0 Only)
- Fault Status Flag and Timer(LM3423 and LM3423-Q0 Only)
Description for the LM3421
The LM3421 and LM3423 family of devices are versatile high voltage N-channel MOSFET controllers for LED drivers. They can be easily configured in buck, boost, buck-boost and SEPIC topologies. This flexibility, along with an input voltage rating of 75 V, makes the these controllers ideal for illuminating LEDs in a large family of applications.
Adjustable high-side current sense voltage allows for tight regulation of the LED current with the highest efficiency possible. The LM3421 and LM3423 devices use predictive off-time (PRO) control, which is a combination of peak current-mode control and a predictive off-timer. This method of control eases the design of loop compensation while providing inherent input voltage feed-forward compensation.
The LM3421 and LM3423 devices include a high-voltage start-up regulator that operates over a wide input range of 4.5 V to 75 V. The internal PWM controller is designed for adjustable switching frequencies of up to 2 MHz, thus enabling compact solutions.