| Number of channels (#) | 1 |
| Topology | Boost Controller, Buck-Boost Controller, Sepic Controller |
| Rating | Automotive |
| Operating temperature range (C) | -40 to 125, -40 to 150 |
| | |
| Vin (Min) (V) | 4.5 |
| Vin (Max) (V) | 75 |
| Vout (Min) (V) | 3 |
| Vout (Max) (V) | 72 |
| Iout (Max) (A) | 5 |
| Iq (Typ) (mA) | 2 |
| Switching frequency (Max) (kHz) | 2000 |
| Features | Adjustable Switch Frequency, Enable/Shutdown, Thermal Shutdown |
- AEC Qualified for Automotive Applications
- Device Temperature Grade 1: ?40°C ≤ TA ≤ 125°C (LM3421-Q1 and LM3423-Q1)
- Device Temperature Grade 0: ?40°C ≤ TA ≤ 150°C (LM3421-Q0 and LM3423-Q0)
- VIN Range From 4.5 V to 75 V
- High-Side Adjustable Current Sense
- 2-?, 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-Q1 and LM3423-Q0 Only)
- Fault Status Flag and Timer(LM3423-Q1 and LM3423-Q0 Only)
The LM3421-Q1 and LM3423-Q1 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-Q1 and LM3423-Q1 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-Q1 and LM3423-Q1 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.
