The LM3481 device is a versatile Low-Side N-FET high-performance controller for switching regulators. The device is suitable for use in topologies requiring a low-side FET, such as boost, flyback, SEPIC, and so on. The LM3481 device can be operated at extremely high switching frequencies to reduce the overall solution size. The switching frequency of the LM3481 device can be adjusted to any value between 100kHz and 1MHz by using a single external resistor or by synchronizing it to an external clock. Current mode control provides superior bandwidth and transient response in addition to cycle-by-cycle current limiting. Current limit can be programmed with a single external resistor.
The LM3481 device has built-in protection features such as thermal shutdown, short-circuit protection and overvoltage protection. Power-saving shutdown mode reduces the total supply current to 5 µA and allows power supply sequencing. Internal soft-start limits the inrush current at start-up.
Part number | Order | Vin (Min) (V) | Vin (Max) (V) | Vout (Min) (V) | Vout (Max) (V) | Regulated outputs (#) | Switching frequency (Min) (kHz) | Switching frequency (Max) (kHz) | Iq (Typ) (mA) | Features | Duty cycle (Max) (%) | Operating temperature range (C) | Rating | Type | Package Group |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
LM3481-Q1 |
|
2.97 | 48 | 1.275 | 500 | 1 | 100 | 1000 | 3.7 |
Adjustable Current Limit
Enable Frequency Synchronization Light Load Efficiency Pre-Bias Start-Up UVLO Adjustable |
85 | -40 to 125 | Automotive | Controller | VSSOP | 10 |
LM25122-Q1 |
|
3 | 42 | 3 | 50 | 1 | 50 | 600 | 4 |
Enable
Frequency Synchronization Phase Interleaving Synchronous Rectification |
100 | -40 to 125 | Automotive | Controller | HTSSOP | 20 |
LM3478 |
|
2.97 | 40 | 1.26 | 500 | 1 | 100 | 1000 | 2.7 |
Adjustable Current Limit
Enable Frequency Synchronization Light Load Efficiency Pre-Bias Start-Up |
100 | -40 to 125 | Catalog | Controller |
SOIC | 8
VSSOP | 8 |
LM3488 |
|
2.97 | 40 | 1.26 | 500 | 1 | 100 | 1000 | 2.7 |
Adjustable Current Limit
Enable Frequency Synchronization Light Load Efficiency Pre-Bias Start-Up |
100 | -40 to 125 | Catalog | Controller | VSSOP | 8 |
LM5022-Q1 |
|
3 | 60 | 1.25 | 300 | 1 | 170 | 2200 | 3.5 |
Enable
Frequency Synchronization UVLO Adjustable |
90 | -40 to 125 | Automotive | Controller | VSSOP | 10 |
LM5122-Q1 |
|
3 | 65 | 3 | 100 | 1 |