1 LT1424-9 SN14249 14249FS 9V output isolated flyback switching regulator, no transformer "third winding" or opto-isolator required, application circuit meets PCMCIA Type II height requirement, fixed, application specific 9V output voltage, regulation maintained well into discontinuous mode (light load), load compensation provides excellent load regulation, available in 8-pin PDIP and SO packages, operating frequency: 285kHz. The LT ®1424-9 is a monolithic high power switching regulator specifically designed for the isolated flyback topology. No "third winding" or opto-isolator is required; the integrated circuit senses the isolated output voltage directly from the primary side flyback waveform. A high current, high efficiency switch is included on the die along with all oscillator, control and protection circuitry. The LT1424-9 operates with input supply voltages from 3V to 20V and draws only 7mA quiescent current. It can deliver up to 200mA at 9V with no external power devices. By utilizing current mode switching techniques, it pro- vides excellent AC and DC line regulation. The LT1424-9 has a number of features not found on other switching regulator ICs. Its unique control circuitry can maintain regulation well into discontinuous mode. Load compensation circuitry allows for improved load regula- tion. An externally activated shutdown mode reduces total supply current to 20µA typical for standby operation. -9V PCMCIA Type II Isolated LAN Supply (2.41mm Maximum Height).
The LT1424-9 is a monolithic high‑power switching regulator designed for isolated flyback topologies. It provides a fixed 9 V output without the need for a third transformer winding or optoisolator, using an integrated feedback scheme that senses the primary side flyback waveform.
The device operates from 3 V to 20 V input, delivers up to 200 mA at 9 V, and includes features such as load compensation, shutdown mode (down to 15 pA), and a selectable 8‑pin PDIP or SQ package. Detailed electrical characteristics, pin functions, and typical application circuits are provided in the handbook.
| Operating Frequency | 285 kHz |
|---|---|
| Input Voltage Range | 3 V to 20 V |
| Quiescent Current | 7 mA |
| Maximum Output Current | 200 mA at 9 V |
| Shutdown Mode Supply Current | 15 pA – 40 pA |
| Switching Frequency Range | 260 kHz – 300 kHz |
It operates from 3 V up to 20 V input.
The regulator provides a fixed 9 V output.
The LT1424-9 draws about 7 mA of quiescent current.
No, it does not require a third winding or optoisolator.