The SG1842/43 family of control IC's provides all the necessary features to implement off-line fixed frequency, current-mode switching power supplies with a minimum number of external components. Current-mode architecture demonstrates improved line regulation, improved load regulation, pulse-by-pulse current limiting and inherent protection of the power supply output switch. The band-gap reference is trimmed to ±1% over temperature. Oscillator discharge current is trimmed to less than ±10%. The SG1842/43 has under-voltage lockout, current limiting circuitry and start-up current of less than 1mA. The totem-pole output is optimized to drive the gate of a power MOSFET. The output is low in the off state to provide direct interface to an N-channel device. The SG1842/43 is specified for operation over the full military ambient temperature range of -55°C to 125°C. The SG2842/43 is specified for the industrial range of -25°C to 85°C, and the SG3842/43 is designed for the commercial range of 0°C to 70°C.
Additional Features
Optimized For Off-Line Control
Low Start-Up Current (<1mA)
Automatic Feed Forward Compensation
Trimmed Oscillator Discharge Current
Pulse-By-Pulse Current Limiting
Enhanced Load Response Characteristics
Under-Voltage Lockout with 6V Hysteresis (SG1842only)
Double-Pulse Suppression
High-Current Totem-Pole Output (1A Peak)
Internally Trimmed Band-gap Reference
500kHz Operation Under-voltage Lockout: SG1842 - 16 volts, SG1843 - 8.4 volts
Low Shoot-Through Current <75mA Over Temperature
The SG1842/43 family of control IC's provides all the necessary features to implement off-line fixed frequency, current-mode switching power supplies with a minimum number of external components.
Current-mode architecture demonstrates improved line regulation, improved load regulation, pulse-by-pulse current limiting and inherent protection of the power supply output switch. The band-gap reference is trimmed to ±1% over temperature.
Oscillator discharge current is trimmed to less than ±10%. The SG1842/43 has under-voltage lockout, current limiting circuitry and start-up current of less than 1mA. The totem-pole output is optimized to drive the gate of a power MOSFET. The output is low in the off state to provide direct interface to an N-channel device. The SG1842/43 is specified for operation over the full military ambient temperature range of -55°C to 125°C. The SG2842/43 is specified for the industrial range of -25°C to 85°C, and the SG3842/43 is designed for the commercial range of 0°C to 70°C.
Additional Features
- Optimized For Off-Line Control
- Low Start-Up Current (<1mA)
- Automatic Feed Forward Compensation
- Trimmed Oscillator Discharge Current
- Pulse-By-Pulse Current Limiting
- Enhanced Load Response Characteristics
- Under-Voltage Lockout with 6V Hysteresis (SG1842only)
- Double-Pulse Suppression
- High-Current Totem-Pole Output (1A Peak)
- Internally Trimmed Band-gap Reference
- 500kHz Operation Under-voltage Lockout: SG1842 - 16 volts, SG1843 - 8.4 volts
- Low Shoot-Through Current <75mA Over Temperature
