Microchip Technology

The SG1844/45 family of control ICs provides all the required 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 Bandgap reference is trimmed to ±1% over temperature. Oscillator discharge current is trimmed to less than ±10%. The SG1844/45 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 Nchannel device. Both operate up to a maximum duty cycle range of zero to <50% due to an internal toggle flip-flop which blanks the output off every other clock cycle. The SG1844/45 is specified for operation over the full military ambient temperature range of -55°C to 125°C. The SG3844/45 is designed for the commercial range of 0°C to 70°C.

This monolithic voltage regulator is designed for use with either positive or negative supplies as a series, shunt, switching, or floating regulator with currents up to 150 mA. Higher current requirements may be accommodated through the use of external NPN or PNP power transistors. This device consists of a temperature compensated reference amplifier, error amplifier, power series pass transistor, current limit, and remote shutdown circuitry. The SG723 will operate over the full military ambient temperature range of -55°C to 125°C. **Microchip Ordering Part** [**Standard Microcircuit Drawing (SMD)**](https://ww1.microchip.com/downloads/en/DeviceDoc/00003952.pdf) SG723F-JAN Cross Reference M38510/10201BHA SG723F-JAN Cross Reference M38510/10201BHX SG723J-JAN Cross Reference M38510/10201BCA SG723J-JAN Cross Reference M38510/10201BCX SG723T-JAN Cross Reference M38510/10201BIA SG723T-JAN Cross Reference M38510/10201BIX

The SG78xxA/SG78xx series of positive regulators offer self-contained, fixed-voltage capability with up to 1.5 A of load current and input voltage up to 50 V (SG78xxA series only). These units feature a unique on-chip trimming system to set the output voltages to within ±1.5% of nominal on the SG78xxA series with ±2.0% on the SG78xx series. The SG78xxA versions also offer much improved line and load regulation characteristics. Utilizing an improved bandgap reference design, problems such as drift in output voltage and large changes in the line and load regulation, that are normally associated with the Zener diode references have been eliminated. All protective features of thermal shutdown, current limiting, and safe-area control have been designed into these units and since these regulators require only a small output capacitor for satisfactory performance, ease of application is assured. Although designed as fixed-voltage regulators, the output voltage can be increased through the use of a simple voltage divider. The low quiescent drain current of the device ensures good regulation when this method is used. Product is available in hermetically sealed TO-257 (both case grounded ‘G’ and isolated ‘IG’), TO-3, TO-39 and leadless chip carrier (LCC) packages. **Microchip Ordering Part** [**Standard Microcircuit Drawing (SMD)**](https://ww1.microchip.com/downloads/en/DeviceDoc/00003952.pdf) SG7805AG-DESC Cross Reference 5962-8778201TA SG7805AG-DESC Cross Reference 5962-8778201TX SG7805AIG-DESC Cross Reference 5962-8778201UA SG7805AIG-DESC Cross Reference 5962-8778201UX SG7805AK-DESC Cross Reference 5962-8778201YA SG7805AK-DESC Cross Reference 5962-8778201YX SG7805AL-DESC Cross Reference 5962-87782012A SG7805AL-DESC Cross Reference 5962-87782012X SG7805AT-DESC Cross Reference 5962-8778201XA SG7805AT-DESC Cross Reference 5962-8778201XX

The SG78xxA/SG78xx series of positive regulators offer self-contained, fixed-voltage capability with up to 1.5 A of load current and input voltage up to 50 V (SG78xxA series only). These units feature a unique on-chip trimming system to set the output voltages to within ±1.5% of nominal on the SG78xxA series with ±2.0% on the SG78xx series **Microchip Ordering Part** [**Standard Microcircuit Drawing (SMD)**](https://ww1.microchip.com/downloads/en/DeviceDoc/00003952.pdf) SG7808AIG-DESC Cross Reference 5962-8962801UA SG7808AIG-DESC Cross Reference 5962-8962801UX SG7808AK-DESC Cross Reference 5962-8962801YA SG7808AK-DESC Cross Reference 5962-8962801YX SG7808AT-DESC Cross Reference 5962-8962801XA SG7808AT-DESC Cross Reference 5962-8962801XX

The SG78xxA/SG78xx series of positive regulators offer self-contained, fixed-voltage capability with up to 1.5 A of load current and input voltage up to 50 V (SG78xxA series only). These units feature a unique on-chip trimming system to set the output voltages to within ±1.5% of nominal on the SG78xxA series with ±2.0% on the SG78xx series. The SG78xxA versions also offer much improved line and load regulation characteristics. Utilizing an improved bandgap reference design, problems such as drift in output voltage and large changes in the line and load regulation, that are normally associated with the Zener diode references have been eliminated. All protective features of thermal shutdown, current limiting, and safe-area control have been designed into these units and since these regulators require only a small output capacitor for satisfactory performance, ease of application is assured. Although designed as fixed-voltage regulators, the output voltage can be increased through the use of a simple voltage divider. The low quiescent drain current of the device ensures good regulation when this method is used. Product is available in hermetically sealed TO-257 (both case grounded ‘G’ and isolated ‘IG’), TO-3, TO-39 and leadless chip carrier (LCC) packages. **Microchip Ordering Part** [**Standard Microcircuit Drawing (SMD)**](https://ww1.microchip.com/downloads/en/DeviceDoc/00003952.pdf) SG7812AG-DESC Cross Reference 5962-8777601TA SG7812AG-DESC Cross Reference 5962-8777601TX SG7812AIG-DESC Cross Reference 5962-8777601UA SG7812AIG-DESC Cross Reference 5962-8777601UX SG7812AK-DESC Cross Reference 5962-8777601YA SG7812AK-DESC Cross Reference 5962-8777601YX SG7812AL-DESC Cross Reference 5962-87776012A SG7812AL-DESC Cross Reference 5962-87776012X SG7812AT-DESC Cross Reference 5962-8777601XA SG7812AT-DESC Cross Reference 5962-8777601XX

The SG78xxA/SG78xx series of positive regulators offer self-contained, fixed-voltage capability with up to 1.5 A of load current and input voltage up to 50 V (SG78xxA series only). These units feature a unique on-chip trimming system to set the output voltages to within ±1.5% of nominal on the SG78xxA series with ±2.0% on the SG78xx series. The SG78xxA versions also offer much improved line and load regulation characteristics. Utilizing an improved bandgap reference design, problems such as drift in output voltage and large changes in the line and load regulation, that are normally associated with the Zener diode references have been eliminated. All protective features of thermal shutdown, current limiting, and safe-area control have been designed into these units and since these regulators require only a small output capacitor for satisfactory performance, ease of application is assured. Although designed as fixed-voltage regulators, the output voltage can be increased through the use of a simple voltage divider. The low quiescent drain current of the device ensures good regulation when this method is used. Product is available in hermetically sealed TO-257 (both case grounded ‘G’ and isolated ‘IG’), TO-3, TO-39 and leadless chip carrier (LCC) packages. **Microchip Ordering Part** [**Standard Microcircuit Drawing (SMD)**](https://ww1.microchip.com/downloads/en/DeviceDoc/00003952.pdf) SG7815AG-DESC Cross Reference 5962-8855301TA SG7815AG-DESC Cross Reference 5962-8855301TX SG7815AIG-DESC Cross Reference 5962-8855301UA SG7815AIG-DESC Cross Reference 5962-8855301UX SG7815AK-DESC Cross Reference 5962-8855301YA SG7815AK-DESC Cross Reference 5962-8855301YX SG7815AL-DESC Cross Reference 5962-88553012A SG7815AL-DESC Cross Reference 5962-88553012X SG7815AT-DESC Cross Reference 5962-8855301XA SG7815AT-DESC Cross Reference 5962-8855301XX

The SG78xxA/SG78xx series of positive regulators offer self-contained, fixed-voltage capability with up to 1.5 A of load current and input voltage up to 50 V (SG78xxA series only). These units feature a unique on-chip trimming system to set the output voltages to within ±1.5% of nominal on the SG78xxA series with ±2.0% on the SG78xx series. The SG78xxA versions also offer much improved line and load regulation characteristics. Utilizing an improved bandgap reference design, problems such as drift in output voltage and large changes in the line and load regulation, that are normally associated with the Zener diode references have been eliminated. All protective features of thermal shutdown, current limiting, and safe-area control have been designed into these units and since these regulators require only a small output capacitor for satisfactory performance, ease of application is assured. Although designed as fixed-voltage regulators, the output voltage can be increased through the use of a simple voltage divider. The low quiescent drain current of the device ensures good regulation when this method is used. Product is available in hermetically sealed TO-257 (both case grounded ‘G’ and isolated ‘IG’), TO-3, TO-39 and leadless chip carrier (LCC) packages. **Microchip Ordering Part** [**Standard Microcircuit Drawing (SMD)**](https://ww1.microchip.com/downloads/en/DeviceDoc/00003952.pdf) SG7818AK-DESC Cross Reference 5962-8991501YA SG7818AK-DESC Cross Reference 5962-8991501YX

The SG78xxA/SG78xx series of positive regulators offer self-contained, fixed-voltage capability with up to 1.5 A of load current and input voltage up to 50 V (SG78xxA series only). These units feature a unique on-chip trimming system to set the output voltages to within ±1.5% of nominal on the SG78xxA series with ±2.0% on the SG78xx series. The SG78xxA versions also offer much improved line and load regulation characteristics. Utilizing an improved bandgap reference design, problems such as drift in output voltage and large changes in the line and load regulation, that are normally associated with the Zener diode references have been eliminated. All protective features of thermal shutdown, current limiting, and safe-area control have been designed into these units and since these regulators require only a small output capacitor for satisfactory performance, ease of application is assured. Although designed as fixed-voltage regulators, the output voltage can be increased through the use of a simple voltage divider. The low quiescent drain current of the device ensures good regulation when this method is used. Product is available in hermetically sealed TO-257 (both case grounded ‘G’ and isolated ‘IG’), TO-3, TO-39 and leadless chip carrier (LCC) packages.