The LTC1873EG is a dual switching regulator controller optimized for high efficiency with low input voltages. It includes two complete, on-chip, independent switching regulator controllers. Each is designed to drive a pair of external N-channel MOSFETs in a voltage mode feedback, synchronous buck configuration. The LTC1873EG includes digital output voltage adjustment on side 1 that conforms to the Intel Desktop VID specification. A constant-frequency, true PWM design minimizes external component size and cost and optimizes load transient performance. The synchronous buck architecture automatically shifts to discontinuous and then to Burst Mode™ operation as the output load decreases, ensuring maximum efficiency over a wide range of load currents.
The LTC1873EG features an onboard reference trimmed to 1% and delivers better than 1.5% regulation at the converter outputs over all combinations of line, load and temperature. Each channel can be enabled independently; with both channels disabled, the LTC1873EG shuts down and supply current drops below 100µA.
Feature
- Two Independent PWM Controllers in One Package
- Side 1 Output Is Compliant with Intel Desktop VRM 8.4 Specifications (Includes 5-Bit VID DAC)
- 1.3V to 3.5V Output Voltage with 50mV/100mV Steps
- Two Sides Run Out-of-Phase to Minimize CIN
- All N-Channel External MOSFET Architecture
- No External Current Sense Resistors Required
- Precison Internal 0.8V ±1% Reference
- 550kHz Switching Frequency Minimizes External Component Size
- Very Fast Transient Response
- Up to 25A Output Current per Channel
- Low Shutdown Current: < 100µA
- Small 28-Pin SSOP Package
Applications
- Microprocessor Core and I/O Supplies
- Multiple Logic Supply Generator
- High Efficiency Power Conversion
- Chipset Power Supply
(Picture: Pinout)
