SC2453 Datasheet | SEMTECH

Description SC2453 is a high performance multi-output converter controller that can be configured for a variety of applications. The SC2453 utilizes synchronous rectified buck topologies where efficiency is most important. It also provides dedicated programmable positive and negative linear regulators using external transistors in conjunction with coupled windings to generate positive and negative voltages. Power up sequencing prevents converter latchups. The two buck converters are out of phase, reducing input ripple, allowing for fewer input capacitors. All converters are synchronized to prevent beat frequencies. High frequency operation will reduce ripple and minimize noise. It also reduces the size of output inductors and capacitors. Other Features include soft start, power-good signaling, bootstrapping for high side MOSFETs, and frequency synchronization. PRELIMINARY Features ‹ ‹ ‹ ‹ ‹ ‹ ‹ ‹ ‹ ‹ ‹ Two synchronized converters for low noise Power up sequencing to prevent latch-ups Out of phase operation for low input ripple Over current protection Wide input range, 4.5 to 30V Programmable frequency up to 700KHz Two synchronous bucks for high efficiency at high current One dedicated programmable positive linear regulator and one dedicated programmable negative linear regulator - 40 to 105 degree C operating temperature Output voltage as low as 0.5V Small package TSSOP-28 Applications ‹ DSL applications with multiple input voltage requirements ‹ Mixed-Signal applications requiring positive and negative voltages ‹ Cable modem power management ‹ Base station power management Typical Application Circuit +8-30V Q1 C29 C30 C29 R28 C32 16 C29 6 9 R31 7 8 AVCC SS OSC SYNC/SHDN POK 22 PVCC 28 BDI 27 VIN BST2 GD2H PH2 GD2L FB2 Q2 R31 4 BD4 SC2453 EO2 BST1 5 R31 C32 11 BD3 C31 10 C32 R32 C32 FB3 AGND PGND 15 21 ILIM2 14 ILIM1 1 R28 R31 FB4 GD1H PH1 GD1L FB1 EO1 17 18 19 20 13 12 26 25 24 23 2 3 D10 D11 D11 C31 Q11 L8 C30 +3.3V C33 R30 +3.3V C32 C29 Q11 R3...