Datasheet LT8645S, LT8646S (Analog Devices) - 16
| Manufacturer | Analog Devices |
| Description | 65V, 8A Synchronous Step-Down Silent Switcher 2 with 2.5μA Quiescent Current |
| Pages / Page | 30 / 16 — Low EMI PCB Layout. a) LT8645S. b) LT8646S. Figure 1. Recommended PCB … |
| File Format / Size | PDF / 457 Kb |
| Document Language | English |
Low EMI PCB Layout. a) LT8645S. b) LT8646S. Figure 1. Recommended PCB Layouts for the LT8645S and LT8646S
Text Version of Document
LT8645S/LT8646S APPLICATIONS INFORMATION
Low EMI PCB Layout
Two small 0.47µF capacitors can be placed as close as The LT8645S/LT8646S is specifically designed to minimize possible to the LT8645S/LT8646S: One capacitor on each EMI/EMC emissions and also to maximize efficiency when side of the device (COPT1, COPT2). A third capacitor with a switching at high frequencies. For optimal performance larger value, 4.7µF or higher, should be placed near COPT1 the LT8645S/LT8646S should use multiple V or COPT2. IN bypass capacitors. See Figure 1 for a recommended PCB layouts. CC R2 R2 C1 R CSS C1 C CF CSS V R1 R1 V V V V V RT RT V V C C C C C OPT1 OPT2 IN3 COPT1 OPT2 IN3 COUT COUT L L 8645S F01a 8645S F01b GROUND VIA VIN VIA VOUT VIA V OTHER SIGNAL VIAS GROUND VIA VIN VIA VOUT VIA V OTHER SIGNAL VIAS
a) LT8645S b) LT8646S Figure 1. Recommended PCB Layouts for the LT8645S and LT8646S
8645Sfa 16 For more information www.linear.com/LT8645S
Low EMI PCB Layout
Two small 0.47µF capacitors can be placed as close as The LT8645S/LT8646S is specifically designed to minimize possible to the LT8645S/LT8646S: One capacitor on each EMI/EMC emissions and also to maximize efficiency when side of the device (COPT1, COPT2). A third capacitor with a switching at high frequencies. For optimal performance larger value, 4.7µF or higher, should be placed near COPT1 the LT8645S/LT8646S should use multiple V or COPT2. IN bypass capacitors. See Figure 1 for a recommended PCB layouts. CC R2 R2 C1 R CSS C1 C CF CSS V R1 R1 V V V V V RT RT V V C C C C C OPT1 OPT2 IN3 COPT1 OPT2 IN3 COUT COUT L L 8645S F01a 8645S F01b GROUND VIA VIN VIA VOUT VIA V OTHER SIGNAL VIAS GROUND VIA VIN VIA VOUT VIA V OTHER SIGNAL VIAS
a) LT8645S b) LT8646S Figure 1. Recommended PCB Layouts for the LT8645S and LT8646S
8645Sfa 16 For more information www.linear.com/LT8645S
