SC5010 datasheet(22/36 Pages) SEMTECH

22 / 36 page

SC5010

Applications Information (continued)

Vin

(5-27V)

S C 5010

VCC

UVLO

SCP

FSET

AGND

9 10 11 12 13 14

IO8

IO7 16

IO6 17

IO5

IO4 19

IO3 20

IO2 21

THP

SDA

R15

SCL

PWMI

R10

Vcc (5V)

AGND

R11

SYNC

Vout

PAD

FLT

2.2μF

PGND

1μF

0.1



Figure 3 — SEPIC Configuration

High Output Voltage Configuration

If high output voltage application is required, an addi-

tional external cascode MOSFET can be added on each IO

pin to meet such requirement, please refer to figure 4 for

reference.

In this case, the upper limit on the output voltage is mainly

determined by the rating of the external MOSFET, heat

dissipation, etc.

PCB Layout Considerations

The placements of the power components outside the

SC5010 should follow the layout guidelines of a general

boost converter. The Detailed Application Circuit is used

as an example.

Capacitor (C2) should be placed as close as possible to

the VCC and AGND to achieve the best performance.

Capacitor (C1) is the input power filtering capacitor

for the boost, it needs to be tied to PGND.

The converter power train inductor (L1) is the boost

converter input inductor. Use wide and short traces

connecting these components.

The output rectifying diode (D1)

uses a Schottky

diode for fast reverse recovery. Transistor (Q1) is the

external switch. Resistor (R9) is the switch current

sensing resistor. To minimize switching noise for the

boost converter, the output capacitor (C6) should be

placed such that the loop formed by Q1, D1, C6 and

R9, is minimized. The output of the boost converter is

used to power up the LEDs. Use wide and short trace

connecting Pin DRVN and the gate of Q1. The GNDs

SC5010 датащи(PDF) 22 Page - Semtech Corporation

SC5010 датащи(HTML) 22 Page - Semtech Corporation

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36

датащи скачать

ссылки URL