-5V/-12V/-15V or Adjustable,

______________________________________________________________________________________

11

Table 1. Component Suppliers

PRODUCTION METHOD

INDUCTORS

CAPACITORS

DIODES

Surface Mount

Matsuo

267 series

Sprague

595D/293D series

AVX

TPS series

Nihon

EC10QS02L (Schottky)

EC11FS1 (high-speed silicon)

Miniature Through-Hole

Sumida

RCH895 series

Sanyo

OS-CON series (very low ESR)

Low-Cost Through-Hole

Renco

RL1284 series

Nichicon

PL series

Motorola

1N5817, 1N5818, (Schottky)

MUR105 (high-speed silicon)

Sumida

CD75/105 series

Coiltronics

CTX series

Coilcraft

DT/D03316 series

Reference Capacitor

Bypass REF with a 0.1µF capacitor (C3). The REF out-

put can source up to 100µA for external loads.

Layout Considerations

Proper PC board layout is essential to reduce noise

generated by high current levels and fast switching

waveforms. Minimize ground noise by connecting

GND, the input bypass capacitor ground lead, and the

output filter capacitor ground lead to a single point (star

ground configuration). Also minimize lead lengths to

reduce stray capacitance, trace resistance, and radiat-

ed noise. In particular, keep the traces connected to

FB and LX short. C2 must be placed as close as pos-

sible to the V+ and GND pins. If an external resistor

divider is used (Figure 3), the trace from FB to the resis-

tors must be extremely short.

SUPPLIER

PHONE

FAX

AVX

USA:

(803) 448-9411

(803) 448-1943

Coilcraft

USA:

(708) 639-6400

(708) 639-1469

Coiltronics

USA:

(407) 241-7876

(407) 241-9339

Matsuo

USA:

(714) 969-2491

Japan: 81-6-337-6450

(714) 960-6492

81-6-337-6456

Motorola

USA:

(800) 521-6274

(602) 952-4190

Nichicon

USA:

(708) 843-7500

Japan: 81-7-5231-8461

(708) 843-2798

81-7-5256-4158

Renco

USA:

(516) 586-5566

(516) 586-5562

Sanyo OS-CON

USA:

(619) 661-6835

Japan: 81-7-2070-1005

(619) 661-1055

81-7-2070-1174

Sprague Electric Co.

USA:

(603) 224-1961

(603) 224-1430

Nihon

USA:

(805) 867-2555

Japan: 81-3-3494-7411

(805) 867-2556

81-3-3494-7414

Sumida

USA:

(708) 956-0666

Japan: 81-3-3607-5111

(708) 956-0702

81-3-3607-5144