Rev. 3/23/01

SP6650 Evaluation Board Manual

© Copyright 2001 Sipex Corporation

2

RB

100k

SP6650

10

9

8

7

6

1

2

3

4

5

10.0

1.0

µF

L1 22

µH

47

µF

RF

OPEN

R1

100k

BLON

SHDN

LX

PGND

GND

FB

47

µF

3

2

1

3

2

1

®

®

D1*

MBR0540TI

Figure 1. SP6650 Evaluation Board Schematic

The SP6650 Evaluation Board provides conve-

nient test points to connect the input to Power

Supply or Li-Ion Battery. The Input and Output

connections are made with raised female pin

receptacles which can accommodate easy-hook

connection leads for power and meter connec-

tions, as well as scope probe hooks and grounds

for waveform measurements.

USING THE EVALUATION BOARD

1) Powering Up the SP6650 Circuit

The SP6650 Evaluation Board can be powered

from a single Li-Ion battery or a +2.7 to +6.5V

power supply. Connect with short leads directly

will remain in “shutdown” until pin 2 of the

Jumper J2 is applied to the GND.

2) I LIM Programming

peak Inductor current limit (pins 2,3 of the

Jumper J2).

Connect pin 4 of the SP6650 to GND for 0.35

A peak Inductor current limit (pins 1,2 of the

Jumper J2).

3) V

To control the output voltage externally con-

nect the appropriate resistors (Table 1)

From pin 6 SP6650 FB to V

GND.

Tie Pin 6 FB to the 100k resistor or to the

GND and controller will use the internal

network for a preset output Voltage of 3.3V.

For V

1, use equation:

RF =

1.25

(For V