Description of the board

UM0422

8/14

4.2

Setup

1.

operates between 4.5 V and 40 V. Ensure that the input voltage never exceeds the

STCS1 absolute maximum input voltage rating of 45 V.

2.

Connect the LEDs between the LED anode (J1 - A) and LED cathode (J1 - K)

connection points.

3.

4.

Enable jumper:

a)

En = GND shutdown

b)

En = 5 V ON mode

5.

Continuous current mode: PWM = 5 V

a)

Jumper between PWM and 5 V pins of J4 connector

b)

No jumper on J3 connector

6.

Dimming mode with the PWM signal of the oscillator implemented on evaluation board.

a)

No jumper on J4 connector

b)

Jumper on J3 connector

c)

R8: by changing the value of this resistor, the dimming frequency varies from

20 Hz up to 1.7 kHz

d)

R9: It is possible to change the duty cycle of the PWM signal from zero to 100%.

7.

Dimming mode with external PWM signal.

a)

No jumper on J3.

b)

External PWM signal between PWM-J4 and GND-J4 pins

J3/J4

PWM

Continuous current mode:

– J3: Floating

– J4: PWM and 5 V pins shorted.

PWM dimming mode with oscillator implemented on board.

In this configuration the PWM pin of STCS1 receives the PWM

signal generated by the oscillator on the board.

– J3: Shorted

– J4: Floating.

PWM dimming mode with external PWM signal:

– J3: Floating.

– J4: External PWM signal between PWM and GND pins.

J5

Slope

capacitor

Table 3.

Input/output connections (continued)

Reference

designator

Name

Description