CPC9909DB - IXYS Integrated Circuits Division

CPC9909EB-R01 www.clare.com 1

CPC9909EB

Hi-Brightness, Off-Line LED Driver

Evaluation Board User’s Guide

Specifications Introduction

Clare's CPC9909 Evaluation Board contains all the

necessary circuitry to demonstrate all the features of

CPC9909 High Brightness (HB), Off-Line LED driver.

The CPC9909 IC architecture includes pulse

frequency modulation (PFM) with a constant

peak-current control scheme. This regulation scheme

is inherently stable, allowing the driver to operate

above 50% duty cycle without open-loop instability or

sub-harmonic oscillations. This greatly increases the

number of LEDs in series that can be driven by the

CPC9909 and by this Evaluation Board.

Linear LED dimming can be achieved either by

adjusting the on-board potentiometer, RA1, or by

adjusting the voltage at the LD pin. In addition, PWM

dimming can be achieved with a user-applied

TTL-level, low frequency, pulse-width-modulated

square wave signal between JP1-1 (GND) and

JP1-2 (connected to the PWMD pin of the CPC9909).

Figure 1. CPC9909 Evaluation Board, Top View

Parameter Min Typ Max Unit

Input Voltage

AC - - 265 Vrms

DC 15 - 375 VDC

Load Current - - 350 mA

Efficiency - 90 - %

WARNING!

This demonstration board must

be powered through an isolation

transformer before connecting

any external AC instrumentation

VIN

90VAC to 265VAC

External Power

LED - 350mA max LED +

VDD Monitor

RA1 - External

Current Sense

Threshold Adj.

LD Monitor

JP1 - External PWMD

Control Input

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CPC9909 Evaluation Board User’s Guide

1. Setup. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

1.1 CPC9909 Evaluation Board Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

1.2 Demo Board Connection Descriptions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

1.3 CPC9909 Evaluation Board Bill of Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

2. Performance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

2.1 Typical Output Waveforms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

3. PC Board Layout Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

4. PC Board Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

CPC9909 Evaluation Board User’s Guide

R01 www.clare.com 3

1. Setup

1.1 CPC9909 Evaluation Board Schematic

1.2 Demo Board Connection Descriptions

* Note that the demo board and the connected LED's are not isolated from line voltage, therefore an isolation

transformer should be used to protect the user and all measuring instruments such as oscilloscope and multi-meters.

Name Description

LED+ LED+ is connected to the anode end of the LED string

LED- LED- is connected to the cathode end of the LED string

J2 *

VIN AC input: 265Vrms (max) - or - DC input: 15VDC to 375VDC (not DC polarity sensitive)

VDD Monitor This pin is connected to the VDD pin of the CPC9909. The typical voltage regulator output is set at 7.8V, and can be used

to provide bias voltage to external circuits.

LD Monitor

The LD monitor pin is connected to the wiper of the potentiometer, RA1. The CPC9909 has a preset voltage level VCS(high)

which is typically set at 250mV. The LED drive current can be reduced in a linear fashion by adjusting RA1, thus pulling the

LD pin down to below 250mV.

JP1

External PWMD Control Input:

•Jumper pins 1&2 to disable the CPC9909 and place it into a low-current, standby state.

•Jumper pins 2&3 to enable the CPC9909; dimming is accomplished with the potentiometer, RA1.

•No Jumper. Apply a TTL-level PWM signal in the 500Hz range to pin 2 to enable dimming under PWM control. The PWM

signal’s duty cycle determines LED brightness.

GND This pin is connected to the ground of buck LED driver.

265VAC (max)

EXT. POWER

VIN

FUSE F2

NTC1

BR1

DF04S

LED CONNECTION

LED+

LED-

4.7mH

BYV26B

IXTA8N50N

0.56Ω

0.1μF

400V

22μF

400V

402kΩ

CPC9909

8-PIN SOIC

VIN

PGND

GATE

VDD

PWMD

JP1

132

0.1μF

25V

51kΩ

0Ω

RA1

5kΩ

2.2μF

16V

VDD MONITOR

LD MONITOR

DUT1

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CPC9909 Evaluation Board User’s Guide

1.3 CPC9909 Evaluation Board Bill of Materials

Designator Qty. Description Part Number

BR1 1 IC, Rectifier Bridge, 400V, 1.5A DF04S

C1 1 Capacitor, Polarized, 0.5 WD, 22μF, 4 0 0 VEXXG401ELL22CMK20S

C2 1 Capacitor, Axial, 0.6 x 0.35, 0.1μF, 4 0 0 VB32652A4104J

C3 1 Capacitor, 2.2μF, 1 6 VGRM21BR61C225KA88L

C4 1 Capacitor, 0.1μF, 2 5 VGRM216F51E104ZA01D

D1 1 BYV26B, 1A, 400VBYV26B-TR

DUT1 1 Clare CPC9909 CPC9909

F1 1 Fuse Holder, Thru-Hole, PC Mount 5600000100

F2 1 Fuse, 2A, 250V37312000410

J1 1 2-Position Terminal Block 39544-3002

J2 1 2-Position Terminal Block 39544-3002

JP1 1 3-Position Jumper 800-10-064-10-001000 w/shunt

929950-00

JP2 1 Wire Jumper, 0.3 (Included)

L1 1 Inductor, Axial, 4.7mH, 0.4A 5900-472-RC

NTC1 1 Thermistor, Inrush Current Limiter CL-130

Q1 1 IXYS FET, With Aavid Thermalloy Heat Sink IXTA8N50P w/heatsink 573100D00000

R1 1 Resistor, Surface Mount, 402k RC0805FR-07402KL

R2 1 Resistor, Surface Mount, 51k RC0805FR-0751K1L

R3 1 Resistor, Surface Mount, 0 Ohms RC0805JR-070RL

R4 1 Resistor, Surface Mount, 0.56 RL1220S-R56-F

RA1 1 Variable Resistor, 5k 3314G-1-502E

TP2 1 Test Point 10-138-2-01

TP3 1 Test Point 10-138-2-01

TP4 1 Test Point 10-138-2-01

CPC9909 Evaluation Board User’s Guide

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2. Performance

2.1 Typical Output Waveforms

3. PC Board Layout Considerations

Proper PCB layout should include a short, thick trace

from pin 4 of the CPC9909 internal gate driver to the

gate of the external power MOSFET.

In addition, the current sense resistor, connected to

pin 2, and the one-shot programming resistor,

connected to pin 8, should be placed as close as

possible to pin 2 and pin 8 respectively to minimize

any noise coupling to the CS and RT pins.

Please note that in some cases, during turn-off

transitions of the external power MOSFET, high

current spikes from the external inductor can develop.

In this case, the design may require placing a high

voltage capacitor, 100nF or higher, between the LED+

and LED- terminals to filter these current spikes.

Input Voltage = 110VAC

CH3: LED Current, 10mVΩ = 100mA/div

CH4: MOSFET drain voltage, 50V/div

Frequency = 84kHz, positive duty cycle = 55.4%

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CPC9909 Evaluation Board User’s Guide

4. PC Board Layout

For additional information please visit our website at: www.clare.com

Clare, Inc. makes no representations or warranties with respect to the accuracy or completeness of the contents of this publication and reserves the right to make changes to specifications and

product descriptions at any time without notice. Neither circuit patent licenses nor indemnity are expressed or implied. Except as set forth in Clare’s Standard Terms and Conditions of Sale,

Clare, Inc. assumes no liability whatsoever, and disclaims any express or implied warranty, relating to its products including, but not limited to, the implied warranty of merchantability, fitness for

a particular purpose, or infringement of any intellectual property right.

The products described in this document are not designed, intended, authorized or warranted for use as components in systems intended for surgical implant into the body, or in other

applications intended to support or sustain life, or where malfunction of Clare’s product may result in direct physical harm, injury, or death to a person or severe property or environmental

damage. Clare, Inc. reserves the right to discontinue or make changes to its products at any time without notice.

Specification: UG-CPC9909EB-R01

6/17/2010