TM EV1529DR-00A Fixed Frequency Step-Up Converter LCD Backlight Plus Flash Evaluation Board The Future of Analog IC Technology TM GENERAL DESCRIPTION FEATURES The EV1529DR-00A evaluation board is designed to drive 2 strings of up to 4 backlight LEDs to 30mA and a 4-LED flash string to 150mA from a single Lithium-Ion battery. The board is set up to obtain 20mA backlight current, 40mA preview current and 100mA flash current. All the LED currents can be adjusted by resistors RS1, RS2, and RS3 on the evaluation board. • • • The MP1529 switches at 1.2MHz and allows the use of tiny, low cost capacitors and small inductors. High frequency PWM dimming is made possible through EN1. The MP1529 includes built-in open-LED over-voltage protection, cycle-by-cycle current limit, overtemperature shutdown, input under-voltage control and integrated soft-start. ELECTRICAL SPECIFICATIONS Parameter Supply Voltage LED Current (Backlight) LED Current (Preview) LED Current (Flash) Symbol Value Units VIN 2.7-4.2 20 40 100 V mA mA mA ILED_BL ILED_PV ILED_FL • • • • • High Efficiency 2.7V to 4.2V Input Voltage Range Tiny Capacitors and Inductors Due to 1.2MHz Fixed Frequency Operation LCD Backlight to 30mA, Flash to 150mA Independent Backlight, Preview and Flash Current Adjustment High Frequency PWM Dimming Surface-Mount Components Fully Assembled and Tested APPLICATIONS • • • • PDAs Cellular Phones Digital Still Cameras Digital Video Cameras “MPS” and “The Future of Analog IC Technology” are Trademarks of Monolithic Power Systems, Inc. EV1529DR-00A EVALUATION BOARD (L x W x H) 2.2” x 1.8” x 0.4” (5.5cm x 4.8cm x 1.0cm) EV1529DR-00A Rev. 1.0 11/2/2005 Board Number MPS IC Number EV1529DR-00A MP1529DR www.MonolithicPower.com MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited. © 2005 MPS. All Rights Reserved. 1 TM EV1529DR-00A – FIXED FREQUENCY CONVERTER LCD BACKLIGHT EV BOARD EVALUATION BOARD SCHEMATIC VIN D1 1N5819HW-7 GND U1 MP1529 1 VIN 2 3 4 EN1 R1 NS GND R2 NS R3 NS C3 NS VOUT 16 15 14 13 VCC PGND SW PGND EN1 OUT EN2 ISET3 COMP ISET2 SS ISET1 12 11 6 7 LED5 LED9 LED2 LED6 LED10 LED3 LED7 LED11 LED4 LED8 LED12 9 GND LED3 GND LED2 LED1 5 LED1 10 8 C4 10nF VIN EN2 GND EV1529_S01 EV1529DR-00A BILL OF MATERIALS Qty Ref Value 1 C1 10µF 1 C2 2.2µF 1 C3 1 C4 10nF 1 C5 1µF 1 1 D1 L1 LED1, LED2, LED3, LED4, LED5, LED6, LED7, LED8, LED9, LED10, LED11, LED12 R1, R2, R3 RS1 RS2 RS3 U1 12 3 1 1 1 1 EV1529DR-00A Rev. 1.0 11/2/2005 10µH Description Ceramic Capacitor, 10V, X5R Ceramic Capacitor, 25V, X7R Do Not Stuff Ceramic Capacitor, 50V, X7R Ceramic Capacitor, 25V, X5R Diode Schottky, 40V, 1A Inductor, 1.8A Package Manufacturer Manufacturer P/N 1210 TDK C3225X5R1A106K 1210 TDK C3225X7R1E225M 0805 TDK C2012X7R1H103K 0805 TDK C2012X5R1E105K SOD123 SMD Diodes Inc. Coiltronics 1N5819HW-7 SD25-100 0603 0603 0603 QFN16 Any Any Any MPS MP1529DR Not Stuffed Not Stuffed 57.6kΩ Resistor, 1% 33.2kΩ Resistor, 1% 12.1kΩ Resistor, 1% Step-Up Converter www.MonolithicPower.com MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited. © 2005 MPS. All Rights Reserved. 2 TM EV1529DR-00A – FIXED FREQUENCY CONVERTER LCD BACKLIGHT EV BOARD PRINTED CIRCUIT BOARD LAYOUT Figure 1—Top Silk Layer Figure 2—Top Layer Figure 3—Bottom Layer EV1529DR-00A Rev. 1.0 11/2/2005 www.MonolithicPower.com MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited. © 2005 MPS. All Rights Reserved. 3 TM EV1529DR-00A – FIXED FREQUENCY CONVERTER LCD BACKLIGHT EV BOARD QUICK START GUIDE The LED currents at backlight mode, backlight plus review mode and flash mode are set to 20mA, 40mA, and 100mA, respectively on this board. The board layout accommodates mostly common used inductors and output capacitors. 1. Preset Power Supply to 2.7V ≤ VIN ≤ 4.2V. 2. Turn Power Supply off. 3. Connect Power Supply terminals to: a. Positive (+): VIN b. Negative (–): GND 4. Solder the first backlight LED string to LED1 - LED4. Solder the second backlight LED string to LED5 – LED8. Solder the flash LED string to LED9 – LED12. Set EN1 and EN2 based on the Enable Operation Table below. Connect EN1, EN2 to VIN to set them “H” and to GND to set them “L”. Mode EN1 EN2 Off Backlight Backlight plus Preview Flash L H (PWM) H (PWM) L L L H H Strings 1+2: LCD Backlight LEDs Off On (PWM) On (PWM) Off String 3: Flash LEDs Off Off Preview current Flash current 5. Turn Power Supply on after making connections. The LED currents can be adjusted by changing the values of resistors RS1, RS2, and RS3. VSET = 1.216V. RS1 = 950 × VSET ILED _ BL RS2 = 1100 × VSET ILED _ PV RS3 = 1000 × VSET ILED _ FL For examples, If ILED_BL = 10mA, then RS1 = 950 × 1.216 = 115.52kΩ (Use a 115kΩ 1% resistor) 10 If ILED_PL = 20mA, then RS2 = 1100 × 1.216 = 66.88kΩ (Use a 66.5kΩ 1% resistor) 20 If ILED_FL = 150mA, then RS3 = 1000 × 1.216 = 8.11kΩ (Use a 8.06kΩ 1% resistor) 150 NOTICE: The information in this document is subject to change without notice. Please contact MPS for current specifications. Users should warrant and guarantee that third party Intellectual Property rights are not infringed upon when integrating MPS products into any application. MPS will not assume any legal responsibility for any said applications. EV1529DR-00A Rev. 1.0 11/2/2005 www.MonolithicPower.com MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited. © 2005 MPS. All Rights Reserved. 4