700mA High Efficiency Step Down LED Driver

Size: px

Start display at page:

Download "700mA High Efficiency Step Down LED Driver"

Brittney Cooper
5 years ago
Views:

VLD 00mA High Efficiency FEATURES AND APPLICATIONS Power LED Driver Constant Current Output (% Output Current Accuracy) Wide Input Voltage Range: V to 0V (40V for 0.

1 VLD 00mA High Efficiency FEATURES AND APPLICATIONS Power LED Driver Constant Current Output (% Output Current Accuracy) Wide Input Voltage Range: V to 0V (40V for 0.5 sec) 6 Pin DIL Package LED Driver Current up to 00mA OutputPowerupto0W Driver LED Strings of up to V (V to V) RoHS High Efficiency (up to 5%) /Digital Dimming and Analog Voltage Dimming Open and Short LED Protection 40 C to 5 C Operation Temperature Range V and 4V Lighting Systems Household/Commercial lighting Suitable for high illumination LED Battery lighting systems GENERAL DESCRIPTION The VLDV0C00 is a high efficiency stepdown converter optimized to drive high current LEDs. The control algorithm allows highly efficient and accurate LED current regulation. The device operates from an input of Vdc to 0Vdc and provides an externally adjustable output current of up to 00mA and output power up to 0 Watts. Compact size of DIL6 allows designer to integrate this driver together with LED module. DIL 6 Package.40 (0.) 4.00 (0.55) Notes : All dimensions are typical in millimeters ( inches ).. Pin diameter: 0.5±0.05 ( 0.0±0.00 ). Pin pitch tolerance: ±0.5 ( ±0.04 ). Case Tolerance: ±0.5 ( ±0.0 ) 4.00 (0.55) DCDC LED DRIVER VLDV0C00 VITEC.05 (0.).6 (0.40).6 (0.40) DIA (0.0) VLDV0C00 Pin Connections Note, V Input DC Supply,, 5, 6 V adj V Output V Output V Input /on/off or not used LED Cathode Connection LED Anode Connection DC Supply. (0.0). (0.0)!.6 (0.40). (0.).54 (0.). (0.0) Bottom View (0.50) 0.50 (0.0) 0.50 (0.0) Recommended Foorprint Details.54 (0.) Top View /0.54 (0.) No connection is allowed between input and output Notes: Specifications can be changed without prior notice Products are not intended for and must not be used in life support systems, human implantation, nuclear facilities or systems or any other application where product failure or malfunction of the component could lead to loss of life or catastrophic property damage Hans Kudlich Gasse /, A0 Gänserndorf, Austria, Tel.: 4//44, Fax.: 4//6044, office@power.com

2 00mA High Efficiency ELECTRICAL SPECIFICATIONS Specifications typical at 5 C, nominal Input voltage, rated output current unless otherwise specified. Input Specifications Voltage Range Filter Vdc to 0Vdc (40V for 0.5 sec) Capacitor Output Specifications Voltage Range Vdc to V (Vin = 0Vdc) Current Range 00mA (Vin > V to V) Current Accuracy ±% (Iout = 00mA) Ripple and Noise (0 MHz BW) 50 mvpp, max. Short Circuit Protection Regulated at Rated Output Current Capacitive Load 4uF Dimming and On/Off Control Leave Open if Not Used Remote On/Off DC/DCOn Openor0.V<Vadj<.5V DC/DC off (Shutdown) Vadj < 0.5V Remote Pin Drive Current < ma (Vadj =.5V) Quiescent Input Current in Shutdown Mode 5uA (max, Vin = 0V) Dimming Recommended Maximum Operating Frequency Minimum Switch ON Time 00ns Minimum Switch OFF Time 00ns khz Environmental Specification Operating Temperature 40 C to 5 C Max. Case Temperature 0 C Storage Temperature 40 C to 5 C Thermal Impedance 50 C/W (Nature Convection) Cooling Freeair convection Temperature Coefficient ±0.05%/ C max. (Ta=40 C to 5 C) Analog Dimming Control Leave Open if Not Used Vadj Input Voltage Range 0.V to.5v Adjust Output Current 5% to 0% Control Voltage Range Limits On 0.V to 0.V Off 0.5V to 0.5V Analog Pin Drive Current < ma (Vadj =.5V) General Specification Efficiency 5% max. (Full Load) Switching Frequency 55 khz to 0 khz Humidity 5% rel H MTBF (MILHDBK F) > 4. Mhrs Physical Characteristics Dimension DIP.40 x 4.00 x.6 mm 0. x 0.55 x 0.40 inches Weight 6. g Case Material NonConductive Black Plastic (UL4V0 rated) Potting Material Epoxy (UL4V0 rated) Pin Material 0.5mm Brass Soldercoated Soldering Temperature 60 C (.5mmfrom case sec.) Notes. Reversed power source damages the circuit, No connection is allowed between input ground and output.. DO NOT operate the driver over 0W output.. Leave pin open if not in use, ground pin to shut down the converter. Connecting Vadj to Vin damages the circuit. 4. Maximum output open voltage is equal to input voltage. Hans Kudlich Gasse /, A0 Gänserndorf, Austria, Tel.: 4//44, Fax.: 4//6044, office@power.com

OUTPUT POWER VLD SERIES 00mA High Efficiency Typical Operating Conditions Derating Curve 50 Operating Frequency vs Input Voltage ( Electronic Load CV Mode Vf.5V ~ 4.5V ) 5 0% 00 5 LED 5% 50% 5% S.O.A. Frequency (KHz) 50 5 00 5 50 5 0 5 6LED 5LED 4LED LED LED 40 0 0 0 40 60 0 0 5 AMBIENT TEMPERATURE( C) 50 5 4564560 Vin (V) LED 0.

00 500.00 400.00 00.00 00.00 Vin=V Vout=.5V Vin=0V Vout=.5V Vin=0V Vout=4.5V 5.00% LED 0.00 0.00% 4564560 Vin (V) LED 0.00 0.05 0.5 0.5 0.5 0.45 0.55 0.65 0.5 0.5 0.5.05.5.5 (V) Recommended

3 OUTPUT POWER VLD SERIES 00mA High Efficiency Typical Operating Conditions Derating Curve 50 Operating Frequency vs Input Voltage ( Electronic Load CV Mode Vf.5V ~ 4.5V ) 5 0% 00 5 LED 5% 50% 5% S.O.A. Frequency (KHz) LED 5LED 4LED LED LED AMBIENT TEMPERATURE( C) Vin (V) LED 0.00% 5.00% ( Electronic Load CV Mode Vf.5V ~ 4.5V ) Vf=.0V Vf=4.5V Vf=.5V Vf=4.0V Vf=.5V Vf=.0V LED Output Current Vs Efficiency (%) 0.00% 5.00% 0.00% Vf=.5V 6LED 5LED 4LED LED ILED (ma) Vin=V Vout=.5V Vin=0V Vout=.5V Vin=0V Vout=4.5V 5.00% LED % Vin (V) LED (V) Recommended additional input filter VIN uf uh VIN EN550 CONDUCTIVE CLASS B FILTER SUGGESTION Analogue Dim Dim/ON/OFF 5 VLDV0C00 ( ) Vout Vin=0V Vout=V( Electronic Load CV Mode Vf V ) Vin=V Vout=V( Electronic Load CV Mode Vf V ) 6 Hans Kudlich Gasse /, A0 Gänserndorf, Austria, Tel.: 4//44, Fax.: 4//6044, office@power.com

4 00mA High Efficiency Typical Application Vin Vin Analogue ( Dim/ON/OFF) Vout 6 6 Vin 5 5 VLDV0C00 VLDV0C00 Vin Analogue ( Dim/ON/OFF) Vout AC IN 5Vac ~ Vac 0.uF optional 6 5 VLDV0C00 Vout AC IN 0uF ~ 0uF Analogue ( Dim/ON/OFF) Output Current Adjustment By External DC Control Voltage The nominal output current is then given by: 0.0 X Iout 0. DC VCTRL : 5V VLDV0C00 Vout 5V~Vin 4.K TL4 VLDV0C00 Vout R: 0K R:.5V VLDV0C00 Vout R = XVCTRL RR Resistor dimming By connecting a variable resistor between ADJ and, simple dimming can be achieved. Capacitor CADJ is optional for better AC mains interference and HF noise rejection. Recommend value of CADJ is 0.uF. CADJ RADJ VLDV0C00 Vout The current output can be determined using the equation: (0.0 / 0.) X RADJ Iout = (R ADJ 00K) Hans Kudlich Gasse /, A0 Gänserndorf, Austria, Tel.: 4//44, Fax.: 4//6044, office@power.com

5 00mA High Efficiency Typical Application Directly driving ADJ input A Pulse Width Modulated () signal with duty cycle D can be applied to the ADJ pin, asshown below.5v 0V Iout 0.D 0. Output Current Adjustment By Control [for 0<D <] VLDV0C00 Vout Driving the ADJ input via open collector transistor The diode and resistor suppress possible high amplitude negative spikes on the ADJ input resulting from the drains ource capacitance of the transistor. Negative spikes at the input to the device should be avoided as they may cause errors in output current, or erratic device operation. VLDV0C00 Vout Driving the ADJ input from a microcontroller Another possibility is to drive the device from the open drain output of a microcontroller. The diagram below shows one method of doing this: MCU VLDV0C00 Vout The diode and resistor suppress possible high amplitude negative spikes on the ADJ input resulting from the drains ource capacitance of the FET. Negative spikes at the input to the device should be avoided as they may cause errors in output current, or erratic device operation. Output Current Adjustment By Control (Dimming) To avoid visible flicker the signal must be greater than 0Hz. Vin Vin uf 5V 4 L05 uf 6V 40 N44 VR 0K 4 4 Vcc Reset Discharge 6 Threshold Out Trigger Crt_V NE SDK 4 N44 VLDV0C00 PIN (V ADJ) VLDV0C00 PIN Output Current Adjustment By Control (Flash) Vin Vin uf 5V 4 L05 uf 6V VR 0K K 4 Vcc Reset Discharge 6 Threshold Out 4 SDK N44 VLDV0C00 PIN (V ADJ) uf 6V Trigger NE 555 Ctr_V 5 4 VLDV0C00 PIN Hans Kudlich Gasse /, A0 Gänserndorf, Austria, Tel.: 4//44, Fax.: 4//6044, office@power.com

6 00mA High Efficiency Typical Application Output Current Adjustment By External DC Control Voltage N44 6.K :.5V VLDV0C00 Vout 5V ~ Vin TL4 4.K OUT : 0~.5V! In this application, the LED modules of each LED drivers should be independent from electrical connection to the others and input power this is to prevent the damaging to LED drivers also to avoid the unnecessaried interference among each LED module Vout N44 : 6.K.5V VLDV0C00 Vout N44 : 6.K.5V VLDV0C00 Vout N44 : 6.K.5V VLDV0C00 N44 : 6.K.5V VLDV0C00 Vout N44 : 6.K.5V VLDV0C00 Vout Vin Thermal feedback circuit R typ k BZX4C6V R 4.K Q 5 6 VLDV0C00 Vout R k Thermistor B 00 Thermally connected The selection of components for the thermal feedback circuit is not only dependent on the choice of R and R, but also on the amount of heat sink area required to extract heat from the LEDs. To maximize the light output at high ambient or operating temperature conditions, the LEDs must have a sufficient thermal extraction path, otherwise the thermal control circuit will effect current drive reduction in nonoptimal conditions. The thermal control threshold point is set by adjusting R. For this design, three values (k, k and k) were evaluated. These values were chosen to give break points at approximately 5 C, 40 C and 60 C. Note that the light output will not continually dim to zero the thermal controlis applying DC control to the ADJ pin and therefore has a dimming ratio from maximum Current of approximatley 5:. Once the reduced DC level goes below the shutdown threshold of around 00mV, the LED drive current will fall to zero and the LEDs will be extinguished. The slope of the current reduction is determinde by the beta value of the thermistor. The larger the beta value, the sharper will be the resultant current control response. The slope of the current reduction is also affected by Q's base emitter voltage (VBE) variation with temperture. Hans Kudlich Gasse /, A0 Gänserndorf, Austria, Tel.: 4//44, Fax.: 4//6044, office@power.com

Series AMLDLW-Z Up to 1000mA LED Driver

Series AMLDLW-Z Up to 1000mA LED Driver FEATURES: Wire Connections Operating Temperature range 40ºC to 85ºC Constant current output Open and Short LED Protection Wide (4:) input voltage range PWM/Digital and Analog Voltage dimming High efficiency