AMC7140 700mA HIGH VOLTAGE ADJUSTABLE CURRENT REGULATOR WITH ENABLE CONTROL www.addmtek.com DESCRIPTION FEATURES The AMC7140 is a high voltage, low drop-out current regulator for maximum output current up to 700mA. The output current was decided by external resistor. The output sink current could be disabled via OE pin Build-in thermal protection to prevent the chip over heat damage. 0.5V Output Drop-out Voltage at 700mA. 700mA Maximum Output Current. Output Current Controlled by External Resistor. 3us Fast Response Output Stage Enable Control. Output Driving Voltage Up To 75V. Supply Voltage Range 5V~50V TO-252-5L package TYPICAL APPLICATION CIRCUIT APPLICATIONS 5V~50V High Power LED Driver RGB Full Color Power LED driver LCD Monitor/TV LED backlight Driver LED Table Lamp CBP PACKAGE PIN OUT VDD Enable OE AMC7140 ISET RSET OUT GND 5 OUT 4 OE 3 GND 2 ISET 1 VDD TO-252-5L (Top View) ORDER INFORMATION DL Note: TO-252 5 pin AMC7140DLFT (Lead Free) All surface-mount packages are available in Tape & Reel. Append the letter “T” to part number (i.e. AMC7140DLFT). The letter ”F” is marked for Lead Free process. Copyright © 2007 ADDtek Corp. 1 DD032_B -- APRIL 2007 AMC7140 ABSOLUTE MAXIMUM RATINGS (Note) 50V 75V 150°C -65°C to 150°C 260°C Input Voltage, VDD Output Voltage, VOUT Maximum Operating Junction Temperature, TJ Storage Temperature Range Lead Temperature (soldering, 10 seconds) Note: Exceeding these ratings could cause damage to the device. All voltages are with respect to Ground. Currents are positive into, negative out of the specified terminal. PIN DESCRIPTION Pin Name Pin Function OUT Output pin. Sink current is decided by the current on RSET connected to ISET. IOUT = 500 × ISET. OE Output stage enable control pin. High enable the OUT pin. ISET Output current set input. Connect a resistor from ISET to GND to set the LED bias current. ISET = 1.2V/RSET. VDD Power supply. GND Ground THERMAL DATA Thermal Resistance from Junction to Ambient, θ JA 80 OC /W Junction Temperature Calculation: TJ = TA + (PD × θ JA). The θJA numbers are guidelines for the thermal performance of the device/pc-board system. Connect the ground pin to ground using a large pad or ground plane for better heat dissipation. All of the above assume no ambient airflow. Maximum Power Calculation: PD(MAX)= TJ(MAX) – TA(MAX) θJA TJ(OC): Maximum recommended junction temperature TA(OC): Ambient temperature of the application θJA(OC /W): Junction-to-Ambient temperature thermal resistance of the package, and other heat dissipating materials. The maximum power dissipation for a single-output regulator is: PD(MAX) = [(VIN(MAX) - VOUT(NOM))] × IOUT(NOM) + VIN(MAX) × IQ Where: Then VOUT(NOM) = the nominal output voltage IOUT(NOM) = the nominal output current, and IQ = the quiescent current the regulator consumes at IOUT(MAX) VIN(MAX) = the maximum input voltage θJA = (+150 OC – TA)/PD Copyright © 2007 ADDtek Corp. 2 DD032_B -- APRIL 2007 AMC7140 RECOMMENDED OPERATING CONDITIONS Symbol Min Typ Supply Voltage VDD 5 Output Sink Current IOUT Operating free-air temperature range Ta -40 Parameter Max 50 700 +85 Unit V mA ℃ DC ELECTRICAL CHARACTERISTICS VDD=24V, Ta=25°C, No Load, (Unless otherwise noted) Parameter Output Current Output Current Deviation Condition Min Typ VOUT=0.5V, RSET=4KΩ 150 VOUT=0.5V, RSET=1.2KΩ 500 Max mA VOUT=0.5V, RSET=4KΩ ±5 VOUT=0.5V, RSET=1.2KΩ ±5 SET Current Range 200 Unit 1400 % µA Maximum Output Current ISET=1400uA 700 mA Output Drop-out Voltage* ISET=1000uA, Note 1 0.35 V Thermal Shut-down Junction Temperature Hysteresis 20℃ 160 ℃ “Low” Input Voltage 0 0.8 V “High” Input Voltage 2 12 V “Low” Input Current -20 +20 µA “High” Input Current -5.0 +5.0 µA Output Enable Delay Time OE from Low to High, VOUT=0.5V, IOUT=350mA, 50% 3 µS Output Disable Delay Time OE from High to Low, VOUT =0.5V, IOUT=350mA, 50% 3 µS Supply Current Consumption 5 mA Note1: Output dropout voltage: 90% x IOUT @ VOUT=500mV Copyright © 2007 ADDtek Corp. 3 DD032_B -- APRIL 2007 AMC7140 CHARACTERIZATION CURVES ISET Voltage vs. Junction Temperature Supply Current vs. Supply Voltage 1.50 IOUT =700mA 4 3 ISET Voltage (V) Supply Current (mA) 5 IOUT =500mA 2 1 0 20 40 1.30 1.20 1.10 V DROP =0.5V TA =25°C 0 1.40 V DD=24V 1.00 -50 60 50 100 150 Output Current vs. Dropout Voltage Output Current vs. Supply Voltage 500.0 600 500 IOUT =500mA Output Current (mA) Output Current (mA) 0 Junction Temperature (°C) Supply Voltage (V) 400 300 200 IOUT =150mA 100 V DROP =0.5V TA =25°C 0 0 20 40 IOUT =340mA 300.0 200.0 IOUT =150mA 100.0 V DD=24V TA=25°C 0.0 0.00 60 1.00 2.00 3.00 Dropout Voltage (V) Supply Voltage (V) Copyright © 2007 ADDtek Corp. 400.0 4 DD032_B -- APRIL 2007 AMC7140 APPLICATION INFORMATION AMC7140 is a high voltage, low dropout current regulator for maximum output current up to 700mA with OE pin. The current could be linearly adjusted through variable resister connected to ISET pin, or by PWM control via OE pin. Although the absolute maximum rating of OUT pin 60V, the dropout voltage between OUT pin and GND pin should not be too large when current is sinking because of the heat dissipation capability of the package. Here are some of the typical application examples: DC Voltage Input: Any DC voltage level between 5V to 50V could be adopted as power source VDD for typical application of AMC7140 as long as VDD is larger than the total forward voltage drop of the LED string (at expecting current) by 0.35V. If 50V ~ 60V voltage level is adopted as power source to positive end of the LED string, one Zener shunt regulator could be used to provide appropriate voltage to VDD pin. ＜50VDC ＞50VDC RZ CIN VDD OE Enable ISET CIN OUT AMC7140 OE Enable ISET GND DZ RSET1 RSET2 OUT VDD AMC7140 GND RSET1 RSET2 880Ω Copyright © 2007 ADDtek Corp. 5 880Ω DD032_B -- APRIL 2007 AMC7140 LED Backlight Solution: AMC7140 could coordinate with any type of DC-to-DC converter through feedback path to realized LED backlight module. The number of LEDs in the string is variable even with certain fixed power source since the output voltage of the DC-to-DC converter could be modulated according to feedback signal. 1 2V DC o r 2 4V DC DC / DC C o n v e rte r O u tp u t FB Db Rb OUT VDD OE E n a b le IS E T AM C7140 GND R SET1 R SET2 880Ω AC Voltage Input: AMC7140 could work with any kind of well-known or well-developed switch-mode power supply system. Simply cut off the internal feedback path of the power supply system and then feed the signal from AMC7140 back to the power supply system instead. 85VAC ~ 265 VAC VDD Power Supply FB Rb Db OUT VDD OE Enable ISET AMC7140 GND RSET1 RSET2 Copyright © 2007 ADDtek Corp. 880Ω 6 DD032_B -- APRIL 2007 AMC7140 THERMAL CONSIDERATION The Maximum Power Dissipation on Current Regulator: PD(MAX) = VOUT(MAX) × IOUT(NOM) + VIN(MAX) × IDD VOUT(MAX) = the maximum voltage on output pin; IOUT(NOM) = the nominal output current; IDD = the quiescent current the regulator consumes at IOUT(NOM); VIN(MAX) = the maximum input voltage. Thermal Consideration: The AMC7140 has internal power and thermal limiting circuitry designed to protect the device under overload conditions. However, maximum junction temperature ratings should not be exceeded under continuous normal load conditions. The thermal protection circuit of AMC7140 prevents the device from damage due to excessive power dissipation. When the device junction temperature rises to approximately 150°C, the regulator will be turned off. When power consumption is over about 1000mW (TO-252 package, at TA=70°C), additional heat sink is required to control the junction temperature below 125°C. The junction temperature is: TJ = PD (θJT +θCS +θSA ) + TA PD : Dissipated power. θJT: Thermal resistance from the junction to the mounting tab of the package. For TO-252 package, θJT = 7.0 oC /W. θCS: Thermal resistance through the interface between the IC and the surface on which it is mounted. (typically, θCS < 1.0°C /W) θSA: Thermal resistance from the mounting surface to ambient (thermal resistance of the heat sink). If PC Board copper is going to be used as a heat sink, below table can be used to determine the appropriate size of copper foil required. For multi-layered PCB, these layers can also be used as a heat sink. They can be connected with several through-hole vias. PCB θSA (°C /W) 2 PCB heat sink size (mm ) 59 500 45 1000 38 1500 33 2000 27 3000 24 4000 21 5000 Recommended figure of PCB area used as a heat sink. Heat-pad of TO-252 5 OUT 4 OE 3 GND 2 ISET 1 VDD Through hole vias Copyright © 2007 ADDtek Corp. 7 DD032_B -- APRIL 2007 AMC7140 PACKAGE TO-252-5L Symbol A A1 B C c1 D D1 E E e1 L1 L2 L3 V Copyright © 2007 ADDtek Corp. Dimensions in Millimeters MIN 2.200 0.000 0.400 0.430 0.430 6.350 5.200 5.400 MAX 2.400 0.127 0.600 0.580 0.580 6.650 5.400 5.700 Dimensions in Inches MIN 0.087 0.000 0.016 0.017 0.017 0.250 0.205 0.213 1.270 TYP 2.540 TYP 9.500 1.400 2.550 MAX 0.094 0.005 0.024 0.023 0.023 0.262 0.213 0.224 0.050 TYP 1.000 TYP 9.900 1.780 2.900 3.800 REF 0.374 0.055 0.100 0.390 0.070 0.114 0.150 REF 8 DD032_B -- APRIL 2007 AMC7140 IMPORTANT NOTICE ADDtek reserves the right to make changes to its products or to discontinue any integrated circuit product or service without notice, and advises its customers to obtain the latest version of relevant information to verify, before placing orders, that the information being relied on is current. A few applications using integrated circuit products may involve potential risks of death, personal injury, or severe property or environmental damage. ADDtek integrated circuit products are not designed, intended, authorized, or warranted to be suitable for use in life-support applications, devices or systems or other critical applications. Use of ADDtek products in such applications is understood to be fully at the risk of the customer. In order to minimize risks associated with the customer’s applications, the customer should provide adequate design and operating safeguards. ADDtek assumes to no liability to customer product design or application support. ADDtek warrants the performance of its products to the specifications applicable at the time of sale. ADDtek Corp. 9F, No. 20, Sec. 3, Bade Rd., Taipei, Taiwan, 105 TEL: 2-25700299 FAX: 2-25700196 Copyright © 2007 ADDtek Corp. 9 DD032_B -- APRIL 2007