SC1565 Very Low Dropout 1.5 Amp Regulator With Enable POWER MANAGEMENT Description Features The SC1565 is a high performance positive voltage regulator designed for use in applications requiring very low dropout voltage at up to 1.5 Amps. Since it has superior dropout characteristics compared to regular LDOs, it can be used to supply 2.5V on motherboards or 2.8V on peripheral cards from the 3.3V supply thus allowing the elimination of costly heatsinks. Additionally, the 5-lead TO-220/TO-263 and SO-8 versions have an enable pin to further reduce power dissipation while shut down. The SC1565 provides excellent regulation over variations in line, load and temperature. 350mV dropout @ 1.5A Adjustable output from 1.2V to 4.8V(1) 2.5V and 1.8V options (adjustable externally using resistors)(1) Over current and over temperature protection Enable pin(1) 10µA quiescent current in shutdown(1) Low reverse leakage (output to input) Surface mount and through-hole packages Full industrial temperature range TO-220, TO-263, SOT-223 and SO-8 Packages Note: (1) SO-8, TO-220-5 and TO-263-5 packages only. The SC1565 is available in SO-8, 3-lead SOT-223, 3 and 5 lead TO-220 and 3 and 5 lead TO-263 packages. Three lead packages are available with 1.8V and 2.5V fixed output options only. The SO-8, TO-220-5 and TO-263-5 are available with 1.8V and 2.5V internally preset outputs that are also adjustable using external resistors. Applications Battery powered systems Motherboards Peripheral cards Network cards Set Top Boxes Medical Equipment Notebook Computers Typical Application Circuits U1 1 ENABLE 2 VIN 3 VO 4 R1 EN GND VIN GND VO GND ADJ GND 8 U1 7 1 ENABLE 6 2 VIN 5 3 VO SC1565IS-X.X 4 C1 C1 C2 EN GND VIN GND VO GND ADJ GND 8 7 6 5 SC1565IS-X.X C2 R2 VO = 1.200 (R1 + R2) R2 Volts VO U1 SC1565I5T-X.X 2 VIN ENABLE U1 SC1565IT-X.X 1 VIN VIN VO 1 3 VO VIN EN VO GND ADJ = 1.200 (R1 + R2) R2 4 5 Volts VO R1 3 C1 C2 GND C1 C2 R2 2 Notes: (1) Maximum VO setpoint for 1.8V parts = 5.4V. (2) This device is designed to operate with ceramic input and output capacitors. Revision: April 27, 2005 1 www.semtech.com SC1565 POWER MANAGEMENT Absolute Maximum Ratings Exceeding the specifications below may result in permanent damage to the device, or device malfunction. Operation outside of the parameters specified in the Electrical Characteristics section is not implied. Parameter Symbol Max Units Input Voltage VIN 7 V Power Dissipation PD Internally Limited W θJ A 65 63 50 60 °C/W Thermal Resistance Junction to Case SO-8 SOT-223 TO-220-X, TO-263-X θJ C 39 27 3 °C/W Operating Ambient Temperature Range TA -40 to +85 °C Operating Junction Temperature Range TJ -40 to +150 °C Storage Temperature Range TSTG -65 to +150 °C Lead Temperature (Soldering) 10 Sec. TLEAD 300 °C ESD Rating (Human Body Model) V ESD 4 kV Thermal Resistance Junction to Ambient SO-8(1) SOT-223 TO-220-X TO-263-X Note: (1) 1 square inch of FR-4, double sided, 1 oz. minimum copper weight. Electrical Characteristics Unless specified: VEN = VIN. Adjustable Option (VADJ > VTH(ADJ)): VIN = 2.2V to 5.5V and IO = 10µA to 1.5A. Fixed Options (VADJ = GND): VIN = (VO + 0.7V) to 5.5V and IO = 0A to 1.5A. Values in bold apply over the full operating temperature range. Parameter Symbol Test Conditions Min Typ Max Units 5.5 V VIN Supply Voltage Range VIN Quiescent Current IQ 2.2 VIN = 3.3V 0.75 1.75 mA VIN = 5.5V, VEN = 0V 10 35 µA VO +1% V VO Output Voltage(1) VO VIN = VO + 0.7V, IO = 10mA -1% -2% (Internal Fixed Voltage) +2% Line Regulation(1) REG(LINE) VIN = (VO + 0.25V) to 5.5V, IOUT = 10mA 0.035 0.3 % Load Regulation(1) REG(LOAD) VIN = VO + 0.7V 0.2 0.4 % VD IO = 10mA 2.5 10 mV Dropout Voltage(1)(2) 20 IO = 500mA 90 300 mV 400 2005 Semtech Corp. 2 www.semtech.com SC1565 POWER MANAGEMENT Electrical Characteristics (Cont.) Unless specified: VEN = VIN. Adjustable Option (VADJ > VTH(ADJ)): VIN = 2.2V to 5.5V and IO = 10µA to 1.5A. Fixed Options (VADJ = GND): VIN = (VO + 0.7V) to 5.5V and IO = 0A to 1.5A. Values in bold apply over the full operating temperature range. Parameter Symbol Test Conditions Min Typ Max Units 180 400 mV VO (Cont.) IO = 1A Dropout Voltage(1)(2) 500 IO = 1.5A 270 500 mV 600 Minimum Load Current(3) IO Current Limit ICL VIN = VO + 0.7V 1 10 µA 1.6 2.0 3.5 A 1.188 1.200 1.212 V ADJ Reference Voltage(1) VREF VIN = 2.2V, VADJ = VOUT, IO = 10mA 1.176 Adjust Pin Current(4) Adjust Pin Threshold(5) IADJ VADJ = VREF VTH(ADJ) 0.05 1.224 30 200 nA 0.20 0.40 V 1.5 10 µA EN Enable Pin Current IEN VEN = 0V, VIN = 3.3V Enable Pin Threshold VIH VIN = 3.3V VIL VIN = 3.3V 1.6 V 0.4 Over Temperature Protection High Trip level Hysteresis THI 170 °C THYST 20 °C Notes: (1) Low duty cycle pulse testing with Kelvin connections required. (2) Defined as the input to output differential at which the output voltage drops to 1% below the value measured at a differential of 0.7V. (3) Required to maintain regulation. Voltage set resistors R1 and R2 are usually utilized to meet this requirement. Adjustable versions only. (4) Guaranteed by design. (5) When VADJ exceeds this threshold, the “Sense Select” switch disconnects the internal feedback chain from the error amplifier and connects VADJ instead. 2005 Semtech Corp. 3 www.semtech.com SC1565 POWER MANAGEMENT Pin Configurations Ordering Information Device SC1565IS-X.XTR(1)(3) SC1565IS-X.XTRT(1)(3(6) SC1565IST-X.XTR(2)(3) SC1565IST-XXTRT(2)(3)(6) SO-8 SC1565IM-X.XTR(2)(4) SC1565IM-XXTRT(2)(4)(6) SC1565I5M-X.XTR(1)(4) SC1565I5MX.XTRT(1)(4)(6) SC1565IT-X.X(2)(5) SC1565IT-X.XT(2)(5)(6) SC1565I5T-X.X(1)(5) SOT-223 SC1565I5T-X.XT(1)(5)(6) TO-220-3 TO-220-5 SOT-223, TO-220-3 and TO-263-3 TO-220-5 and TO-263-5 PIN FUNCTION 1 VIN 2 GND 3 VO TAB is GND PIN FUNCTION 1 EN 2 VIN 3 GND 4 VO 5 AD J SO-8 SOT-223 TO-263-3 TO-263-5 TO-220-3 TO-220-5 Notes: (1) Where -X.X denotes voltage options. Available voltages are: 2.5V and 1.8V. Output voltage can be adjusted using external resistors, see Pin Descriptions on page 5. (2) Where -X.X denotes voltage options. Available voltages are: 2.5V and 1.8V. Output not adjustable. (3) Only available in tape and reel packaging. A reel contains 2500 devices. (4) Only available in tape and reel packaging. A reel contains 800 devices. (5) Only available in tube packaging. A tube contains 50 devices. (6) Lead free product. This product is fully WEEE and RoHS compliant. Pin Configurations (Cont.) TAB is GND TO-263-3 2005 Semtech Corp. P ackag e 4 TO-263-5 www.semtech.com SC1565 POWER MANAGEMENT Block Diagram * * * Not present on SOT-223, TO-220-3 or TO-263-3 Pin Descriptions Pin Name Pin Desciption AD J Thi s pi n, when grounded, sets the output voltage to that set by the i nternal feedback resi stors. If external feedback resistors are used, the output voltage will be (See Application Circuits on page 1): VO = 1.200 (R1 + R2) R2 Volts EN Enable Input. Pulling this pin below 0.4V turns the regulator off, reducing the quiescent current to a fraction of its operating value. The device will be enabled if this pin is left open. Connect to VIN if not being used. GND Reference ground. Use all four pins on the SO-8 device for heatsinking. Use the tab on the SOT-223, TO-220 and TO-263 devices for heatsinking. VIN Input voltage. For regulation at full load, the input to this pin must be between (VO + 0.7V) and 5.5V. Minimum VIN = 2.2V. VO The pin is the power output of the device. 2005 Semtech Corp. 5 www.semtech.com SC1565 POWER MANAGEMENT Typical Characteristics Dropout Voltage (IOUT = 1.5A) vs. Output Dropout Voltage (IOUT = 1A) vs. Output Voltage vs. Junction Temperature Voltage vs. Junction Temperature 600 500 550 450 500 400 TJ = 150°C 450 350 350 VD (mV) 400 VD (mV) Top to bottom: TJ = 150°C TJ = 25°C TJ = -40°C TJ = 25°C 300 250 200 300 250 200 150 150 TJ = -40°C 100 100 50 50 0 0 2.2 2.4 2.6 2.8 3.0 3.2 3.4 3.6 3.8 4.0 4.2 4.4 2.2 4.6 2.4 2.6 2.8 3.0 3.2 3.8 4.0 4.2 Output Voltage (2.5V) vs. Junction Voltage vs. Junction Temperature Temperature vs. Output Current 2.550 Top to bottom: TJ = 150°C TJ = 25°C TJ = -40°C 350 300 4.4 4.6 VIN = 3.2V 2.540 2.530 2.520 250 IO = 10mA 2.510 VO (V) VD (mV) 3.6 Dropout Voltage (IOUT = 0.5A) vs. Output 400 200 2.500 2.490 150 IO = 1.5A 2.480 100 2.470 50 2.460 2.450 0 2.2 2.4 2.6 2.8 3.0 3.2 3.4 3.6 3.8 4.0 4.2 4.4 -50 4.6 -25 0 25 2.550 2.540 50 75 100 125 150 TJ (°C) VOUT (V) Output Voltage (2.5V) vs. Junction Reference Voltage vs. Junction Temperature vs. Output Current Temperature vs. Output Current 1.225 VIN = 5.5V 1.220 2.530 VIN = 2.2V 1.215 2.520 1.210 IO = 10mA VREF (V) 2.510 VO (V) 3.4 VOUT (V) VOUT (V) 2.500 2.490 IO = 1.5A 2.480 IO = 10mA 1.205 1.200 1.195 IO = 1.5A 1.190 2.470 1.185 2.460 1.180 2.450 1.175 -50 -25 0 25 50 75 100 125 150 -50 TJ (°C) 2005 Semtech Corp. -25 0 25 50 75 100 125 150 TJ (°C) 6 www.semtech.com SC1565 POWER MANAGEMENT Typical Characteristics (Cont.) 1.225 Reference Voltage vs. Junction Quiescent Current vs. Temperature vs. Output Current Junction Temperature 600 VIN = 5.5V 1.220 590 1.215 580 1.210 570 IO = 10mA 1.205 IQ (µA) VREF (V) VIN = 3.3V 1.200 1.195 IO = 1.5A 1.190 560 550 540 530 1.185 520 1.180 510 1.175 500 -50 -25 0 25 50 75 100 125 150 -50 TJ (°C) -25 0 25 50 75 100 125 150 TJ (°C) Off-State Quiescent Current vs. Junction Temperature 10 9 VIN = 5.5V 8 IQ(OFF) (µA) 7 6 5 4 3 2 1 0 -50 -25 0 25 50 75 100 125 150 TJ (°C) 2005 Semtech Corp. 7 www.semtech.com SC1565 POWER MANAGEMENT Applications Information Introduction Thermal Considerations The SC1565 is intended for applications such as graphics cards where high current capability and very low dropout voltage are required. It provides a very simple, low cost solution that uses very little pcb real estate. Additional features include an enable pin to allow for a very low power consumption standby mode, and a fully adjustable output. The power dissipation in the SC1565 is approximately equal to the product of the output current and the input to output voltage differential: Component Selection PD ( MAX ) = (VIN PD ≈ (VIN − VOUT ) • I O The absolute worst-case dissipation is given by: ( MAX ) − VOUT ( MIN ) )• I O ( MAX ) + VIN ( MAX ) • I Q ( MAX ) Input capacitor: a 4.7µF ceramic capacitor is recommended. This allows for the device being some distance from any bulk capacitance on the rail. Additionally, input droop due to load transients is reduced, improving load transient response. Additional capacitance may be added if required by the application. For a typical scenario, VIN = 3.3V ± 5%, VOUT = 2.8V and IO = 1.5A, therefore: Output capacitor: a minimum bulk capacitance of 2.2µF, along with a 0.1µF ceramic decoupling capacitor is recommended. Increasing the bulk capacitance will improve the overall transient response. The use of multiple lower value ceramic capacitors in parallel to achieve the desired bulk capacitance will not cause stability issues. Although designed for use with ceramic output capacitors, the SC1565 is extremely tolerant of output capacitor ESR values and thus will also work comfortably with tantalum output capacitors. For reference, the phase-margin contour of Figure 1 can be used to choose an appropriate output capacitor for a given stability requirement. Using this figure, and assuming TA(MAX) = 70°C, we can calculate the maximum thermal impedance allowable to maintain TJ ≤ 150°C: VIN(MAX) = 3.465V, VOUT(MIN) = 2.744V and IQ(MAX) = 1.75mA, Thus PD(MAX) = 1.09W. R TH( J − A )(MAX ) = (T J( MAX ) − TA (MAX ) PD (MAX ) ) = (150 − 70 ) = 73.4° C / W . 109 This should be achievable for the SO-8 package using pcb copper area to aid in conducting the heat away, such as one square inch of copper connected to the ground pins of the device. The SOT-223, TO-220 and TO-263 packages would not require heatsinking. Internal ground/ power planes and air flow will also assist in removing heat. For higher ambient temperatures it may be necessary to use additional copper area. Noise immunity: in very electrically noisy environments, it is recommended that 0.1µF ceramic capacitors be placed from IN to GND and OUT to GND as close to the device pins as possible. External voltage selection resistors: the use of 1% resistors, and designing for a current flow ≥ 10µA is recommended to ensure a well regulated output (thus R2 ≤ 120kΩ). 2005 Semtech Corp. 8 www.semtech.com SC1565 POWER MANAGEMENT Applications Information (Cont.) Co=22uF, Stable Region: Unstable Region: Co=2.2uF, Stable Region: Unstable Region: 1.5mA 1.5mA 15mA 15mA Load Load 150mA 150mA 0.001 0.01 0.1 1 1.5A 1.5A 10 0.001 0.01 0.1 1 10 ESR(Ohms) ESR(Ohms) Co=220uF, Stable Region: Unstable Region: 1.5mA 15mA Load 150mA 0.001 0.01 0.1 1 1.5A 10 ESR(Ohms) Figure 1: Phase-margin Contour Plot 2005 Semtech Corp. 9 www.semtech.com SC1565 POWER MANAGEMENT Outline Drawing - SO-8 A D e N DIM E1 E 1 2 ccc C 2X N/2 TIPS .053 .069 .010 .004 .065 .049 .012 .020 .007 .010 .189 .193 .197 .150 .154 .157 .236 BSC .050 BSC .010 .020 .016 .028 .041 (.041) 8 0° 8° .004 .010 .008 A A1 A2 b c D E1 E e h L L1 N 01 aaa bbb ccc 2X E/2 e/2 B D DIMENSIONS MILLIMETERS INCHES MIN NOM MAX MIN NOM MAX aaa C SEATING PLANE h A2 A C A1 bxN bbb 1.35 1.75 0.25 0.10 1.65 1.25 0.31 0.51 0.25 0.17 4.80 4.90 5.00 3.80 3.90 4.00 6.00 BSC 1.27 BSC 0.25 0.50 0.40 0.72 1.04 (1.04) 8 0° 8° 0.10 0.25 0.20 h H C A-B D c GAGE PLANE 0.25 SEE DETAIL L (L1) A DETAIL SIDE VIEW 01 A NOTES: 1. CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES). 2. DATUMS -A- AND -B- TO BE DETERMINED AT DATUM PLANE -H3. DIMENSIONS "E1" AND "D" DO NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS. 4. REFERENCE JEDEC STD MS-012, VARIATION AA. Land Pattern - SO-8 X DIM (C) G DIMENSIONS INCHES MILLIMETERS C G P X Y Z Z Y (.205) .118 .050 .024 .087 .291 (5.20) 3.00 1.27 0.60 2.20 7.40 P NOTES: 1. THIS LAND PATTERN IS FOR REFERENCE PURPOSES ONLY. CONSULT YOUR MANUFACTURING GROUP TO ENSURE YOUR COMPANY'S MANUFACTURING GUIDELINES ARE MET. 2. REFERENCE IPC-SM-782A, RLP NO. 300A. 2005 Semtech Corp. 10 www.semtech.com SC1565 POWER MANAGEMENT Outline Drawing - SOT-223 Land Pattern - SOT-223 2005 Semtech Corp. 11 www.semtech.com SC1565 POWER MANAGEMENT Outline Drawing - T0-263-3 Minimum Land Pattern - TO-263-3 2005 Semtech Corp. 12 www.semtech.com SC1565 POWER MANAGEMENT Outline Drawing - TO-263-5 Minimum Land Pattern - TO-263-5 2005 Semtech Corp. 13 www.semtech.com SC1565 POWER MANAGEMENT Outline Drawing - TO-220-3 Outline Drawing - TO-220-5 Contact Information Semtech Corporation Power Management Products Division 200 Flynn Road, Camarillo, CA 93012 Phone: (805)498-2111 FAX (805)498-3804 2005 Semtech Corp. 14 www.semtech.com