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150mA Ultra Low Dropout, Low Noise Regulator POWER MANAGEMENT Description The SC8863 is a low dropout linear regulator that operates from a +2.5V to +6.0V input range and delivers up to 150mA. A PMOS pass transistor allows the low 110A supply current to remain independent of load, making these devices ideal for battery operated portable equipment such as cellular phones, cordless phones and personal digital assistants. The SC8863 output voltage can be preset or adjusted with an external resistor divider. Other features include low power shutdown, short circuit protection, thermal shutdown protection and reverse battery protection. The SC8863 comes in the tiny 5 lead SOT-23 package (lead free, fully WEEE and RoHS compliant available) and the ultra low profile 5 lead TSOT-23. SC8863 Features Guaranteed 150mA output current Works with ceramic capacitors Fixed or adjustable output Very small external components Low 75VRMS output noise Very low supply current Thermal overload protection Reverse battery protection Low power shutdown Full industrial temperature range Very low profile packaging available (1mm max. height) Surface mount packaging (SOT-23-5 and TSOT-23-5) Applications Battery Powered Systems Cellular Telephones Cordless Telephones Personal Digital Assistants Portable Instrumentation Modems PCMCIA cards U1 VIN > VOUT + VD(MAX) 3 IN SC8863 OUT 4 VOUT @ IOUT up to 150mA Typical Application Circuits 1 C1 1uF Ceramic EN GND 2 SET 5 C2 1uF Ceramic Internally Preset Output Voltage U1 VIN > VOUT + VD(MAX) 3 IN SC8863 OUT 4 R1 VOUT @ IOUT up to 150mA 1 EN GND 2 SET 5 R1 VOUT = 1.250 * 1 + R2 R2 10k C2 2.2uF Ceramic C1 1uF Ceramic Externally Preset Output Voltage(1) Note: (1) Select R1 and R2 such that the current flowing through them is 10A (i.e. R2 120k). A value of 10k is recommended for R2. Please see Component Selection - Externally Set Output on page 7. Revision: November 8, 2005 1 www.semtech.com SC8863 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 EN, IN, OUT, SET to GND Output Short Circuit Duration Thermal Resistance, Junction to Ambient Thermal Resistance, Junction to Case Operating Ambient Temperature Range Operating Junction Temperature Range Storage Temperature Range Lead Temperature (Soldering) 10 sec Symbol VPIN tSC J A J C TA TJ TSTG TLEAD Maximum -0.3 to +7 Infinite 256 81 -40 to +85 -40 to +150 -65 to +150 300 Units V s C/W C/W C C C C Electrical Characteristics(1) Unless specified: VIN = 3.6V, VSET = GND, VEN = VIN, TA = 25C. Values in bold apply over full operating ambient temperature range. Parameter IN Supply Voltage Range Supply Current Symbol Test Conditions Min Typ Max Units VIN IQ IOUT = 0mA 2.5 100 6.0 130 160 V A 50mA IOUT 150mA 110 160 200 A V E N = 0V 0.0001 1 2 A OUT Output Voltage(2) VOUT IOUT = 1mA 1mA IOUT 150mA, VOUT + 1V VIN 5.5V Line Regulation(2) REG(LINE) 2.5V VIN 5.5V, VSET = VOUT, IOUT = 1mA -2.0% -3.5% 5 VOUT +2.0% +3.5% 10 12 Load Regulation(2) REG(LOAD) IOUT = 0mA to 50mA -10 -15 -20 IOUT = 0mA to 100mA -15 -20 -25 mV mV mV V 2005 Semtech Corp. 2 www.semtech.com SC8863 POWER MANAGEMENT Electrical Characteristics (Cont.)(1) Unless specified: VIN = 3.6V, VSET = GND, VEN = VIN, TA = 25C. Values in bold apply over full operating ambient temperature range. Parameter Load Regulation (Cont.)(2) Symbol REG(LOAD) Test Conditions IOUT = 0mA to 50mA, VSET = VOUT IOUT = 0mA to 100mA, VSET = VOUT Min Typ -2.5 Max -7.5 -15.0 Units mV -5 -15 -30 mV Dropout Voltage(2)(3) VD IOUT = 1mA IOUT = 50mA IOUT = 100mA 1.1 55 90 120 110 180 240 mV mV mV Current Limit Output Voltage Noise ILIM en PSRR 10Hz to 99kHz, IOUT = 50mA, COUT = 1F 10Hz to 99kHz, IOUT = 50mA, COUT = 100F f 1kHz 150 240 90 75 55 350 mA VRMS dB Power Supply Rejection Ratio EN EN Input Threshold VIH VIL 1.8 0.4 VEN = VIN 0 100 200 V EN Input Bias Current(4) IEN nA SET Sense/Select Threshold SET Reference Voltage(2) VTH V SET ISET IOUT = 1mA 1mA IOUT 150mA, 2.5V VIN 5.5V SET Input Leakage Current(4) Over Temperature Protection High Trip Level Hysteresis THI THYST 170 10 C C VSET = 1.3V 20 1.225 1.206 0.015 55 1.250 80 1.275 1.294 2.500 5.000 nA mV V Notes: (1) This device is ESD sensitive. Use of standard ESD handling precautions is required. (2) Low duty cycle pulse testing with Kelvin connections required. (3) Defined as the input to output differential at which the output voltage drops 100mV below the value measured at a differential of 2V. (4) Guaranteed by design. 2005 Semtech Corp. 3 www.semtech.com SC8863 POWER MANAGEMENT Pin Configuration Top View Ordering Information Part Number SC8863-XXXCSKTR(1)(2) SC8863-XXXCSKTRT(1)(2)(3) SC8863-XXXTSKTR(1)(2) SC8863-XXXEVB(4) P ackag e SOT-23-5 SOT-23-5 TSOT-23-5 N/A SOT-23-5 & TSOT-23-5 Notes: (1) Where -XXX denotes voltage options. Available voltages are: 2.50V (-250), 2.80V (-280), 3.00V (-300), and 3.30 (-330)V. (2) Only available in tape and reel packaging. A reel contains 3000 devices. (3) Lead free product. Fully WEEE and RoHS compliant. (4) Evaluation board for SC8863. Specify output voltage option and packaging when ordering. Block Diagram Pin Descriptions Pin 1 2 3 4 5 Pin Name Pin Function EN GND IN OUT SET Active high enable pin. Connect to VIN if not being used. Ground pin. Can be used for heatsinking if needed. Input pin. Regulator output, sourcing up to 150mA. Connecting this pin to ground results in the internally preset value for VOUT. Connecting to an external resistor divider changes VOUT to: R1 VOUT = 1 .250 * 1 + R2 2005 Semtech Corp. 4 www.semtech.com SC8863 POWER MANAGEMENT Typical Characteristics Output Voltage vs. Output Current 2.86 2.85 2.84 2.83 2.82 VOUT (V) VOUT (V) 2.81 2.80 2.79 2.78 2.77 2.76 2.75 2.74 0 25 50 75 IOUT (mA) 100 125 150 VIN = 3.6V TJ = 25C 2.86 2.85 2.84 2.83 2.82 2.81 2.80 2.79 2.78 2.77 2.76 2.75 2.74 -50 -25 0 25 50 75 100 125 TJ (C) IO = 1mA IO = 50mA IO = 100mA IO = 150mA Output Voltage vs. Junction Temperature vs. Output Current VIN = 3.6V SET Reference Voltage vs. Output Current 1.275 1.270 1.265 1.260 VSET (V) VSET (V) 1.255 1.250 1.245 1.240 1.235 1.230 1.225 0 25 50 75 IOUT (mA) 100 125 150 VIN = 3.6V TJ = 25C 1.290 1.280 1.270 1.260 1.250 1.240 1.230 1.220 1.210 SET Reference Voltage vs. Junction Temperature vs. Output Current VIN = 3.6V IO = 1mA IO = 50mA IO = 100mA IO = 150mA -50 -25 0 25 50 75 100 125 TJ (C) Dropout Voltage vs. Output Current vs. Junction Temperature 250 225 200 175 VD (mV) 150 125 100 75 50 25 0 0 25 50 75 IOUT (mA) 100 125 150 0 -50 -25 -40C 25C 125C Line Regulation vs. Junction Temperature 12 10 8 6 4 2 VIN = 2.5V to 5.5V SET = OUT IOUT = 1mA SET = GND REG(LINE) (mV) 0 25 TJ (C) 50 75 100 125 2005 Semtech Corp. 5 www.semtech.com SC8863 POWER MANAGEMENT Typical Characteristics (Cont.) Load Regulation (VSET = GND) vs. Junction Temperature 50 45 40 REG(LOAD) (mV) 35 30 25 20 15 10 5 0 -50 -25 0 25 TJ (C) 50 75 100 125 IOUT = 0mA to 50mA IOUT = 0mA to 100mA VIN = 3.6V SET = GND IOUT = 0mA to 150mA Load Regulation (VSET = VOUT) vs. Junction Temperature 20.0 17.5 15.0 REG(LOAD) (mV) 12.5 10.0 7.5 5.0 2.5 0.0 -50 -25 0 25 TJ (C) 50 75 100 125 IOUT = 0mA to 50mA IOUT = 0mA to 100mA VIN = 3.6V SET = OUT IOUT = 0mA to 150mA Supply Current vs. Output Current 120 110 100 90 80 IQ (A) 60 50 40 30 20 10 0 VIN = 3.6V TJ = 25C 0 25 50 75 IOUT (mA) 100 125 150 25 0 -50 -25 IQ (A) 70 100 75 50 125 150 Supply Current vs. Junction Temperature VIN = 3.6V IOUT = 150mA 0 25 TJ (C) 50 75 100 125 Current Limit vs. Junction Temperature 350 300 250 VIH, VIL (V) ILIM (mA) 200 150 100 50 0 -50 -25 0 25 TJ (C) 50 75 100 125 VIN = 3.6V 2.0 1.8 1.6 1.4 1.2 1.0 0.8 0.6 0.4 -50 Enable Input Threshold vs. Junction Temperature VIN = 3.6V VIH VIL -25 0 25 TJ (C) 50 75 100 125 2005 Semtech Corp. 6 www.semtech.com SC8863 POWER MANAGEMENT Typical Characteristics (Cont.) Sense/Select Threshold vs. Junction Temperature 80 70 60 VTH (mV) 50 40 30 20 -50 -25 0 25 TJ (C) 50 75 100 125 0.01 0.1 1 f (kHz) 10 100 1 COUT = 1F 10 Output Spectral Noise Density vs. Frequency SC8863-2.8 VIN = 3.6V IOUT = 50mA TJ = 25C VIN = 3.6V en (V/Hz) 0.1 COUT = 100F Applications Information Theory Of Operation The SC8863 is intended for applications where very low dropout voltage, low supply current and low output noise are critical. It provides a very simple, low cost solution that uses very little pcb real estate. Fixed output voltage options require the use of only two external capacitors for operation. Each voltage option has both fixed and adjustable output voltage modes. Grounding the SET pin (pulling it below the Sense/Select threshold of 55mV) will connect the internal resistor divider to the error amplifier resulting with the internally preset output voltage. If SET is pulled above this threshold, then the Sense/Select switch will connect the SET pin to the error amplifier. The output will be regulated such that the voltage at SET will equal VSET, the SET reference voltage (typically 1.250V). An active high enable pin (EN) is provided to allow the customer to shut down the part and enter an extremely low power Off-state. A logic Low signal will reduce the supply current to 0.1nA. Component Selection - General Output capacitor: Semtech recommends a minimum capacitance of 1F at the output with an equivalent series resistance (ESR) of <1 over temperature. Ceramic capacitors are ideal for this application. Increasing the bulk capacitance will further reduce 2005 Semtech Corp. 7 C1 1uF Ceramic output noise and improve the overall transient response. Input capacitor: Semtech recommends the use of a 1F ceramic capacitor at the input. 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. Component Selection - Externally Set Output Please refer to Figure 1 below. The output voltage can be externally adjusted anywhere within the range from 1.25V to (VIN(MIN) - VD(MAX)). The output voltage will be in accordance with the following equation: R1 VOUT = 1.250 * 1 + R2 U1 3 IN SC8863 OUT 4 R1 1 EN GND 2 SET 5 R2 10k C2 2.2uF Ceramic Figure 1: Externally set output www.semtech.com SC8863 POWER MANAGEMENT Applications Information (Cont.) 1% tolerance resistors are recommended. The values of R1 and R2 should be selected such that the current flow through them is 10A (thus R2 120k). At high input voltages and/or high output currents, stability may be improved by increasing C2 to 2.2F and reducing R2 to 10k. See "Component Selection - General" for input capacitor requirements. Thermal Considerations The worst-case power dissipation for this part is given by: PD( MAX ) = (VIN(MAX ) - VOUT (MIN ) ) * IOUT (MAX ) + VIN( MAX ) * IQ(MAX ) With the standard SOT-23-5/TSOT-23-5 Land Pattern shown at the end of this datasheet, and minimum trace widths, the thermal impedance junction to ambient for SC8863 is 256C/W. Thus with no additional heatsinking, TJ(MAX) = 135C. The junction temperature can be reduced further by the use of larger trace widths, and connecting pcb copper area to the GND pin (pin 2), which connectes directly to the device substrate. Adding approximately one square inch of pcb copper to pin 2 will reduce TH(J-A) to approximately 130C/W and TJ(MAX) to approximately 110C, for example. Lower junction temperatures improve overall output voltage accuracy. A sample pcb layout for the Internally Preset Output Voltage circuit on page 1 is shown in Figure 2 on page 9. Layout Considerations While layout for linear devices is generally not as critical as for a switching application, careful attention to detail will ensure reliable operation. See Figure 2 on page 9 for a sample layout. 1) Attaching the part to a larger copper footprint will enable better heat transfer from the device, especially on PCBs where there are internal ground and power planes. 2) Place the input and output capacitors close to the device for optimal transient response and device behavior. 3) Connect all ground connections directly to the ground plane. If there is no ground plane, connect to a common local ground point before connecting to board ground. For all practical purposes, it can be reduced to: PD(MAX ) = (VIN( MAX ) - VOUT (MIN ) ) * IOUT (MAX ) Looking at a typical application: VIN(MAX) = 4.2V VOUT = (3 - 3.5%) = 2.895V worst-case IOUT = 150mA TA = 85C This gives us: PD( MAX ) = (4.2 - 2.895 ) * 0.150 = 196mW Using this figure, we can calculate the maximum thermal impedance allowable to maintain TJ 150C: ( J- A )(MAX ) = (T J(MAX ) - TA (MAX ) ) PD(MAX ) = (150 - 85) = 332C / W 0.196 2005 Semtech Corp. 8 www.semtech.com SC8863 POWER MANAGEMENT Applications Information (Cont.) Top Copper Top Silk Screen Figure 2: Suggested pcb layout based upon internally preset output voltage application on page 1. Notes: (1) All vias go to the ground plane. (2) Copper area on pin 2 is recommended, but not required. Connect to the ground plane with a via or vias. Marking Information Top Mark SOT-23-5 Bottom Mark 8XXX yyww yyww = Date code (example: 0108 for week 8 of 2001) 8 = 8863 in SOT-23-5 XXX = voltage option (examples: 8280 = SC8863-280CSK) Top Mark TSOT-23-5 Bottom Mark T8XX yyww yyww = Date code (example: 0108 for week 8 of 2001) T8 = 8863 in TSOT-23-5 XX = voltage option (examples: T828 = SC8863-280TSK) 2005 Semtech Corp. 9 www.semtech.com SC8863 POWER MANAGEMENT Outline Drawing - SOT-23-5 Outline Drawing - TSOT-23-5 2005 Semtech Corp. 10 www.semtech.com SC8863 POWER MANAGEMENT Land Pattern - SOT-23-5 & TSOT-23-5 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. 11 www.semtech.com |
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