150mA ULTRA LOW DROPOUT, LOW NOISE REGULATOR March 1, 2000 SC8863 TEL:805-498-2111 FAX:805-498-3804 WEB:http://www.semtech.com DESCRIPTION The SC8863 is a low dropout linear regulator that operates from a +2.5V to +5.5V input range and delivers up to 150mA. A PMOS pass transistor allows the low 110µA 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 powered shutdown, short circuit protection, thermal shutdown protection and reverse battery protection. The SC8863 comes in the tiny 5 lead SOT-23 package. FEATURES • Guaranteed 150 mA output current • Fixed or adjustable output • Very small external components • Low 75µVRMS output noise • Very low supply current • Thermal overload protection • Reverse battery protection • Low power shutdown • Surface mount packaging (5 pin SOT-23) • Full industrial temperature range APPLICATIONS • Battery Powered Systems • Cellular Telephones • Cordless Telephones • Personal Digital Assistants • Portable Instrumentation • Modems • PCMCIA cards ORDERING INFORMATION Part Number BLOCK DIAGRAM Package (1)(2) SC8863-XXXCSK SOT-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) Add suffix ‘TR’ for tape and reel. ABSOLUTE MAXIMUM RATINGS Parameter PIN CONFIGURATION Symbol Maximum Units Input Supply Voltage VIN -0.6 to +7 V Power Dissipation TA = 70°C PD 571 mW Thermal Resistance θJA 256 °C/W θJC 81 °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 ESD 1.25 kV 1 © 2000 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320 150mA ULTRA LOW DROPOUT, LOW NOISE REGULATOR SC8863 March 1, 2000 PIN DESCRIPTIONS Pin # Pin Name Description 1 EN Active high enable pin. Connect to VIN if not being used. 2 GND Ground pin. Can be used for heatsinking if needed. 3 IN Input pin. 4 OUT Regulator output, sourcing up to 150mA 5 SET 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 TYPICAL APPLICATION - INTERNALLY PRESET OUTPUT VOLTAGE U1 3 VIN > VOUT + VD(MAX) 1 SC8863 VIN EN C1 1uF Ceramic VO GND SET 4 VOUT @ IOUT up to 150mA 5 C2 1uF Ceramic 2 TYPICAL APPLICATION - EXTERNALLY SET OUTPUT VOLTAGE U1 3 VIN > VOUT + VD(MAX) (1) SC8863 VIN VO 4 VOUT @ IOUT up to 150mA R1 1 EN GND SET 5 2 C1 1uF Ceramic R2 10k C2 2.2uF Ceramic NOTES: (1) Select R1 and R2 such that the current flowing through them is ≥ 10µA (i.e. R2 ≤ 120kΩ). A value of 10kΩ is recommended for R2. Please see Component Selection - Externally Set Output. 2 © 2000 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320 150mA ULTRA LOW DROPOUT, LOW NOISE REGULATOR SC8863 March 1, 2000 ELECTRICAL CHARACTERISTICS Unless specified: VIN = 3.6V, VSET = GND, VEN = VIN, TA = 25°C. Values in bold apply over full operating ambient temperature range. Parameter Symbol Conditions Min Typ Max Units 5.5 V 130 µA IN Supply Voltage Range VIN Supply Current IQ 2.5 IOUT = 0mA 100 160 50mA ≤ IOUT ≤ 150mA 110 160 µA 200 VEN = 0V 0.0001 1 µA 2 OUT (1) Output Voltage (1) Line Regulation VOUT REG(LINE) IOUT = 1mA -2.0% 1mA ≤ IOUT ≤ 150mA, VOUT+1V ≤ VIN ≤ 5.5V -3.5% 2.5V ≤ VIN ≤ 5.5V, SET = OUT, IOUT = 1mA VOUT +2.0% V +3.5% 5 10 mV 12 (1) Load Regulation REG(LOAD) IOUT = 0mA to 50mA -10 -15 mV -20 IOUT = 0mA to 100mA -15 -20 mV -25 IOUT = 0mA to 50mA, SET = OUT -2.5 -7.5 mV -15.0 IOUT = 0mA to 100mA, SET = OUT -5 -15 mV -30 (1)(2) Dropout Voltage VD IOUT = 1mA 1.1 IOUT = 50mA 55 mV 90 mV 120 IOUT = 100mA 110 180 mV 240 Current Limit ILIM Output Voltage Noise en Power Supply Rejection Ratio PSRR 150 240 10Hz to 99kHz, IOUT = 50mA, COUT = 1µF 90 COUT = 100µF 75 f ≤ 1kHz 55 350 mA µVRMS dB 3 © 2000 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320 150mA ULTRA LOW DROPOUT, LOW NOISE REGULATOR SC8863 March 1, 2000 ELECTRICAL CHARACTERISTICS (Cont.) Unless specified: VIN = 3.6V, VSET = GND, VEN = VIN, TA = 25°C. Values in bold apply over full operating ambient temperature range. Parameter Symbol Conditions Min Typ Max Units EN EN Input Threshold VIH V 1.8 VIL (3) EN Input Bias Current IEN 0.4 EN = VIN 0 100 nA 200 SET Sense/Select Threshold VTH (1) SET Reference Voltage VSET (3) SET Input Leakage Current ISET 20 55 80 mV IOUT = 1mA 1.225 1.250 1.275 V 1mA ≤ IOUT ≤ 150mA, 2.5V ≤ VIN ≤ 5.5V 1.206 SET = 1.3V 1.294 0.015 2.500 nA 5.000 OVER TEMPERATURE PROTECTION High Trip Level Hysteresis THI 170 °C THYST 10 °C NOTE: (1) Low duty cycle pulse resting with Kelvin corrections required. (2) Defined as the input to output differential at which the output voltage drops 100mV below the value measured at a differential of 2V. (3) Guaranteed by design. 4 © 2000 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320 150mA ULTRA LOW DROPOUT, LOW NOISE REGULATOR SC8863 March 1, 2000 TYPICAL CHARACTERISTICS Output Voltage vs. Output Current 2.86 2.86 VIN = 3.6V TJ = 25°C 2.85 VIN = 3.6V 2.85 2.84 2.84 2.83 2.83 2.82 2.82 2.81 2.81 VOUT (V) VOUT (V) Output Voltage vs. Junction Temperature vs. Output Current 2.80 2.79 IO = 100mA IO = 150mA 2.79 2.78 2.78 2.77 2.77 2.76 2.76 2.75 2.75 2.74 IO = 1mA IO = 50mA 2.80 2.74 0 25 50 75 100 125 150 -50 -25 0 25 IOUT (mA) SET Reference Voltage vs. Output Current 1.275 75 100 125 SET Reference Voltage vs. Junction Temperature vs. Output Current 1.290 VIN = 3.6V TJ = 25°C 1.270 50 TJ (°C) VIN = 3.6V 1.280 1.265 1.270 1.260 1.255 VSET (V) VSET (V) 1.260 1.250 1.245 IO = 1mA IO = 50mA IO = 100mA 1.250 IO = 150mA 1.240 1.240 1.230 1.235 1.220 1.230 1.225 1.210 0 25 50 75 100 125 150 -50 -25 0 IOUT (mA) 75 100 125 Line Regulation vs. Junction Temperature 12 SET = GND 225 10 200 150 -40°C 25°C 125°C 125 100 75 50 REG(LINE) (mV) 175 VD (mV) 50 TJ (°C) Dropout Voltage vs. Output Current vs. Junction Temperature 250 25 VIN = 2.5V to 5.5V SET = OUT IOUT = 1mA 8 6 4 2 25 0 0 0 25 50 75 IOUT (mA) 100 125 150 -50 -25 0 25 50 75 100 125 TJ (°C) 5 © 2000 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320 150mA ULTRA LOW DROPOUT, LOW NOISE REGULATOR SC8863 March 1, 2000 TYPICAL CHARACTERISTICS (Cont.) Load Regulation (SET = OUT) vs. Junction Temperature Load Regulation (SET = GND) vs. Junction Temperature 20.0 50 VIN = 3.6V SET = GND 45 IOUT = 0mA to 150mA 40 IOUT = 0mA to 150mA 35 30 25 20 IOUT = 0mA to 100mA 15.0 REG(LOAD) (mV) REG(LOAD) (mV) VIN = 3.6V SET = OUT 17.5 12.5 10.0 7.5 IOUT = 0mA to 100mA 15 5.0 10 2.5 IOUT = 0mA to 50mA 5 0 IOUT = 0mA to 50mA 0.0 -50 -25 0 25 50 75 100 -50 125 -25 0 25 50 75 100 125 100 125 TJ (°C) TJ (°C) Supply Current vs. Output Current Supply Current vs. Junction Temperature 120 150 110 100 125 VIN = 3.6V IOUT = 150mA 90 100 70 IQ (µA) IQ (µA) 80 60 50 40 75 50 30 20 25 VIN = 3.6V TJ = 25°C 10 0 0 0 25 50 75 100 125 150 -50 0 25 50 75 TJ (°C) Current Limit vs. Junction Temperature Enable Input Threshold vs. Junction Temperature 350 2.0 VIN = 3.6V VIN = 3.6V 1.8 300 1.6 VIH, VIL (V) 250 ILIM (mA) -25 IOUT (mA) 200 150 1.4 VIH 1.2 1.0 VIL 100 0.8 50 0.6 0 0.4 -50 -25 0 25 50 TJ (°C) 75 100 125 -50 -25 0 25 50 75 100 125 TJ (°C) 6 © 2000 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320 150mA ULTRA LOW DROPOUT, LOW NOISE REGULATOR SC8863 March 1, 2000 TYPICAL CHARACTERISTICS (Cont.) Sense/Select Threshold vs. Junction Temperature Output Spectral Noise Density vs. Frequency 80 10 VIN = 3.6V SC8863-2.8 VIN = 3.6V IOUT = 50mA TJ = 25°C 70 √Hz) en (µV/√ VTH (mV) 60 50 1 COUT = 1µF 0.1 40 30 COUT = 100µF 0.01 20 -50 -25 0 25 50 75 100 125 0.1 1 10 TJ (°C) 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. 100 f (kHz) ing the bulk capacitance will further reduce output noise and improve the overall transient response. Input capacitor - Semtech recommends the use of a 1µF 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 VO = 1 .250 • 1 + R 2 1% tolerance resistors are recommended. The values of R1 and R2 should be selected such that the current flow through them is ≥ 10µA (thus R2 ≤ 120kΩ). At high input voltages and/or high output currents, staU1 3 SC8863 VIN VO 4 R1 1 Component Selection - General EN GND SET 5 2 Output capacitor - Semtech recommends a minimum capacitance of 1µF at the output with an equivalent series resistance (ESR) of <1Ω over temperature. Ceramic capacitors are ideal for this application. Increas- C1 1uF Ceramic R2 10k C2 2.2uF Ceramic Figure 1: Externally set output 7 © 2000 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320 150mA ULTRA LOW DROPOUT, LOW NOISE REGULATOR SC8863 March 1, 2000 bility may be improved by increasing C2 to 2.2µF and reducing R2 to 10kΩ. 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 ) − VO (MIN ) ) • I O ( MAX ) + VIN ( MAX ) • IQ ( MAX ) The junction temperature can be further reduced 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 θTH(J-A) to approximately 130°C/W and TJ(MAX) to approximately 110°C, for example. Lower junction temperatures improve overall output voltage accuracy. A sample pcb layout for the Internally Preset Output Voltage circuit on page 2 is shown in Figure 2 below. For all practical purposes, it can be reduced to: PD ( MAX ) = (VIN (MAX ) − VO (MIN ) ) • IO ( MAX ) Looking at a typical application: VIN(MAX) = 4.2V VO = 3V - 3.5% worst-case IO = 150mA TA = 85°C PD ( MAX ) = (4 . 2 − 2 . 895 ) • 0 . 150 = 196 mW Using this figure, we can calculate the maximum thermal impedance allowable to maintain TJ ≤ 150°C: θ ( J − A )( MAX ) = (T J ( MAX ) − TA ( MAX ) ) PD ( MAX ) = (150 − 85 ) = 332 °C / W 0 .196 With the standard SOT-23-5 Land Pattern shown at the end of this datasheet, and minimum trace widths, the thermal impedance junction to ambient for SC8863 is 256°C/W. Thus with no additional heatsinking, TJ(MAX) = 135°C. Top Copper 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 below 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 (and the capacitor from OUT to SET for adjustable applications) close to the device for optimal transient response and device behaviour. 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. Top Silk Screen Figure 2: Suggested pcb layout based upon internally preset output voltage application on page 2. 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. 8 © 2000 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320 150mA ULTRA LOW DROPOUT, LOW NOISE REGULATOR SC8863 March 1, 2000 DEVICE OUTLINE - SOT23-5 LAND PATTERN - SOT23-5 ECN 00-915 9 © 2000 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320