SC283

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Technical content

Features

VIN Range: 2.9 – 5.5V VOUT Selectable: 0.8 - 3.3V Up to 1.8A Output Current for Each Channel Ultra-Small Footprint, <1mm Height Solution 2.5MHz Switching Frequency Efficiency Up to 93% Low Output Noise Across Load Range Excellent Transient Response Start Up into Pre-Bias Output 100% Duty-Cycle Low Dropout Operation <1µA Shutdown Current Internal Soft Start Input Under-Voltage Lockout Output Over-Voltage, Current Limit Protection Over-Temperature Protection Adjustable Output Voltage 2mm x 3mm x 0.8mm thermally enhanced MLPQ-W18 package -40 to +85°C Temperature Range Pb-Free product. RoHS/WEEE and Halogen Free com - pliant

Applications

Description

The SC283 is a dual channel 1.8A synchronous step- down regulator designed to operate with an input voltage range of 2.9 to 5.5 Volts. Each channel offers fifteen pre-determined output voltages via four control pins programmable from 0.8 to 3.3 Volts. The control pins allow for on-the-fly voltage changes, enabling system designers to implement dynamic power savings. The SC283 is also capable of adjusting the output voltage via an external resistor divider. The device operates with a fixed 2.5MHz oscillator frequency, allowing the use of small surface mount external components. Connecting CTL0 — CTL3 to logic low forces the device into shutdown mode reducing the supply current to less than 1µA. Connecting any of the control pins to logic high enables the converter and sets the output voltage according to Table 1. Other features include under- voltage lockout, soft-start to limit inrush current, and over-temperature protection. The SC283 is available in a thermally-enhanced, 2mm x 3mm x 0.8mm MLPQ-W18 package and has a rated temperature range of -40 to +85°C. Typical Application Circuit www.semtech.com1

© 2010 Semtech Corp. Pin Configuration Ordering Information Device Package SC283WLTRT(2)(3) 2mm x 3mm x 0.8mm MLPQ-W18 SC283EVB(4) Evaluation Board Notes: (1) Calculated from package in still air, mounted to 3” x 4.5” , 4 layer FR4 PCB with thermal vias under the exposed pad per JESD51 standards. (2) Available in tape and reel only. A reel contains 3,000 devices. (3) Pb-Free product. RoHS/WEEE and Halogen Free compliant. (4) Please specify the default VOUTA & VOUTB when ordering. Table 1 – Output Voltage Settings CTL3_ CTL2_ CTL1_ CTL0_ Output Voltage 0 0 0 0 Shutdown 0 0 0 1 0.80 0 0 1 0 1.00 0 0 1 1 1.025 0 1 0 0 1.05 0 1 0 1 1.20 0 1 1 0 1.25 0 1 1 1 1.30 1 0 0 0 1.50 1 0 0 1 1.80 1 0 1 0 2.20 1 0 1 1 2.50 1 1 0 0 2.60 1 1 0 1 2.80 1 1 1 0 3.00 1 1 1 1 3.30 2mm x 3mm x 0.8mm MLPQ-W18 θJA = 65°C/W (1) Marking Information Marking for 2mm x 3mm MLPQ-W 18 Lead Package: yw = Datecode (Reference Package Marking Design Guidelines, Appendix A) xxx = Semtech Lot number (Example: 901) www.semtech.com2

© 2010 Semtech Corp.

Electrical Characteristics

Exceeding the absolute maximum ratings may result in permanent damage to the device and/or device malfunction. Operation outside of the parameters specified in the Electrical Characteristics section is not recommended. Notes: (5) Calculated from package in still air, mounted to 3” x 4.5” , 4 layer FR4 PCB with thermal vias under the exposed pad per JESD51 standards. (6) Tested according to JEDEC standard JESD22-A114-B. Recommended Operating Conditions Supply Voltage VINA and VINB …………………… 2.9 to 5.5V Maximum Output Current for each channel ………… 1.8A Thermal Resistance, Junction to Ambient(5) ………… 65 °C/W Maximum Junction Temperature …………………… +150°C Storage Temperature Range ………………… -65 to +150 °C Thermal Information VINA and VINB Supply Voltages ………………… -0.3 to 6.0V LXA, LXB Voltage …. . -1 to VIN+1V, -3V (20ns Max), 6V Max VOUTA, VOUTB Voltage …………………… -0.3 to VIN+0.3V CTLxA/B pins Voltages ………………… -0.3 to VIN+0.3V Unless specified: VINA= VINB= 5.0V, VOUTA= VOUTB=1.50V, CINA=CINB=10µF, COA=COB= 22µF, L= 2.2µH, -40°C≤ TJ≤ +125 °C. Unless otherwise noted typical values are TA= +25 °C. Parameter Symbol Conditions Min Typ Max Units Under-Voltage Lockout UVLO Rising VINA, VINB 2.65 2.75 2.85 V Hysteresis 240 300 mV Output Voltage Tolerance(7) ΔVOUT Channel A & B; VIN= 2.9 – 5.5V; IOUT=0A -2.0 +2.0 % Current Limit ILIMIT Channel A & B; Peak LX current 2.25 3.0 3.75 A Supply Current IQ Channel A & B; No load, Per channel 10 mA Shutdown Current ISHDN CTL0-3= GND, Per channel 1 10 µA High Side Switch Resistance(8) RDSON_P Channel A & B; ILX= 100mA, TJ= 25 °C 95 mΩ Low Side Switch Resistance(8) RDSON_N Channel A & B; ILX= -100mA, TJ= 25 °C 65 LX Leakage Current(8) ILK(LX) Channel A & B; VIN= 5.5V; LX= 0V; CTL0-3= GND 1 10 µA Channel A & B; VIN= 5.5V; LX= 5.0V; CTL0-3= GND -10 -1 Load Regulation ΔVLOAD-REG Channel A & B; VIN= 5.0V; IOUT=1mA – 1.8A ±0.5 % Oscillator Frequency fOSC Channel A & B 2.125 2.500 2.875 MHz Soft-Start Time tSS Channel A & B; IOUT= 1.8A 850 µs Foldback Holding Current ICL_HOLD Average LX Current, VOUT=1.5V 240 mA Average LX Current, VOUT=3.3V 130 mA CTLx Input Current(8) ICTL_ Channel A & B; CTL0-3=VIN or GND -2.0 2.0 µA CTLx Input High Threshold VCTLx_HI Channel A & B 1.2 V Absolute Maximum Ratings www.semtech.com3

© 2010 Semtech Corp. Parameter Symbol Conditions Min Typ Max Units CTLx Input Low Threshold VCTLx_LO Channel A & B 0.4 V VOUT Over Voltage Protection VOVP Channel A & B 115 % Thermal Shutdown Temperature TSD Channel A & B(9) 160 °C Thermal Shutdown Hysteresis TSD_HYS Channel A & B(9) 10 °C Electrical Characteristics (continued) Notes: (7) The “Output Voltage Tolerance” includes output voltage accuracy, voltage drift over temperature and the line regulation. (8) The negative current means the current flows into the pin and the positive current means the current flows out from the pin. (9) The thermal shutdown for both Channel A and B is independent from each other. www.semtech.com4

© 2010 Semtech Corp. Typical Characteristics Efficiency vs. Load Current Total Loss (Per Channel) vs. Load Current Load Regulation Circuit Conditions: CIN= 10uF/6.3V; COUT= 22uF/6.3V, Unless otherwise noted, L= 2.2uH (TOKO: 1127AS-2R2M). Dropout Voltage in 100% Duty Cycle OperationDropout Voltage of 100% Duty Cycle Operation 100 150 200 250 300 350 400 450 500 Output Current (A) Dropout Voltage (mV) TA= 25° C L= 1071AS-2R2M (DCR= 60m_max) L= 1127AS-2R2M (DCR=48m_max) UVLO Rising Threshold VariationUVLO Rising Threshold Variation -1.0% -0.8% -0.6% -0.4% -0.2% 0.0% 0.2% 0.4% 0.6% 0.8% 1.0% -40 -15 10 35 60 85 Ambient Temperature (° C) Variation IOUT= 0A UVLO Hysteresis Variation -5% -4% -3% -2% -1% -40 -15 10 35 60 85 Ambient Temperature (° C) Variation IOUT= 0A UVLO Hysteresis Variation Efficiency 60% 65% 70% 75% 80% 85% 90% 95% 100% Output Current (A) Efficiency (%) VIN=5.0V;VOUT=3.3V TA=25° C VIN=5.0V;VOUT=1.5V VIN=3.3V;VOUT=1.5V Total Loss 200 400 600 800 1000 Output Current (A) Loss (mW) TA=25° C VIN=5.0V;VOUT=3.3V VIN=5.0V;VOUT=1.5V VIN=3.3V;VOUT=1.5V Load Regulation -1.0% -0.8% -0.6% -0.4% -0.2% 0.0% 0.2% 0.4% 0.6% 0.8% 1.0% Output Current (A) Load Regulation TA=25° C VIN=5.0V;VOUT=3.3V VIN=5.0V;VOUT=1.5V VIN=3.3V;VOUT=1.5V www.semtech.com5

© 2010 Semtech Corp. Line Regulation Line Regulation vs. Temperature RDS(ON) Variation vs. Input Voltage RDS(ON) Variation vs. Temperature Switching Frequency Variation vs. Input Voltage Switching Frequency Variation vs. Temperature RDSON (P & N) Variation over Line -10% -5% 10% 15% 20% 25% 30% Input Voltage (V) Variation ILX= ±100mA TA= 25° C N-Channel P-Channel RDSON (P & N) Variation Over Temperature -20% -15% -10% -5% 10% 15% 20% -40 -15 10 35 60 85 Ambient Temperature (° C) Variation VIN= 5.0V ILX= ±100mA N-Channel P-Channel Switching Frequency Variation over Line -5% -4% -3% -2% -1% Input Voltage (V) Variation IOUT= 0A TA= 25° C VOUT= 3.3V VOUT= 1.5V Line Regulation ove Line -1.0% -0.8% -0.6% -0.4% -0.2% 0.0% 0.2% 0.4% 0.6% 0.8% 1.0% Input Voltage (V) Regulation IOUT= 0A TA= 25° C VOUT= 3.3V VOUT= 1.5V Line Regulation over Temperature -1.0% -0.8% -0.6% -0.4% -0.2% 0.0% 0.2% 0.4% 0.6% 0.8% 1.0% -40 -15 10 35 60 85 Ambient Temperature (° C) Regulation VOUT= 1.5V IOUT= 0A Switching Frequency Variation -1.0% -0.8% -0.6% -0.4% -0.2% 0.0% 0.2% 0.4% 0.6% 0.8% 1.0% -40 -15 10 35 60 85 Ambient Temperature (° C) Variation VIN= 5.0V IOUT= 0A Typical Characteristics (continued) Circuit Conditions: CIN= 10uF/6.3V; COUT= 22uF/6.3V, Unless otherwise noted, L= 2.2uH (TOKO: 1127AS-2R2M). www.semtech.com6

© 2010 Semtech Corp. Output Voltage Ripple (VOUT=1.5V) Output Voltage Ripple (VOUT=3.3V) Output Voltage Ripple (VOUT=1.5V) Output Voltage Ripple (VOUT=3.3V) VOUT 10mV/div VLX 2V/div ILX 1A/div 500ns/div Output Voltage Ripple (VOUT=1.5V) VIN=3.3V IOUT=1.8A Typical Waveforms Circuit Conditions: CIN= 10uF/6.3V; COUT= 22uF/6.3V, L= 2.2uH (TOKO: 1127AS-2R2M). VOUT 10mV/div VLX 2V/div 500ns/div Output Voltage Ripple (VOUT=1.5V) VIN=5.0V IOUT=1.8A ILX 1A/div VOUT 10mV/div VLX 2V/div 500ns/div Output Voltage Ripple (VOUT=3.3V) VIN=5.0V IOUT=0A ILX 0.5A/div VOUT 10mV/div VLX 2V/div 500ns/div Output Voltage Ripple (VOUT=3.3V) VIN=5.0V IOUT=1.8A ILX 1A/div VOUT 100mV/div IOUT 1A/div 50µs/div Transient Response (VOUT=1.5V) VIN=5.0V IOUT=0A to 1A VOUT 100mV/div IOUT 500mA/div 50µs/div Transient Response (VOUT=3.3V) VIN=5.0V IOUT=0A to 1A Transient Response (VOUT=1.5V; 0A to 1A to 0A) Transient Response (VOUT=3.3V; 0A to 1A to 0A) www.semtech.com7

© 2010 Semtech Corp. VOUT 0.5V/div 50µs/div Start Up (VOUT=1.5V) VIN=5.0V ROUT=1k VCTLx 2V/div VIN 2V/div Typical Waveforms (continued) Circuit Conditions: CIN= 10uF/6.3V; COUT= 22uF/6.3V, L= 2.2uH (TOKO: 1127AS-2R2M). VOUT 0.5V/div 200µs/div Start Up (VOUT=1.5V) VIN=5.0V ROUT=0.83 (1.8A) VCTLx 2V/div VIN 2V/div VOUT 0.5V/div 200µs/div Start Up (VOUT=1.5V), EN=VIN VIN 2V/div VIN=5.0V ROUT=1k VOUT 0.5V/div 200µs/div Start Up (VOUT=1.5V), EN=VIN VIN 2V/div VIN=5.0V ROUT=0.83 (1.8A) VOUT 1V/div 100µs/div Start Up (VOUT=3.3V) VIN=5.0V ROUT=1k VCTLx 2V/div VIN 2V/div VOUT 1V/div 200µs/div Start Up (VOUT=3.3V) VIN=5.0V ROUT=1.83 (1.8A) VCTLx 2V/div VIN 2V/div Start Up (Enable)(VOUT=1.5V) Start Up (Power up VIN=VCTLx) (VOUT=1.5V) Start Up (Enable)(VOUT=1.5V) Start Up (Power up VIN=VCTLx) (VOUT=1.5V) Start Up (Enable)(VOUT=3.3V) Start Up (Enable)(VOUT=3.3V) www.semtech.com8

© 2010 Semtech Corp. Typical Waveforms (continued) Circuit Conditions: CIN= 10uF/6.3V; COUT= 22uF/6.3V, L= 2.2uH (TOKO: 1127AS-2R2M). Shutdown (Disable)(VOUT=1.5V) Shutdown (Disable)(VOUT=3.3V) 200µs/div Shutdown-Disable (1.5V) VOUT 1V/div VCTLx 2V/div VIN 2V/div VIN=5.0V ROUT=1.5 200µs/div Shutdown-Disable (3.3V) VOUT 1.5V/div VCTLx 2V/div VIN 2V/div VIN=5.0V ROUT=3.3 VOUT 1.5V/div 200µs/div Start Up (VOUT=3.3V), EN=VIN VIN 2V/div VIN=5.0V ROUT=1k VOUT 1.5V/div 200µs/div Start Up (VOUT=3.3V), EN=VIN VIN 2V/div VIN=5.0V ROUT=1.83 (1.8A) Start Up (Power up VIN=VCTLx) (VOUT=3.3V) Start Up (Power up VIN=VCTLx) (VOUT=3.3V) www.semtech.com9

© 2010 Semtech Corp. Pin Descriptions Pin # Pin Name Pin Function 1 VINA Channel A. Input supply voltage for the converter power stage and internal circuitry. 2 LXA Switching node of Channel A - connect an inductor between this pin and the output capacitor. 3, 13, T1 GNDA Channel A. Ground connection for converter power stage and internal circuitry. 4, 12, T2 GNDB Channel B. Ground connection for converter power stage and internal circuitry.

5 CTL3B

Channel B. Control bit 3 - see Table 1 for decoding. This pin has a 1 MΩ internal pulldown resistor. This resis - tor is switched in circuit whenever the pin voltage is below the input high threshold, or when the part is in undervoltage lockout.

6 CTL2B

Channel B. Control bit 2 - see Table 1 for decoding. This pin has a 1 MΩ internal pulldown resistor. This resis - tor is switched in circuit whenever the pin voltage is below the input high threshold, or when the part is in undervoltage lockout.

7 CTL1B

Channel B. Control bit 1 - see Table 1 for decoding. This pin has a 1 MΩ internal pulldown resistor. This resis - tor is switched in circuit whenever the pin voltage is below the input high threshold, or when the part is in undervoltage lockout.

8 CTL0B

Channel B. Control bit 0 - see Table 1 for decoding. This pin has a 1 MΩ internal pulldown resistor. This resis - tor is switched in circuit whenever the pin voltage is below the input high threshold, or when the part is in undervoltage lockout. 9 VOUTB Output voltage sense pin of Channel B. 10 VINB Channel B. Input supply voltage for the converter power stage and internal circuitry. 11 LXB Switching node of Channel B - connect an inductor between this pin and the output capacitor.

14 CTL3A

Channel A. Control bit 3 - see Table 1 for decoding. This pin has a 1 MΩ internal pulldown resistor. This resis - tor is switched in circuit whenever the pin voltage is below the input high threshold, or when the part is in undervoltage lockout.

15 CTL2A

Channel A. Control bit 2 - see Table 1 for decoding. This pin has a 1 MΩ internal pulldown resistor. This resis - tor is switched in circuit whenever the pin voltage is below the input high threshold, or when the part is in undervoltage lockout.

16 CTL1A

Channel A. Control bit 1 - see Table 1 for decoding. This pin has a 1 MΩ internal pulldown resistor. This resis - tor is switched in circuit whenever the pin voltage is below the input high threshold, or when the part is in undervoltage lockout.

17 CTL0A

Channel A. Control bit 0 - see Table 1 for decoding. This pin has a 1 MΩ internal pulldown resistor. This resis - tor is switched in circuit whenever the pin voltage is below the input high threshold, or when the part is in undervoltage lockout. 18 VOUTA Output voltage sense pin of Channel A. www.semtech.com10

© 2010 Semtech Corp. Block Diagram Control Logic Plimit Amp Current Amp PWM Comp Error Amp 500mV Ref CTL1 CTL2 CTL3 VOUT PGND LX PVIN Voltage Select AVIN AGND Oscillator & Slope Generator CTL0 Plimit Comp GNDA VINA LXA CTL3A CTL2A CTL1A CTL0A VOUTA Control Logic Plimit Amp Current Amp PWM Comp Error Amp 500mV Ref CTL1 CTL2 CTL3 VOUT PGND LX PVIN Voltage Select AVIN AGND Oscillator & Slope Generator CTL0 Plimit Comp GNDB VINB LXB CTL3B CTL2B CTL1B CTL0B VOUTB www.semtech.com11

© 2010 Semtech Corp. Applications Information (continued) vs. Output Voltage Over-Voltage Protection In the event of a 15% over-voltage on the output, the PWM drive is disabled leaving the LX pin floating. Soft-Start The soft-start mode is activated after VIN reaches its UVLO and one or more CTL pins are set high to enable the part. A thermal shutdown event will also activate the soft start sequence. Soft-start mode controls the maximum current during startup thus limiting inrush current. The PMOS current limit is stepped through four soft start levels of approximately 20%, 25%, 40%, & 100%. Each step is main- tained for 200μs following an internal reference start up duration of 50μs giving a total nominal startup period of 850μs. During startup, the chip operates by controlling the inductor current swings between 0A and current limit. If at any time VOUT reaches 86% of the target or at the end of the soft-start period, the SC283 will switch to PWM mode operation. Figure 5 shows the typical diagram of soft start operation. The SC283 is capable of starting up into a pre-biased output. When the output is precharged by another supply rail, the SC283 will not discharge the output during the soft start interval. Shut Down When all CTL pins of each channel are low, the channel will run in shutdown mode, drawing less than 1μA from the input power supply. The internal switches and bandgap voltage will be immediately turned off. Thermal Shutdown The device has a thermal shutdown feature to protect the SC283 if the junction temperature exceeds 160°C. During thermal shutdown, the on-chip power devices are disabled, tri-stating the LX output. When the temperature drops by 10°C, it will initiate a soft start cycle to resume normal operation. Inductor Selection The SC283 converter has internal loop compensation. The compensation is designed to work with an output filter corner frequency of less than 40kHz for a V IN of 5V and 50KHz for a VIN of 3.3V over any operating condition. The corner frequency of the output filter is shown in Equation OUT C CL f 1 (3) Values outside this range may lead to instability, malfunction, or out-of-specification performance. In general, the inductance is chosen by making the inductor ripple current to be less than 30% of maximum load current. When choosing an inductor, it is important to consider the change in inductance with DC bias current. The inductor saturation current is specified as the current at which the inductance drops a specific percentage from the nominal value. This is approximately 30%. Except for short-circuit or other fault conditions, the peak current must always be less than the saturation current specified by the manufacturer. The peak current is the maximum load current plus one half of the inductor ripple current at the maximum input voltage. Load and/or line transients can cause the peak current to exceed this level for short durations. Maintaining the peak current below the inductor saturation specification keeps the inductor ripple current and the output voltage ripple at acceptable levels. Manufacturers often provide graphs of actual inductance and saturation characteristics versus applied inductor current. The saturation characteristics of the inductor can vary significantly with core temperature. Core and ambient temperatures should be considered when examining the core saturation characteristics. When the inductance has been determined, the DC resistance (DCR) must be examined. The efficiency that can be achieved is dependent on the DCR of the inductor. The lower values give higher efficiency. The RMS DC current rating of the inductor is associated with losses in the copper windings and the resulting temperature rise of the inductor. This is usually specified as the current which produces a 40˚C temperature rise. Most copper windings are rated to accommodate this temperature rise above maximum ambient. Magnetic fields associated with the output inductor can interfere with nearby circuitry. This can be minimized by the use of low noise shielded inductors which use the www.semtech.com14

© 2010 Semtech Corp. Applications Information (continued) minimum gap possible to limit the distance that magnetic fields can radiate from the inductor. However shielded inductors typically have a higher DCR and are thus less efficient than a similarly sized non-shielded inductor. Final inductor selection depends on various design considerations such as efficiency, EMI, size, and cost. Table 2 lists the manufacturers of recommended inductor options. The saturation characteristics and DC current ratings are also shown. Manufacturer Part Number L (μH) DCR Max (Ω) Rated Current (A) L at Rated Current (μH) Dimen- sions LxWxH (mm) TOKO TOKO TOKO Panasonic Table 2 – Recommended Inductors COUT Selection The internal voltage loop compensation in the SC283 limits the minimum output capacitor value to 22µF if using a 2.2µH inductor or 44µF if using a 1µH inductor. This is due to its influence on the the loop crossover frequency, phase margin, and gain margin. Increasing the output capacitor above this minimum value will reduce the crossover frequency and provide greater phase margin. The total output capacitance should not exceed 50µF to avoid any start-up problems. For most typical applications it is recommended to use an output capacitance of 22µF to 44µF. When choosing the output capacitor’s capacitance, verify the voltage derating effect from the capacitor vendor’s data sheet. Capacitors with X7R or X5R ceramic dielectric are recommended for their low ESR and superior temperature and voltage characteristics. Y5V capacitors should not be used as their temperature coefficients make them unsuitable for this application. The output voltage droop due to a load transient is deter- mined by the capacitance of the ceramic output capacitor. The ceramic capacitor supplies the load current initially until the loop responds. Within a few switching cycles the loop will respond and the inductor current will increase to match the required load. The output voltage droop during the period prior to the loop responding can be related to the choice of output capacitor by the relationship from Equation 4. OSCDROOP LOAD OUT fV IC ⋅ ∆⋅= 3 (4) The output capacitor RMS ripple current may be calculated from Equation 5. ( ) −⋅= INOSC OUTMAXINOUT RMSCOUT VfL VVVI 1 (5) Table 3 lists the manufacturers of recommended output capacitor options. Manufacturer Part Nunber Value (μF) Type Rated Voltage (VDC) Value at 3.3V (μF) Dimensions LxWxH (mm) Murata (EIA:0805) Murata (EIA:0805) Murata (EIA:0805) Murata (EIA:1206) Table 3 – Recommended Capacitors CIN Selection The SC283 source input current is a DC supply current with a triangular ripple imposed on it. To prevent large input voltage ripple, a low ESR ceramic capacitor is required. A minimum value of 10μF should be used. It is important to consider the DC voltage coefficient charac - teristics when determining the actual required value. It should be noted a 10µF, 6.3V, X5R ceramic capacitor with 5V DC applied may exhibit a capacitance as low as 4.5µF. www.semtech.com15

© 2010 Semtech Corp. Applications Information (continued) To estimate the required input capacitor, determine the acceptable input ripple voltage and calculate the minimum value required for CIN from Equation 6. OSC OUT IN OUT IN OUT IN fESRI V V V V V C ⋅  −∆  − (6) The input capacitor RMS ripple current varies with the input and output voltage. The maximum input capacitor RMS current is found from Equation 7.  −= IN OUT IN OUT RMSCIN V V V VI 1)( (7) The input voltage ripple and RMS current ripple are at a maximum when the input voltage is twice the output voltage or 50% duty cycle. The input capacitor provides a low impedance loop for the edges of pulsed current drawn by the PMOS switch. Low ESR/ESL X5R ceramic capacitors are recommended for this function. To minimise stray inductance ,the capacitor should be placed as closely as possible to the VIN and GND pins of the SC283. www.semtech.com16

© 2010 Semtech Corp. Outline Drawing – 2x3 MLPQ-W18 Land Pattern – 2x3 MLPQ-W18 2.001.90 2.10 NOTES: bbb C A B aaa C 0.08 0.136 0.00 0.70 0.3860.286 0.05 0.80 (0.20) 0.10 0.55 2.90 0.70 0.80 3.00 3.10

0.40 BSC

0.375 0.425 0.475 A COPLANARITY APPLIES TO THE EXPOSED PAD AS WELL AS THE TERMINALS.2. CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES).1. DIMENSIONS e bbb aaa DIM N L E D A MILLIMETERS MAXMIN NOM B N PIN 1 INDICATOR (LASER MARK) C b 0.15 0.20 0.25 PLANE SEATING D E A1A2 A e/2 e bxN LxN E/2 NE ND 2 0.850 2X E1 1.700 D/2 2.001.90 2.10 NOTES: bbb C A B aaa C 0.08 0.136 0.00 0.70 0.3860.286 0.05 0.80 (0.20) 0.10 0.55 2.90 0.70 0.80 3.00 3.10 0.375 0.425 0.475 A COPLANARITY APPLIES TO THE EXPOSED PAD AS WELL AS THE TERMINALS.2. CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES).1. DIMENSIONS e bbb aaa DIM N L E D A MILLIMETERS MAXMIN NOM B N PIN 1 INDICATOR (LASER MARK) C b 0.15 0.20 0.25 PLANE SEATING D E A1A2 A e/2 e bxN LxN E/2 NE ND 2 0.850 2X E1 1.700 D/2 www.semtech.com19

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Phone: (805) 498-2111 Fax: (805) 498-3804 www.semtech.com Contact Information SC283 © 2010 Semtech Corp. © Semtech 2010 All rights reserved. Reproduction in whole or in part is prohibited without the prior written consent of the copyright owner. The information presented in this document does not form part of any quotation or contract, is believed to be accurate and reliable and may be changed without notice. No liability will be accepted by the publisher for any consequence of its use. Publication thereof does not convey nor imply any license under patent or other industrial or intellectual property rights. Semtech assumes no responsibility or liability whatsoever for any failure or unexpected operation resulting from misuse, neglect improper installation, repair or improper handling or unusual physical or electrical stress including, but not limited to, exposure to parameters beyond the specified maximum ratings or operation outside the specified range. SEMTECH PRODUCTS ARE NOT DESIGNED, INTENDED, AUTHORIZED OR WARRANTED TO BE SUITABLE FOR USE IN LIFE-SUPPORT APPLICATIONS, DEVICES OR SYSTEMS OR OTHER CRITICAL APPLICATIONS. INCLUSION OF SEMTECH PRODUCTS IN SUCH AP- PLICATIONS IS UNDERSTOOD TO BE UNDERTAKEN SOLELY AT THE CUSTOMER’S OWN RISK. Should a customer purchase or use Semtech products for any such unauthorized application, the customer shall indemnify and hold Semtech and its officers, em- ployees, subsidiaries, affiliates, and distributors harmless against all claims, costs damages and attorney fees which could arise. www.semtech.com20