SC2443

SC2443_08 SEMTECH | Alldatasheet

Document overview

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Technical content

Features

u Wide input voltage range: 4.7V to 16V u 0.5V feedback voltage for low-voltage outputs u Programmable frequency up to 1 MHz per phase u 2-Phase synchronous continuous conduction mode for high efficiency step-down converters u Out-of-phase operation for low input current ripples u Output source and sink currents u Fixed frequency peak current-mode control u 75mV/-110mV maximum current sense voltage u Inductor DCR current-sensing for low-cost applications u Dual outputs or 2-phase single output operation u Excellent current sharing between individual phases u Individual soft-start, overload shutdown and enable u External reference input for DDR applications u External synchronization u Industrial temperature range u 4mm X 4mm X1mm 24-lead MLPQ package

Description

The SC2443 is a high-frequency dual synchronous step-down switching power supply controller. It provides out-of-phase high-current output gate drives to all N-channel MOSFET power stages. The SC2443 operates in synchronous continuous-con - duction mode. Both phases are capable of maintaining regula - tion with sourcing or sinking load currents, making the SC2443 suitable for generating both VDDQ and the tracking VTT for DDR applications. The SC2443 employs fixed frequency peak current-mode con - trol for the ease of frequency compensation and fast transient response. The dual-phase step-down controllers of the SC2443 can be used to produce two individually controlled and regulated out- puts or a single output with shared current in each phase. The Step-down controllers operate from an input of at least 4.7V and are capable of regulating outputs as low as 0.5V Individual soft-start and overload shutdown timer is included in each step-down controller. The SC2443 implements hiccup overload protection. In single output current share configura - tion, the master timer controls the soft-start and overload shut- down functions of both controllers.

Applications

u Telecommunication power supplies u DDR memory power supplies u Graphic power supplies u Servers and base stations VOUT1 IN2- VP1 VINVINVOUT1 IN2- VP1 VIN IN1- SC2443 IN1- COMP1 SYNC AGND REF REFIN COMP2 IN2- CS2- CS2+ SS2/EN2 AVCC BST2 GDH2 GDL2 PGND PVCC GDL1GDH1 BST1 SS1/EN1 CS1+ CS1- ROSC IN1- VOUT2 VIN VP1 IN1- VP1 VIN VIN VIN SC2443 IN1- COMP1 SYNC AGND REF REFIN COMP2 IN2- CS2- CS2+ SS2/EN2 AVCC BST2 GDH2 GDL2 PGND PVCC GDL1GDH1 BST1 SS1/EN1 CS1+ CS1- ROSC VOUT1 VIN IN1- VOUT1 Dual Independent Outputs Single Output With Current Sharing

Pin Configuration Ordering Information Marking Information Notes: () Available in tape and reel only. A reel contains 3,000 devices. (2) Available in lead-free package only. Device is WEEE and RoHS compliant. (24-lead 4mm X 4mm X mm MLPQ) θJA = 29°C/W Device Package SC2443MLTRT (1,2) 24-lead 4mm X 4mm X mm MLPQ SC2443EVB Evaluation Board Top View 7 12 24 19 IN1- COMP1 SYNC REF AGND REFIN COMP2 IN2- CS2- CS2+ AVCC SS2/EN2 GDL1 PVCC PGND GDH2 GDL2 BST2 ROSC CS1- CS1+ SS1/EN1 GDH1 BST1 Marking for the 4 X 4mm MLPQ-24 package:

Recommended Operating ConditionsAbsolute Maximum Ratings Exceeding the above specifications may result in permanent damage to the device or device malfunction. Operation outside of the parameters specified in the Electrical Characteristics section is not recommended. 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) This device is ESD sensitive. Use of standard ESD handing precautions is required

Electrical Characteristics

(for <10ns @ freq. < 500kHz) SS1/EN1, SS2/EN2, SYNC Voltage ……………… -0.3 to 6V IN1-, IN2-, REF Voltage ………………… -0.3 to AVCC+ 0.3V REFIN , COMP1, COMP2 Voltage ………… -0.3 to AVCC+ 0.3V CS1+, CS1-, CS2+, CS2- Voltage ………… -0.3 to AVCC+ 0.3V Unless otherwise specified: AVCC = PVCC = 12V, VBST1 = VBST2 = 12V, SYNC = 0V, -40°C < TA = TJ < 85°C, ROSC =51.1kW. Parameter Symbol Conditions Min Typ Max Units Undervoltage Lockout AVCC Start Threshold AVCCTH AVCC rising 4.5 4.7 V AVCC Start Hysteresis AVCCHYST 170 mV AVCC Operating Current ICC 12 16 mA AVCC Quiescent Current in UVLO Iq AVCC = AVCCTH - 0.2V 1.7 mA Channel 1 Error Amplifier Non-inverting Input Voltage VIN1+ 0.49 0.5 0.51 V Non-inverting Input Voltage VIN1+ 0°C < TA = TJ < 70°C 0.4925 0.5 0.5075 V Non-inverting Input Line Regulation AVCCTH < AVCC < 15V 0.02 %/V Input Offset Voltage 1 mV Inverting Input Bias Current IIN1- -0.1 -0.25 µA Amplifier Transconductance GM1 260 µW-1 Amplifier Open Loop Gain AOL1 65 dB Amplifier Unity Gain Bandwidth 5 MHz COMP1 Switching Threshold VCS1+=VCS1- = 0, VSS1 Rising 2.2 V Amplifier Output Sink Current VIN1- = 1V, VCOMP1 = 2.5V 16 µA Amplifier Output Source Current VIN1- = 0V, VCOMP1 = 2.5V 12 µA

Electrical Characteristics (continued) Parameter Symbol Conditions Min Typ Max Units Channel 2 Error Amplifier Input Common-mode Range() 0 3 V Inverting Input Voltage Range() 0 AVCC V Input Offset Voltage .5 mV Non-inverting Input Bias Current IIN2+ -50 -380 nA Inverting Input Bias Current IIN2- -00 -250 nA Inverting Input Voltage for 2 phases Single Output Operation 2.5 V Amplifier Transconductance GM2 260 µW-1 Amplifier Open Loop Gain AOL2 65 dB Amplifier Unity Gain Bandwidth 5 MHz COMP2 Switching Threshold VCS2+=VCS2- = 0, VSS2 Rising 2.2 V Amplifier Output Sink Current VCOMP2 = 2.5V 6 µA Amplifier Output Source Current VCOMP2 = 2.5V 2 µA Oscillator Channel Frequency fCH, fCH2 450 500 550 kHz Synchronizing Frequency() 2.fCH kHz SYNC Input High Voltage .5 V SYNC Input Low Voltage 0.5 V Channel Maximum Duty Cycle DMAX, DMAX2 88 % Channel Minimum Duty Cycle DMIN, DMIN2 0 % Current Limit Comparator Input Common Mode Range 0 AVCC- V Cycle by cycle Peak Currentr Limit VILIM+ , VILIM2+ VCS- = VCS2- = 0.5V, Sourcing 60 75 90 mV Valley Current Overload Shutdown Threshold VILIM- , VILIM2- VCS- = VCS2- = 0.5V, Sinking -85 -0 -30 mV Positive Current sense Input Bias Current ICS+ , ICS2+ VCS+ = VCS- = 0 VCS2+ = VCS2- = 0 -0.7 -2 µA Negative Current sense Input Bias Current ICS- , ICS2- VCS+ = VCS- = 0 VCS2+ = VCS2- = 0 -0.7 -2 µA

Notes: () Guaranteed by design. Parameter Symbol Conditions Min Typ Max Units Gate Drivers High side Gate Driver Peak Source Current VBST, VBST2 = 2V .5 A High side Gate Driver Peak Sink Current VBST, VBST2 = 2V A Low side Gate Driver Peak Source Current AVCC = PVCC = 2V .5 A Low side Gate Driver Peak Sink Current AVCC = PVCC = 2V A Gate Drive Rise Time CL = 2200pF 20 ns Gate Drive Fall Time CL = 2200pF 20 ns Low side Gate Driver to High side Gate Driver Non-overlapping delay CL = 0 90 ns High side Gate Driver to Low side Gate Driver Non-overlapping delay CL = 0 90 ns Minimum On Time TA = 25°C 50 ns Soft Start, Overload Latchoff and Enable Soft Start Charging Current ISS , ISS2 VSS = VSS2 = .5V 2 µA Overload Enabling Soft Start Voltage VSS and VSS2 Rising 3.2 V Overload IN- Threshold VSS = 3.8V, VIN- falling 0.75VREF V Overload IN2- Threshold VSS2 = 3.8V, VIN2- falling 0.72 X V Soft Start Discharge Current ISS _DIS , ISS2_DIS VSS = VSS2 = 3.8V .4 µA Overload Recovery Soft Start Voltage VSSRCV , VSSRCV2 VSS and VSS2 Falling 0.3 0.5 0.7 V Gate Driver Disable SS/EN Voltage 0.7 0.9 V Gate Driver Enable SS/EN Voltage .2 .5 V Internal 0.5V Reference Buffer Output Voltage VREF IREF = -mA 490 500 50 mV Load Regulation 0 < IREF <-5mA 0.05 %/mA Electrical Characteristics (continued)

3.10 3.11 3.12 3.13 3.14 3.15 3.16 3.17 3.18 -40 25 85 496 498 500 502 504 506 508 510 512 -40 25 85 2.05 2.10 2.15 2.20 2.25 2.30 2.35 -40 25 85 499.0 499.5 500.0 500.5 501.0 501.5 502.0 -40 25 85 Typical Characteristics 4.49 4.50 4.51 4.52 4.53 4.54 4.55 -40 25 85 12.1 12.2 12.3 12.4 12.5 12.6 12.7 12.8 12.9 -40 25 85 1.55 1.60 1.65 1.70 1.75 1.80 1.85 -40 25 85 AVCC UVLO(V) UVLO Threshold vs. Temperature Temperature (OC) AVCC operation current vs. Temperature Temperature (OC) AVCC operation Current(mA) AVCC current in UVLO vs. Temperature AVCC Current in UVLO(mA) VREF(mV) VREF vs. Temperature Temperature (OC) COMP Sink/Source current vs. Temperature Temperature (OC) COMP SINK/SOURCE Current(uA) E/A GM vs. Temperature E/A GM(u W COMP Switching Threshold(V) COMP switching Threshold vs. Temperature Temperature (OC) Switching Frequency setting vs. Temperature Temperature (OC) Switching Frequency(KHz) Cycle by Cycle OCP threshold vs. TemperatureCycle by Cycle OCP Threshols(mV) SS/EN Threshold Voltage(V) SS/EN Threshold for Overload Hiccup vs. Temperature Temperature (OC) SS/EN Threshold for Gate Driver Enable / Disable vs. Temperature Temperature (OC) SS/EN Threshold Voltage(V) SS/EN Threshold Voltage(V) Temperature (OC) Temperature (OC) Temperature (OC) Temperature (OC) -15 -10 -40 25 85 SINK SOURCE 220 230 240 250 260 270 280 290 -40 25 85 ROSC = 5.KW 71.0 71.5 72.0 72.5 73.0 73.5 74.0 74.5 75.0 -40 25 85 0.80 0.85 0.90 0.95 1.00 1.05 1.10 1.15 1.20 1.25 1.30 -40 25 85 Enable Disable 0.42 0.44 0.46 0.48 0.50 0.52 0.54 0.56 0.58 -40 25 85 SS/EN Threshold for Overload Hiccup Recovery vs. Temperature

Typical Application Circuit Performance Circuit Conditions : Single output current share configuration as shown in page 5 Soft Start 0ms/DIV VIN 2V/DIV VOUT V/DIV COMP V/DIV EN/SS 2V/DIV Releasing SS/EN pin from GND VOUT V/DIV COMP V/DIV EN/SS 2V/DIV VIN 5V/DIV VOUT V/DIV GDL 5V/DIV EN/SS 2V/DIV VIN 5V/DIV Shuting down _ VIN ramp down ms/DIV VIN 2V/DIV VOUT V/DIV GDL 0V/DIV EN/SS 2V/DIV Pulling SS/EN pin to GND Gate Wavefroms GDH2 GDL2 0V/DIV GDH GDL 0V/DIV Output Ripple _ IOUT = 40A us/DIV VOUT 20mV/DIV Transient Response _ 0A ~ 30A OCP Trip _ IOUT = 56A VOUT 50mV/DIV VOUT 0.5V/DIV GDL 0V/DIV GDH 20V/DIV SS/EN 2V/DIV 0ms/DIV 0ms/DIV VIN 5V/DIV VOUT V/DIV GDL 0V/DIV EN/SS 2V/DIV 400us/DIV us/DIV GDH GDH2 0V/DIV 200us/DIV 400us/DIV Efficiency (2VIN to VOUT) IOUT(A) EFF (%) OCP Recovery to 30A loading VOUT 0.5V/DIV GDL 0V/DIV GDH 20V/DIV SS/EN 2V/DIV 20ms/DIV Releasing SS/EN pin from GND

Typical Application Circuit Performance Circuit Conditions : Dual independent outputs configuration as shown in page 7 Soft Start (VOUT) 0ms/DIV VIN 2V/DIV VOUT V/DIV COMP EN/SS 2V/DIV Soft Start (Both outputs) VOUT2 2V/DIV COMP2 V/DIV EN2/SS2 2V/DIV VIN 2V/DIV VOUT2 2V/DIV SS2/EN2 2V/DIV VOUT 0.5V/DIV SS/EN 2V/DIV Gate waveforms (VOUT_2 = 20A) us/DIV GDH GDL 0V/DIV GDH2 GDL2 0V/DIV Output Ripple (VOUT_20A) Output Ripple (VOUT2_20A) GDH2 GDL2 0V/DIV Transient Response (VOUT _ 2A ~ 7A) 200us/DIV VOUT 50mV/DIV OCP Trip (VOUT = 30A) VOUT2 50mV/DIV VOUT 0.5V/DIV GDH GDL 20V/DIV SS/EN 2V/DIV 0ms/DIV 20ms/DIV VOUT 50mV/DIV GDH GDL 0V/DIV us/DIV us/DIV 200us/DIV 400us/DIV Combined Efficiency (2VIN to VOUT & 2.5VOUT) IOUT(A) EFF (%) VOUT2 V/DIV GDL2 0V/DIV GDH2 20V/DIV SS2/EN2 2V/DIV 400us/DIV Soft Start (VOUT2) VOUT2 50mV/DIV Transient Response (VOUT2 _ 2A ~ 7A) OCP Trip (VOUT2 = 28A)

Pin # Pin Name Pin Function IN- Inverting Input of the Error Amplifier for the Step-down Controller . 2 COMP The Error Amplifier Output for Step-down Controller .

3 SYNC

Edge-triggered Synchronization Input. When not synchronized, tie this pin to a voltage above .5V or the ground. An external clock (frequency > frequency set with ROSC) at this pin synchronizes the controllers.

4 AGND Analog Signal Ground

5 REF Buffered Output of the Internal 0.5V Reference. The non-inverting input of the error amplifier for the step-down converter is internally connected to this pin 6 REFIN An external Reference voltage is applied to this pin.The non-inverting input of the error amplifier for the step-down converter 2 is internally connected to this pin. 7 COMP2 The Error Amplifier Output for Step-down Controller 2. 8 IN2- Inverting Input of the Error Amplifier for the Step-down Controller 2. Tie to AVCC for two-phase single output applications. 9 CS2- The Inverting Input of the Current-sense Amplifier/Comparator for the Controller 2. 0 CS2+ The Non-inverting Input of the Current-sense Amplifier/Comparator for the Controller 2. SS2/EN2 An external capacitor tied to this pin sets (i) the soft-start time (ii) output overload latch off time for step-down converter 2. Pulling this pin below 0.7V shuts off the gate drivers for the second controller. Leave open for two-phase single output applications. 2 AVCC Power Supply Voltage for the Analog Portion of the Controllers. 3 BST2 Bootstrapped Supply for the High-side Gate Drive 2. 4 GDH2 Gate Drive Output for the High-side N-channel MOSFET of Output 2. 5 GDL2 Gate Drive Output for the Low-side N-channel MOSFET of Output 2. 6 PGND Ground Supply for All the Gate drivers. 7 PVCC Power Supply Voltage for Low-side MOSFET Drivers. 8 GDL Gate Drive Output for the Low-side N-channel MOSFET of Output . 9 GDH Gate Drive Output for the High-side N-channel MOSFET of Output . 20 BST Bootstrapped Supply for the High-side Gate Drive . 2 SS/EN An external capacitor tied to this pin sets (i) the soft-start time (ii) output overload latch off time for buck converter . Pulling this pin below 0.7V shuts off the gate drivers for the first controller. 22 CS+ The Non-inverting Input of the Current-sense Amplifier/Comparator for the Controller .

23 CS- The Inverting Input of the Current-sense Amplifier/Comparator for the Controller

24 ROSC An external resistor connected from this pin to GND sets the oscillator frequency

THPAD Solder to the Analog ground plane of the PCB.

6 DSBL

0.72 VREFOUT

0.75 VREF

Figure 1. SC2443 Block Diagram

The SC2443 is a constant frequency 2-phase current-mode step-down PWM switching controller driving all N-channel MOSFET. The two channels of the controller operate at 80 degrees out-of-phase from each other. Since input currents are interleaved in a two-phase converter, input ripple current is lower and smaller input capacitor can be used for filtering. Also, with lower inductor current and smaller inductor ripple current per phase, overall I 2R losses are reduced. The SC2443 operates in synchronous continuous- conduction mode. It can be configured either as two independent step-down controllers producing two separate outputs or as a dual-phase single-output controller by tying the IN2- pin to VCC. In single output operation, the channel one error amplifier controls both channels and the channel two error amplifier is disabled. Soft-start and overload hiccup of both channels is synchronized to channel one. Frequency Setting and Synchronization The internal oscillator of the SC2443 runs at twice the phase frequency. The free-running frequency of the oscillator can be programmed with an external resistor from the ROSC pin to ground. The step-down controllers are capable of operating up to MHz. It is necessary to consider the operating duty-ratio before deciding the switching frequency. See Applications Information section for more details. When synchronized externally, the applied clock frequency should be twice the desired phase frequency. The synchronizing clock frequency should also be between 2 - 2.6 times the set free-running channel frequency. Control Loop The SC2443 uses peak current-mode control for fast transient response, ease of compensation and current sharing in single output operation. The low-side MOSFET of each channel is turned off at the falling-edge of the phase timing clock. After a brief non-overlapping time interval of 90ns, the high-side MOSFET is turned on. The phase inductor current ramps up. When the sensed inductor current reaches the threshold determined by the error amplifier output and compensation ramp, the high-side MOSFET is turned off. After a non-overlapping conduction time of 90ns, the low-side MOSFET is turned on. The supply voltages for the high-side gate drivers are obtained from two diode-capacitor bootstrap circuits. If the bootstrap capacitor is charged from VCC, the high- side gate drive voltage swing will be from approximately 2VCC to the ground. The power dissipated in the high- side gate driver is not higher with higher voltage swing because the gate-source voltage of the high-side MOSFET still swing from zero to VCC. The outputs of the low-side gate drivers swing from VCC to ground. The SC2443 has internal ramp-compensation to prevent sub-harmonic oscillation when operating above 50% duty cycle. There is enough ramp internally for a sensed voltage ripple between /4 to /3 of the full-scale sensed voltage limit of 75mV. The maximum sensed voltage limit is unaffected by the compensating ramp. Current-Sensing There are two ways to sense the inductor current for current-mode control with the SC2443. Since the peak inductor current corresponds to 75mV of sensed voltage (CS+ - CS-), resistor current sensing can be used at the output without resulting in excessive power dissipation. Although accurate and far easier to lay out than high-side resistor sensing, a pair of precision sense resistors adds cost to the converter. With proper RC filter, Inductor DCR sensing can also be used for SC2443 resulting in low cost and without extra power dissipation. Error Amplifiers In closed loop operation, the error amplifier output ranges from .V to 3.5V. The upper output operating range of either error amplifier is reserved for positive current- sense voltage (CS+ - CS-) and corresponds to positive (sourcing) output current. If the amplifier swings to its lower operating range, the amplifier will still modulate the high-side gate drive duty-ratio. However the peak current- sense voltage (hence the peak inductor current) will be limited to a negative value. The error amplifier output is about 2.2V when the peak sense-voltage is zero. The built-in offset in the current sense amplifier together with synchronous continuous-conduction mode of operation allows the SC2443 to regulate the output irrespective of the direction of the load current.

current reaching its current limit and the instant the converter shuts down. This is due to cycle skipping(a consequence of inductor current sense) reduces the actual operating frequency. The SS/EN pin can also be used as the enable input for that channel. Both the high-side and the low-side MOSFETs will be turned off if the SS/EN pin is pulled below 0.7V. Operating Frequency (fs) The switching frequency in the SC2443 is user- programmable. The advantages of using constant frequency operation are simple passive component selection and ease of feedback compensation. Before setting the operating frequency, the following trade-offs should be considered. ) Passive component size 2) Circuitry efficiency 3) EMI condition 4) Minimum switch on time and 5) Maximum duty ratio For a given output power, the sizes of the passive components are inversely proportional to the switching frequency, whereas MOSFET and Diodes switching losses are proportional to the operating frequency. Other issues such as heat dissipation, packaging and the cost issues are also to be considered. The frequency bands for signal transmission should be avoided because of EM interference. Minimum Switch On Time Consideration In the SC2443 the falling edge of the clock turns on the top MOSFET. The inductor current and the sensed voltage ramp up. After the sensed voltage crosses a threshold determined by the error amplifier output, the top MOSFET is turned off. The propagation delay time from the turn- on of the controlling FET to its turn-off is the minimum switch on time. The SC2443 has a minimum on time of about 50ns at room temperature. This is the shortest on interval of the controlling FET. The controller either does not turn on the top MOSFET at all or turns it on for at least 50ns. For a synchronous step-down converter, the operating duty cycle is VINVO / . So the required on time for the top MOSFET is ( )SFVINVO ×/ . If the frequency is set such that the required pulse width is less than 50ns, then the converter will start skipping cycles. Due to minimum on time limitation, simultaneously operating at Applications Information (continued) The non-inverting input of the first feedback amplifier is tied to the internal 0.5V voltage reference. Both the non- inverting and the inverting inputs of the second error amplifier are brought out as device pins so that the output of the second converter can be made to track the output of the first channel. For example in DDR applications, Channel can be used to generate VDDQ (2.5V) from the input (5V or 2V) and channel 2 is used to produce a tracking VTT (.25V) with VDDQ being its input. Current-Limit The maximum current sense voltage of +75mV is the cycle-by-cycle peak current limit when the load is drawing current from the converter. There is no cycle-by- cycle current limiting when the inductor current flows in the negative direction. However once the valley of the current sense voltage exceeds -0mV, the corresponding channel will undergo shutdown and restart (hiccup). Soft-Start and Overload Protection The undervoltage lockout circuit discharges the SS/EN capacitors. After VCC rises above 4.5V, the SS/EN capacitors are slowly charged by internal 2 mA current source. With internal PNP transistors, the SS/EN voltages clamp the error amplifier outputs. When the error amplifier output rises to 2.2V, the high-side MOSFET starts to switch. As the SS/ EN capacitor continues to be charged, the COMP voltage follows. The converter gradually delivers increasing power to the output. The inductor current follows the COMP voltage envelope until the output goes into regulation. The SS/EN clamp on COMP is then released. After the SS/EN capacitor is charged above 3.2V (high enough for the error amplifier to provide full load current), the overload detection circuit is activated. If the output voltage falls below 70% of its set value or the valley current-sense voltage exceeds -0mV, an overload latch will be set and both the top and the bottom MOSFETs will be turned off. The SS/EN capacitor is slowly discharged with an internal .4mA current sink. The overload latch is reset when the SS/EN capacitor is discharged below 0.5V. The SS/EN capacitor is then recharged with the 2uA current source and the converter undergoes soft-start. If overload persists, the SC2443 will undergo repetitive shutdown and restart. If the output is short-circuited, the inductor current will not increase indefinitely between the time the inductor

inversely proportional to the resistor value (Figure 2). Figure 2. Free running frequency vs. ROSC. is internally tied the 0.5V voltage reference output (Pin 5). operation of high frequency switching power converters. power ground to improve high frequency bypass.

Applications Information (continued) ground should be minimized. 7) Solder the bias decoupling capacitor right across the AVCC and analog ground AGND. 8) Place the inductor DCR sense components away from the power circuit and close to the corresponding CS+ and CS- pins. Use X7R type ceramic capacitor for the DCR sense capacitor because of their temperature stability. 9) Use an isolated local ground plane underneath the controller and tie it to the negative side of output capacitor bank. 0) Comp pin is sensitive to noise. Place compensation network components away from noise signal (i.e. gate driver signals, phase node) and close to corresponding Comp pin .

Evaluation Application Circuit _ Single Output, Current share configuration 12VIN R201K C171500uF/6.3V/FL R210K C242.2nF C3270uF/16V/OSCON Q6IPD06N03LA 1.5uH/1.8mR CS1- C1410uF/6.3V C16 1500uF/6.3V/FL R10 2R2 R4N.P. R31R 1uF C11 270uF/16V/OSCON C1910uF/6.3V R11 1VOUT/40A C13 N.P C12330pF IPD09N03LA CS1- IN1- C110uF/16V C91uF 12VIN C18N.P. SC2443 123456 13 14 15 16 17 18 IN1-COMP1SYNCAGNDREFREFIN COMP2 IN2- CS2- CS2+ SS2/EN2 AVCC BST2 GDH2 GDL2 PGND PVCC GDL1GDH1 BST1 SS1/EN1 CS1+ CS1- ROSC CS1+ R21 10R D21N4148C20 1uF R14N.P. Q3IPD06N03LA C82.2nF R18 C251uF 47K C722nF R610R C23100nF R1210K R131R C15 1500uF/6.3V/FL CS1+ C622pF R17 IPD06N03LA IPD09N03LA D11N4148 C2222pF R19560R IN1- C1010uF/16V C5100nF IPD06N03LA R1610R C21100nF R151.05K 12VIN C2270uF/16V/OSCON R8560R 1.5uH/1.8mR R5124K

Item Reference Quantity Description Package Part Vendor C,C0 2 6V X5R ceramic capacitor 206 0uF Murata

2 C2,C3,C 3 6V Aluminum solid capacitor _SEPC series 8 X 9mm 270uF Sanyo

3 C4,C9,C20,C25 4 6V X5R ceramic capacitor 0603 uF Murata

4 C5,C2,C23 3 6V X7R ceramic capacitor 0603 00nF Panasonic

5 C6,C22 2 25V X7R ceramic capacitor 0603 22pF Panasonic

6 C7 16V X7R ceramic capacitor 0603 22nF Panasonic

7 C8,C24 2 25V X7R ceramic capacitor 0603 2.2nF Panasonic

8 C2 25V X7R ceramic capacitor 0603 330pF Panasonic

9 C4,C9 2 6.3V X7R ceramic capacitor 206 0uF Murata 0 C5,C6,C7 3 6.3V Aluminum capacitor _ FL series 8 X .5mm 000uF Panasonic D,D2 2 Small signal diode SMD N448 Any 2 L,L2 2 SMD inductor 2.5 X 2.5 X 0mm .5uH/.8mR TRIO

3 Q,Q4 2 30V N Channel MOSFET D-pack IPD09N03LA Infineon

4 Q2,Q3,Q5,Q6 4 30V N Channel MOSFET D-pack IPD06N03LA Infineon

5 R,R7,R,

R7,R8 5 5% SMD resistor 0603 0R Any

6 R2,R2 2 5% SMD resistor 0603 0K Any

7 R3,R3 2 5% SMD resistor 0603 R Any

8 R5 % SMD resistor 0603 24K Any

9 R6,R6.R2 3 % SMD resistor 0603 0R Any

20 R8,R9 2 % SMD resistor 0603 560R Any

2 R9 5% SMD resistor 0603 47K Any

22 R0 5% SMD resistor 0603 2R2 Any

23 R5 % SMD resistor 0603 .05K Any

24 R20 % SMD resistor 0603 K Any

25 U Dual phase Sync. step down controller MLPQ-24 SC2443 SEMTECH Evaluation Board Bill of Materials Single Output Current Share Configuration

Evaluation Application Circuit_ Dual Independant Outputs N.P. IPD09N03LA R6124K C17N.P. R4N.P. SYNC R174.12K R240R R122R2 CS1+ IPD09N03LA C2422uF/10V/X7R C2922nF C16470pF CS1- Q6N.P. R9N.P. C10 1800uF/6.3V/FL C15 1500uF/16V/FL L12.2uH/2mR 12VIN 12VIN Q5IPD06N03LA C2122uF/10V/X7R 1800uF/6.3V/FL CS1+ 27pF C252.2nF C28N.P. C19100nF R190R R215K R221K R16N.P. C1410uF/16V R21N.P. C301uF C5100nF R80R L22.2uH/2mR R151R C122.2nF R101K R51.05K C722nF C20 N.P. C22 2200uF/6.3V/FL CS1- C110uF/16V 1N1- R1147K C41uF R130R D11N4148 12VIN R1420K C21500uF/16V/FL R10R C810uF/6.3V R70R C23 2200uF/6.3V/FL SC2443 123456 13 14 15 16 17 18 IN1-COMP1SYNCAGNDREFREFIN COMP2 IN2- CS2- CS2+ SS2/EN2 AVCC BST2 GDH2 GDL2 PGND PVCC GDL1GDH1 BST1 SS1/EN1 CS1+ CS1- ROSC R2310R R31R R180R Q2IPD06N03LA C26100nF IN1- C181uF C3N.P. D21N4148 R20100K R250R 2.5VOUT/20A C27470pF C131uF 1VOUT/20A C1110uF/6.3V

Item Reference Quantity Description Package Part Vendor C,C4 2 6V X5R ceramic capacitor 206 0uF Murata

2 C2,C5 2 6V Aluminum capacitor _FL series 0 X 20mm 500uF Panasonic

3 C4,C3,C8,

C30 4 6V X5R ceramic capacitor 0603 uF Murata

4 C5,C9,C26 3 6V X7R ceramic capacitor 0603 00nF Panasonic

5 C6 25V X7R ceramic capacitor 0603 27pF Panasonic

6 C7,C29 2 16V X7R ceramic capacitor 0603 22nF Panasonic

7 C8,C 2 6.3V X7R ceramic capacitor 206 0uF Murata 8 C9,C0 2 6.3V Aluminum capacitor _ FL series 0 X 6mm 800uF Panasonic 9 C2,C25 2 25V X7R ceramic capacitor 0603 2.2nF Panasonic

0 C6,C27 2 25V X7R ceramic capacitor 0603 470pF Panasonic

C2,C24 2 0V X7R ceramic capacitor 206 0uF Murata 2 C22,C23 2 6.3V Aluminum capacitor _ FL series 0 X 20mm 2200uF Panasonic

3 D,D2 2 Small signal diode SMD N448 Any

4 L,L2 2 Through hole inductor 2.2uH/2mR Any

5 Q,Q4 2 30V N Channel MOSFET D-pack IPD09N03LA Infineon

6 Q2,Q5 2 30V N Channel MOSFET D-pack IPD06N03LA Infineon

R,R7,R,R3, R8,R9,R24 R25 8 5% SMD resistor 0603 0R Any

8 R2 5% SMD resistor 0603 5K Any

9 R3,R5 2 5% SMD resistor 0603 R Any

20 R5 % SMD resistor 0603 .05K Any

2 R6 % SMD resistor 0603 24K Any

22 R0,R22 2 % SMD resistor 0603 K Any

23 R 5% SMD resistor 0603 47K Any

24 R2 5% SMD resistor 0603 2R2 Any

25 R4 5% SMD resistor 0603 20K Any

26 R7 % SMD resistor 0603 4.2K Any

27 R20 5% SMD resistor 0603 00K Any

28 R23 5% SMD resistor 0603 0R Any

29 U Dual phase Sync. step down controller MLPQ-24 SC2443 SEMTECH Evaluation Board Bill of Materials Dual Independent Output Configuration

Evaluation Application Circuit_ Dual Independant Outputs (Lower power application) D D C C B B A A A SC2443 Dual indepe ndant Outputs Tuesday, December 11, 2007 TitleSize Document Number Rev Date: Sheet of VIN 12VIN 1.5VOUT1.8VOUT 12VIN C722nF C301uF 1000uF/6.3V/FL SC2443 123456 13 14 15 16 17 18 IN1-COMP1SYNCAGNDREFREFIN COMP2 IN2- CS2- CS2+ SS2/EN2 AVCC BST2 GDH2 GDL2 PGND PVCC GDL1GDH1 BST1 SS1/EN1 CS1+ CS1- ROSC 27pF Q1FDS6982 R80R C11N.P C17N.P. R122R2 C27470pF R6102K R9604R 100nF/X7R C23 N.P L21.9uH/3.9mR R1147K R31R C24N.P R10R D11N4148 C110uF/16V C181uF C131uF C26100nF R250R C252.2nF C10 N.P R16N.P. C2922nF R4N.P. C28N.P. C1410uF/16V R52.05K C16470pF R240R D21N4148 R221K L11.9uH/3.9mR R190R R144.87K Q2FDS6982 R101K C2110uF/6.3V/X7R C19 100nF/X7R R21604R C122.2nFR151R R2047K C810uF/6.3V C22 1000uF/6.3V/FL R130R C41uF C2680uF/16V/FL R1810R R172.61K R710R C20 18pF R24.87K R2310R C15 680uF/16V/FL CS1+ CS1- CS1+CS1- 1N1- IN1- SYNC

Item Reference Quantity Description Package Part Vendor C,C4 2 6V X5R ceramic capacitor 206 0uF Murata 2 C2,C5 2 6V Aluminum capacitor _FL series 0 X 2.5mm 680uF Panasonic C30 4 6V X5R ceramic capacitor 0603 uF Murata 7 C8,C2 2 6.3V X7R ceramic capacitor 206 0uF Murata 8 C9,C22 2 6.3V Aluminum capacitor _ FL series 0 X 2.5mm 000uF Panasonic 9 C2,C25 2 25V X7R ceramic capacitor 0603 2.2nF Panasonic C20 25V X7R ceramic capacitor 0603 8pF Murata

2 D,D2 2 Small signal diode SMD N448 Any

3 L,L2 2 Through hole inductor .9uH/3.9mR Any

4 Q,Q2 2 30V N Channel MOSFET SO-8 FDS6982 Fairchild

5 R,R8,R3,

R9,R24,R25 6 5% SMD resistor 0603 0R Any 6 R2,R4 2 5% SMD resistor 0603 4.87K Any

7 R3,R5 2 5% SMD resistor 0603 R Any

8 R5 % SMD resistor 0603 2.05K Any

9 R6 % SMD resistor 0603 02K Any

20 R7,R8,R23 3 5% SMD resistor 0603 0R Any

2 R9,R2 2 5% SMD resistor 0603 604R Any

23 R,R20 2 5% SMD resistor 0603 47K Any

25 R7 % SMD resistor 0603 2.6K Any 26 U Dual phase Sync. step down controller MLPQ-24 SC2443 SEMTECH Evaluation Board Bill of Materials Dual Independent Output Configuration

© Semtech, Inc. All Rights Reserved. An ISO-registered company. Semtech cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Semtech product. No circuit patent licenses are implied. Semtech reserves the right to change the circuitry and specifications without notice at any time. Trademarks and Copyrights belong to their respective holders. © 2007 Semtech Corporation e bxN D/2 LxN INCHES .020 BSC b .007 bbb aaa N E L e D .012 .100 DIM A MIN .000 .031 0.50 2.80 0.30 2.55 .004 .004 .016 .157 .106 .020 .110 0.10 0.10 0.40 4.00 2.70

0.50 BSC

0.05 1.00 DIMENSIONS MIN 0.00 NOM (.008) .035 .001 MAX .002 .039 NOM 0.80 0.02 (0.20) 0.90 CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES). COPLANARITY APPLIES TO THE EXPOSED PAD AS WELL AS THE TERMINALS. NOTES: N PIN 1 INDICATOR 4.153.85 4.00 4.153.85.157 .152 .163 .152 .163 aaa C A C (LASER MARK) D E B A SEATING PLANE E/2 bbb C A B

COMPANY'S MANUFACTURING GUIDELINES ARE MET. 4.80.189Z K G ZH(C) X P FUNCTIONAL PERFORMANCE OF THE DEVICE. SHALL BE CONNECTED TO A SYSTEM GROUND PLANE. THERMAL VIAS IN THE LAND PATTERN OF THE EXPOSED PAD FAILURE TO DO SO MAY COMPROMISE THE THERMAL AND/OR THIS LAND PATTERN IS FOR REFERENCE PURPOSES ONLY. CONSULT YOUR MANUFACTURING GROUP TO ENSURE YOUR NOTES: DIM X Y H K P C G MILLIMETERSINCHES (3.95) .010 .033 .122 .020 .106 .106 (.156) 0.25 0.85 2.70 0.50 2.70 3.10 DIMENSIONS Semtech Corporation Power Management Products Division

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