SEMTECH SC196

SC196 1.5A Synchronous Buck Converter with Integrated Power Devices POWER MANAGEMENT Description Features The SC196 is a synchronous step-down converter with ‹ Up to 95% efŢ ciency integrated power devices designed for use in applications ‹ V adjustable from less than 0.8V to V OUT IN using a single-cell Li-ion battery. Its wide input voltage ‹ Output current — 1.5A range also makes it suitable for use in systems with Ţ xed ‹ Input range — 2.5V to 5.5V 3.3V or 5V supply rails available. The switching frequency is ‹ Quiescent current — 17μA nominally set to 1MHz, allowing the use of small inductors ‹ Fixed 1MHz frequency or 750kHz to 1.25MHz and capacitors. The current rating of the internal MOSFET synchronized operation switches allows a DC output current of 1.5A. ‹ PSAVE operation to maximize efŢ ciency at light loads ‹ Shutdown current <1μA The output voltage is set by connecting a resistor divider ‹ Fast transient response from the Ţ lter inductor to the feedback pin. See the ‹ 100% duty cycle in dropout SC196A for pin-programmable output voltages. ‹ Soft-start ‹ Over-temperature and short-circuit protection The SC196 has a ţ exible clocking methodology that ‹ Lead-free package — MLPD10-UT, 3 x 3 x 0.6 mm allows it to be synchronized to an external oscillator or controlled by the internal oscillator. The device operates in either forced PWM mode or in PSAVE mode. If PSAVE Applications mode is enabled, the part will automatically enter PFM at ‹ Cell phones light loads to maintain maximum efŢ ciency across the full ‹ Wireless communication chipset power load range. ‹ Personal media players ‹ Microprocessor/DSP core/IO power For noise sensitive applications, PSAVE mode can be ‹ PDAs and handheld computers disabled by synchronizing to an external oscillator or ‹ WLAN peripherals pulling the SYNC/PWM pin high. Shutdown turns off all ‹ USB powered modems the control circuitry to achieve a typical shutdown current ‹ 1 Li-Ion or 3 NiMH/NiCd powered devices of 0.1μA. Typical Application Circuit V OUT L1 V IN <0.8V to V IN 4.7μH 2.5V to 5.5V 1.5A SC196 VIN LX C FB1 VOUT C PVIN IN R 10pF FB1 10μF MODE ADJ C OUT R FB2 EN 22μF SYNC/PWM PGND GND February 8, 2007 www.semtech.com 1 SC196 POWER MANAGEMENT PRELIMINARY Absolute Maximum Rating Exceeding the speciŢ cations below may result in permanent damage to the device or device malfunction. Operation outside of the parameters speciŢ ed in the Electrical Characteristics section is not recommended. Parameter Symbol Maximum Units Input Supply Voltage V -0.3 to 7 V IN Logic Inputs V -0.3 to V +0.3, 7V Max V N IN (N=SYNC/PWM, EN, MODE) Output Voltage V -0.3 to V +0.3, 7V Max V OUT IN ADJ Input V -0.3 to V +0.3, 7V Max V ADJ IN LX Voltage V -1 to V +1, 7V Max V LX IN (1) Thermal Impedance Junction to Ambient θ 40 °C/W JA VOUT Short-Circuit to GND t Continuous s SC Operating Ambient Temperature Range T -40 to +85 °C A Storage Temperature T -65 to +150 °C S Junction Temperature T -40 to +150 °C J Peak IR Reţ ow Temperature T 260 °C PKG (2) ESD Protection Level V 2kV ESD 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) Tested according to JEDEC standard JESD22-A114-B. Electrical Characteristics Unless otherwise noted: V = 3.6V, V = 1.8V, EN = V , SYNC/PWM = V , MODE = V , T = -40 to 85°C. Typical values are at T = 25°C. IN OUT IN IN IN A A Parameter Symbol Conditions Min Typ Max Units Input Voltage Range V 2.5 5.5 V IN UVLO Threshold (upper) V 2.18 2.3 2.45 V UVL UVLO Hysteresis V 150 mV UVLHYS Output Voltage Range V 0.8 V V OUT IN FB Voltage Tolerance V V = 2.5V to 5.5V, I = 0mA to 1.5A 0.485 0.5 0.515 V FB IN OUT Load Regulation (PWM) V I = 0mA to 1.5A ±0.5 ±1 % OUT LOAD OUT SYNC/PWM=GND,C = 22μF, OUT PSAVE Regulation V ±2 ±3 % OUT PSAVE V = 2.5V to 5.5V, I = 0mA to 1.5A IN OUT P-Channel Current Limit I V =2.5V to 5.5V 1.96 2.8 3.57 A LIM(P) IN SYNC/PWM = GND, I = 0A, OUT Quiescent Current I 17 28 μA Q V = 1.04 x V OUT OUT(Programmed) Shutdown Current I EN = GND, LX = OPEN 0.1 1 μA SD © 2007 Semtech Corp. www.semtech.com 2 SC196 POWER MANAGEMENT PRELIMINARY Electrical Characteristics (Cont.) Parameter Symbol Conditions Min Typ Max Units P-Channel On Resistance R I = 100mA 0.275 Ω DSP LX N-Channel On Resistance R I = 100mA 0.165 Ω DSN LX LX Leakage Current PMOS I LX = GND, EN = GND 0.1 2 μA LXP LX Leakage Current NMOS I LX = 3.6V, EN = GND -2 0.1 μA LXN Oscillator Frequency f 0.85 1.0 1.15 MHz OSC SYNC Frequency (upper) f 1.25 MHz SYNCU SYNC Frequency (lower) f 750 kHz SYNCL Start-Up Time t 5ms START Thermal Shutdown T 145 °C SD Thermal Shutdown Hysteresis T 10 °C SD-HYS (1) Logic Input High V 1.2 V IH (1) Logic Input Low V 0.4 V IL (1) Logic Input Current High I -2 0.1 2 μA IH (1) Logic Input Current Low I -2 0.1 2 μA IL Note: (1) For EN, SYNC/PWM, MODE © 2007 Semtech Corp. www.semtech.com 3 SC196 POWER MANAGEMENT PRELIMINARY Pin ConŢ guration Ordering Information DEVICE PACKAGE (1)(2) SC196ULTRT MLPD-UT10 3x3x0.6 SC196EVB Evaluation Board Ordering Information Notes: PVIN 1 10 LX 1) Lead-free packaging only. This product is fully WEEE and RoHS compliant. 2) Available in tape and reel only. A reel contains 3000 devices. TOP VIEW VIN 2 9 PGND SYNC/PWM 3 8 GND EN 4 7 MODE T VOUT56 ADJ MLPD-UT: 3X3X0.6, 10 LEAD Marking Information 196 yyww xxxx yy = two digit year of manufacture ww = two digit week of manufacture xxxx = lot number © 2007 Semtech Corp. www.semtech.com 4 SC196 POWER MANAGEMENT PRELIMINARY Pin Descriptions Pin # Pin Name Pin Function Input supply voltage connection to switching FETs — connect the input capacitor between this 1 PVIN pin and PGND directly. 2 VIN Input supply voltage for control circuits Oscillator synchronization input. Tie to V for forced PWM mode or GND to allow the part to 3 IN SYNC/PWM enter PSAVE mode at light loads. Apply an external clock signal for frequency synchronization. Enable digital input; a high input enables the SC196, a low disables and reduces quiescent cur- 4 EN rent to less than 1μA. In shutdown, LX becomes high impedance. Regulated output voltage sense pin — connect to the output capacitor allowing sensing of the 5 VOUT output voltage. Output Voltage Adjust and feedback compensation pin - connect resistor divider between this 6 ADJ pin and GND to set the desired output voltage level. 7 MODE MODE select pin — MODE = V to select 100% duty cycle function, MODE = GND to disable IN this function. 8 GND Ground 9 PGND Power Ground 10 LX Inductor connection to the switching FETs THERMAL Pad for heatsinking purposes — not connected internally. Connects to ground plane using T PAD multiple vias. © 2007 Semtech Corp. www.semtech.com 5 SC196 POWER MANAGEMENT PRELIMINARY Block Diagram Plimit Amp 1 PVIN Current Amp EN 4 SYNC OSC & Slope 3 /PWM Generator Control 10 LX Logic PWM Comp PSAVE Error Amp 500mV Comp Nlimit Amp Ref 9 PGND 7 MODE 2 VIN 8 GND 5 VOUT ADJ 6 © 2007 Semtech Corp. www.semtech.com 6 SC196 POWER MANAGEMENT PRELIMINARY Applications Information SC196 Detailed Description Table 1 — Recommended ADJ Resistor Combinations The SC196 is a synchronous step-down Pulse Width V (V) R (kΩ)R (kΩ) OUT FB2 FB1 Modulated (PWM), DC-DC converter utilizing a 1MHz Ţ xed-frequency current mode architecture. The device 1 200 200 is designed to operate in a Ţ xed-frequency PWM mode 1.1 200 240 across the full load range and can enter Power Save Mode 1.2 200 280 (PSAVE), utilizing Pulse Frequency Modulation (PFM) at light loads to maximize efŢ ciency. 1.3 200 320 1.5 178 357 Operation 1.6 200 442 During normal operation, the PMOS MOSFET is activated on each rising edge of the internal oscillator. Current 1.7 178 432 feedback for the switching regulator uses the PMOS 1.8 178 464 current path, and it is ampliŢ ed and summed with 1.875 178 487 the internal slope compensation network. The voltage feedback loop uses an external feedback divider. The on- 2.5 200 806 time is determined by comparing the summed current 2.8 178 820 feedback and the output of the error ampliŢ er. The period is set by the onboard oscillator or by an external clock 3 178 887 attached to the SYNC/PWM pin. 3.3 100 560 3.6 100 620 The SC196 has an internal synchronous NMOS rectiŢ er and does not require a Schottky diode on the LX pin. 3.8 100 665 Output Voltage Selection Continuous Conduction & Oscillator Synchronization The output voltage can be programmed using a resistor The SC196 is designed to operate in continuous network connected from VOUT to ADJ to GND. The conduction, Ţ xed-frequency mode. When the SYNC/PWM combined resistance of the divider chain should be pin is tied high the part runs in PWM mode using the greater than 10KΩ and less than 1MΩ. Table 1 lists internal oscillator. The part can be synchronized to an appropriate resistors which limit the bias current required external clock by driving a clock signal into the SYNC/ of the external feedback resistor chain and ensuring good PWM pin. The part synchronizes to the rising edge of the noise immunity. clock. The output voltage can be adjusted between less than Protection Features 0.8V and V . The output voltage formula is: IN The SC196 provides the following protection features: § · R FB1 V 0.5u¨ 1¸ OUT ¨ ¸ R • Thermal Shutdown © FB2 ¹ • Current Limit V = output voltage (V) OUT • Over-Voltage Protection R = feedback resistor from VOUT to ADJ (Ω) FB1 • Soft-Start R = feedback resistor from ADJ to GND (Ω) FB2 Thermal Shutdown Resistors with 1% or better tolerance are recommended The device has a thermal shutdown feature to protect the to ensure voltage accuracy. SC196 if the junction temperature exceeds 145°C. In thermal shutdown, the on-chip power devices are disabled, effectively tri-stating the LX output. Switching will resume when the temperature drops by 10°C. During this time, © 2007 Semtech Corp. www.semtech.com 7 SC196 POWER MANAGEMENT PRELIMINARY Applications Information (Cont.) the output capacitor. The burst-to-off period in PSAVE will if the output voltage decreases by more than 60% of its programmed value, a soft-start will be invoked. decrease as the load current reduces. Current Limit The PSAVE switching burst frequency is controlled so that The PMOS and NMOS power devices of the buck switcher the inductor current ripple is similar to that in PWM mode. The minimum switching frequency during this period is stage are protected by current limit functions. In the case of a short to ground on the output, the part enters limited to 650kHz. frequency foldback mode, which causes the switching frequency to divide by a factor determined by the output The SC196 automatically detects when to exit PSAVE voltage. This prevents the inductor current from "stair- mode by monitoring V . For the SC196 to exit PSAVE OUT mode, the load must be increased, causing V to casing". OUT decrease until the power save exit threshold is reached. Over-Voltage Protection PSAVE levels are set high to minimize the undershoot Over-voltage protection is provided on the SC196. In the when exiting PSAVE. The lower PSAVE comparator level event of an over-voltage on the output, the PWM drive is is set +0.7% above V , and the upper comparator level OUT at +1.5% above V , with the exit threshold at -2% below disabled, effectively tri-stating the LX output. The part will OUT not resume switching until the output voltage has fallen V . OUT 2% below the regulation voltage. If PSAVE operation is required, then a 22μF output Soft-Start capacitor must be used. The soft-start mode is enabled after every shutdown Higher Load cycle to limit in-rush current. In conjunction with the Applied BURST OFF frequency foldback, this controls the maximum current 1.5% during start-up. The PMOS current limit is stepped up through seven soft-start levels to the full value by a timer 0.7% PSAVE Mode at Light Load PWM Mode at Medium/ driven from the internal oscillator. During soft-start, the High Load VOUT switching frequency is stepped through 1/8, 1/4, 1/2 -2% and full internal oscillator frequency. The time at which these steps are made is controlled by the output voltage reaching predeŢ ned threshold levels. When the output Inductor Current voltage is within 2% of the regulation voltage, soft-start mode is disabled. Power Save Mode Operation 0 A The PSAVE mode may be selected by tying the SYNC/PWM Time pin to GND. Selecting PSAVE mode will enable the SC196 Figure 1 — Power Save Operation to automatically activate/deactivate operation at light loads, maximizing efŢ ciency across the full load range. The SC196 automatically detects the load current at which 100% Duty Cycle Operation it should enter PSAVE mode. The SC196 is optimized to The 100% duty cycle mode may be selected by connecting track maximum efŢ ciency with respect to V . the MODE pin high. This will allow the SC196 to maintain IN output regulation under conditions of low input voltage/ In PSAVE mode, V is driven from a lower level to an high output voltage conditions. OUT upper level by a switching burst. Once the upper level has been reached, the switching is stopped and the quiescent In 100% duty cycle operation, as the input supply drops current is reduced. V falls from the upper to lower levels toward the output voltage, the PMOS on-time increases OUT in this low current state as the load current discharges linearly above the maximum value in Ţ xed-frequency operation until the PMOS is active continuously. Once © 2007 Semtech Corp. www.semtech.com 8 SC196 POWER MANAGEMENT PRELIMINARY Applications Information (Cont.) the PMOS is switched on continuously, the output voltage Table 1 — Recommended Inductors tracks the input voltage minus the voltage drop across the PMOS power device and inductor according to the Rated Dimensions Value DCR Tolerance following relationship: Manufacturer/Part # Current LxWxH (μH) (Ω) (%) (A) (mm) V = V - I x (R + R ) BI Technologies OUT IN OUT DSP IND 4.1 0.057 1.95 20 5.7 × 5.7 ×2.0 HM66404R1 Coilcraft where 4.7 0.09 1.5 20 6.6 × 4.5 × 3.0 D01608C-472ML V = Output voltage OUT TDK 4.7 0.098 1.24 30 4.0 × 4.0 × 2.0 V = Input voltage VLCF4020T- 4R7N1R2 IN I = Output current OUT Taiyo Yuden 4.7 0.050 1.2 30 5.0 × 5.0 × 2.0 LMNP04SB4R7N R = PMOS switch ON resistance DSP R = Series resistance of the inductor TOKO IND 4.7 0.087 1.14 20 5.0 × 5.0 × 2.0 D52LC Sumida 4.7 0.050 1.2 30 3.8 × 3.8 × 1.8 Inductor Selection CDRH3D16 The SC196 is designed for use with a 4.7μH inductor. Where Coilcraft 4.7 0.2 1.1 20 3.0 × 3.0 × 1.5 LPS3015 V > 3.8V is required, a 10μH inductor is recommended. OUT The magnitude of the inductor current ripple depends on Note: recommended Inductors do not necessarily guarantee rated perfor- the inductor value and can be determined by the following mance of the part. equation: § · V V C Selection OUT OUT OUT 'I ¨1 ¸ L ¨ ¸ The internal compensation is designed to work with a Lu f V osc © IN ¹ certain output Ţ lter corner frequency deŢ ned by the equation: This equation demonstrates the relationship between input voltage, output voltage, and inductor ripple current. 1 f C 2S Lu C OUT The inductor should have a low DCR to minimize the conduction losses and maximize efŢ ciency. As a minimum This Ţ lter has a single pole and is designed to operate with requirement, the DC current rating of the inductor a minimum output capacitor value of 10μF. Larger output should be equal to the maximum load current plus half capacitor values will improve transient performance. of the inductor current ripple as shown by the following If PSAVE operation is required, the minimum capacitor equation: value is 22μF. 'I L I IOUT(MAX) L(PK) 2 Output voltage ripple is a combination of the voltage ripple from the inductor current charging and discharging Final inductor selection will depend on various design con- the output capacitor and the voltage created from the siderations such as efŢ ciency, EMI, size and cost. Table 2 inductor current ripple through the output capacitor ESR. lists the manufacturers of practical inductor options. Selecting an output capacitor with a low ESR will reduce the output voltage ripple component, as can be seen in C Selection IN the following equation: The source input current to a buck converter is non- continuous. To prevent large input voltage ripple, a low ΔV = ΔI x ESR OUT(ESR) L(RIPPLE) COUNT ESR ceramic capacitor is required. A minimum value of 10μF should be used for input voltage Ţ ltering, while a Capacitors with X7R or X5R ceramic dielectric are strongly 22μF capacitor is recommended for improved input recommended for their low ESR and superior temperature voltage Ţ ltering. © 2007 Semtech Corp. www.semtech.com 9 SC196 POWER MANAGEMENT PRELIMINARY Applications Information (Cont.) and voltage characteristics. Y5V capacitors should not be used as their temperature coefŢ cients make them unsuitable for this application. Attention should be paid to the DC voltage characteristics of the ceramic capacitors to be used for both input and output. Parts with different case sizes can vary signiŢ cantly. For example a 22μF X5R 0805 capacitor with 3.6V DC applied could have a capacitance as low as 12μF. When a 1206 size part is used, the capacitance is approximately 20μF. Table 3 lists the manufacturers of recommended capacitor options. Table 3 — Recommended Capacitors Rated Value Temperature Manufacturer/Part # Voltage Case Size (μF) Characteristic (VDC) Murata 22 6.3 X5R 0805 GRM21BR60J226ME39L Murata GRM422X5R226 22 16 X5R 1210 K16H533 Murata GRM188R60J106 10 6.3 X5R 0603 MKE19 TDK 10 6.3 X5R 0603 C2012X5R0J106K Note: Where PSAVE operation is required, 22μF must be used for C . OUT Feed-Forward Compensation Capacitor A small 10pf compensation capacitor, C is required FB1 to ensure correct operation. This capacitor should be connected directly across feedback resistor R . FB1 Capacitors with X7R or X5R ceramic dielectric are strongly recommended for their superior temperature characteristics. © 2007 Semtech Corp. www.semtech.com 10 SC196 POWER MANAGEMENT PRELIMINARY Applications Information (Cont.) 2. Route the output voltage feedback path away from the PCB Layout Considerations inductor and LX node to minimize noise and magnetic Poor layout can degrade the performance of the DC-DC interference. Keep R and R close to the ADJ pin converter and can contribute to EMI problems, ground FB1 FB2 to avoid noise pickup. bounce and resistive voltage losses. Poor regulation and 3. Maximize ground metal on the component side to instability can result. improve the return connection and thermal dissipation. Separation between the LX node and GND should be A few simple design rules can be implemented to ensure maintained to avoid coupling of switching noise to the good layout: ground plane. 4. Use a ground plane with several vias connecting to 1. Place the inductor and Ţ lter capacitors as close to the the component side ground to further reduce noise device as possible and use short wide traces between interference on sensitive circuit nodes. the power components. GND L OUT C IN V IN LX V OUT C OUT GND SYNC/PWM SC196 EN MODE C FB1 R R FB2 FB1 GND © 2007 Semtech Corp. www.semtech.com 11 SC196 POWER MANAGEMENT PRELIMINARY Typical Characteristics EfŢ ciency vs. Load Current V = 2.5V EfŢ ciency vs. Load Current V = 3.3V OUT OUT R +R =10KΩ R +R =10KΩ FB1 FB2 FB1 FB2 100 100 VIN=3.3V PSAVE V =3.9V PSAVE 90 IN 90 80 80 70 70 V =3.3V PWM VIN=3.2V PWM IN 60 60 V =4.2V PWM V =4.2V PWM IN IN 50 V =4.2V PSAVE IN 50 V =4.2V PSAVE IN V =5.0V PWM IN V =5.0V PWM IN V =5.0V PSAVE IN 40 40 V =5.0V PSAVE IN 30 30 20 20 10 10 0 0 0.0001 0.001 0.01 0.1 1 10 0.0001 0.001 0.01 0.1 1 10 I (A) I (A) OUT OUT EfŢ ciency vs. Load Current V = 1.0V EfŢ ciency vs. Load Current V = 1.8V OUT OUT R +R =10KΩ R +R =10KΩ FB1 FB2 FB1 FB2 100 100 V =2.7V PSAVE IN 90 V =2.7V PSAVE 90 IN 80 80 70 70 V =2.7V PWM IN 60 60 VIN=3.6V PWM V =3.6V PSAVE IN V =3.6V PSAVE IN 50 50 V =2.7V PWM V =4.2V PSAVE IN V =4.2V PWM IN V =4.2V PSAVE IN IN 40 40 V =3.6V PWM IN 30 30 V =4.2V PWM IN 20 20 10 10 0 0 0.001 0.0001 0.001 0.01 0.1 1 10 0.0001 0.01 0.1 1 10 I (A) I (A) OUT OUT PWM to PSAVE Hysteresis EfŢ ciency vs. Input Voltage I =750mA (PWM) / 50mA (PSAVE), R +R =10KΩ OUT FB1 FB2 V =3.6V, V =1.8V IN OUT 100 1.82 V =3.3V PWM 95 OUT 1.815 90 V =3.3V PSAVE OUT 85 1.81 V =1.0V PWM OUT 80 PSAVE Exit 1.805 PSAVE Entry 75 V =1.0V PSAVE OUT IOUT Increasing I Decreasing OUT 70 1.8 65 1.795 60 0 0.1 0.2 0.3 0.4 0.5 0.6 2.4 2.8 3.2 3.6 4.0 4.4 4.8 5.2 5.6 IOUT(A) V (V) IN © 2007 Semtech Corp. www.semtech.com 12 Efficiency (%) Efficiency (%) Efficiency (%) V (V) OUT Efficiency (%) Efficiency (%) SC196 POWER MANAGEMENT PRELIMINARY Typical Characteristics (Cont.) V vs. V Load Regulation OUT IN V =3.6V, V =1.8V IN OUT V =1.8V, I =750mA(PWM)/50mA(PSAVE) OUT OUT 1.82 1.82 PSAVE 1.815 1.81 PSAVE 1.81 1.8 PWM 1.805 1.79 1.8 PWM 1.78 1.795 1.77 1.79 1.76 1.785 2.4 2.8 3.2 3.6 4 4.4 4.8 5.2 5.6 6 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 V (V) IN I (A) OUT V vs. Temperature V =1.8V Current Limit OUT OUT V =3.6V, V =1.8V, PWM IN OUT V =3.6V, V =1.8V, I =100mA IN OUT OUT 2 1.798 1.8 1.796 1.6 1.794 PSAVE 1.4 1.792 1.2 1.79 1 1.788 0.8 1.786 0.6 1.784 PWM 0.4 1.782 0.2 1.78 0 1.778 -60 -40 -20 0 20 40 60 80 100 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 2.2 2.4 T (°C) I (A) A OUT Quiescent Current vs. Input Voltage, PSAVE Mode Quiescent Current vs. Input Voltage, PWM Mode PSAVE Mode PWM Mode 22 6 21 T -40°C T 85°C A= A= T 85°C A= 5.5 20 T 25°C A= 19 5 18 TA=25°C 17 4.5 16 4 15 T -40°C A= 14 3.5 13 12 3 2.5 3 3.5 4 4.5 5 5.5 6 2.53 3.54 4.55 5.56 V (V) V (V) IN IN © 2007 Semtech Corp. www.semtech.com 13 V (V) OUT V (V) OUT Quiescent current (μA) V (V) OUT Quiescent current (mA) V (V) OUT SC196 POWER MANAGEMENT PRELIMINARY Typical Characteristics (Cont.) P-Channel R vs. Input Voltage N-Channel R vs. Input Voltage DSON DSON 0.40 0.22 0.35 0.20 T =85°C A T =85°C A 0.18 0.30 T =25°C A T =25°C A 0.25 0.16 T =-40°C A T =-40°C A 0.14 0.20 0.15 0.12 0.10 0.10 2.7 3.2 3.7 4.2 4.7 5.2 2.7 3.2 3.7 4.2 4.7 5.2 V (V) V (V) IN IN Switching Frequency vs. Temperature 100% Duty Cycle Mode V =3.4V, V =3.3V, I =150mA, PWM 1050 IN OUT OUT V =5.5V IN 1040 V =3.6V IN 1030 V (20mV/div) OUT 1020 I (200mA/div) LX 1010 V =2.7V IN 1000 990 V (2V/div) LX 980 970 960 950 Time (2μs/div) -50 -30 -10 10 30 50 70 90 110 130 T (°C) J PSAVE Operation PWM Operation V =3.6V, V =1.8V, I =150mA, PSAVE V =3.6V, V =1.8V, I =150mA, PWM IN OUT OUT IN OUT OUT V (20mV/div) V (50mV/div) OUT OUT I (500mA/div) I (500mA/div) LX LX V (5V/div) V (2V/div) LX LX Time (1μs/div) Time (2μs/div) © 2007 Semtech Corp. www.semtech.com 14 R (Ω) DSON Switching Frequency (kHz) R (Ω) DSON SC196 POWER MANAGEMENT PRELIMINARY Typical Characteristics (Cont.) PSAVE Start-up PWM Start-up V =3.6V, V =1.8V, I =1.5A, PWM V =3.6V, V =1.8V, I =10mA, PSAVE IN OUT OUT IN OUT OUT V (5V/div) EN V (5V/div) EN V (1V/div) OUT V (1V/div) OUT I (500mA/div) IN I (100mA/div) IN Time (100μs/div) Time (1ms/div) Load Transient Response-1 Load Transient Response-2 V =3.6V, V =1.8V, I =100mA to 1.5A, PWM V =3.6V, V =1.8V, I =10mA to 1.5A, PWM IN OUT OUT IN OUT OUT V (200mV/div) OUT V (200mV/div) OUT I (500mA/div) OUT I (500mA/div) OUT Time (400μs/div) Time (400μs/div) Load Transient Response-3 Load Transient Response-4 V =3.6V, V =1.8V, I =100mA to 1.5A, PSAVE V =3.6V, V =1.8V, I =10mA to 1.5A, PSAVE IN OUT OUT IN OUT OUT V (200mV/div) V (200mV/div) OUT OUT I (500mA/div) I (500mA/div) OUT OUT Time (400μs/div) Time (400μs/div) © 2007 Semtech Corp. www.semtech.com 15 SC196 POWER MANAGEMENT PRELIMINARY Applications Circuits V Programmed to 1.2V, no PSAVE OUT V OUT L1 V IN 1.2V 4.7μH 2.5V to 5.5V 1.5A SC196 VIN LX R FB1 C FB1 VOUT 280k C PVIN IN 10pF 0.1% 10μF C OUT ADJ MODE 10μF R FB2 EN 200k 0.1% SYNC/PWM PGND GND The output voltage is set at 1.2V by the selection of the two resistors R and R , using resistor values from FB1 FB2 Table 1. PWM-only mode operation is selected by connecting the SYNC/PWM pin to the VIN pin. The 100% duty cycle capability is selected by connecting the MODE pin to the VIN pin. A 10μF capacitor is selected for the output, as PSAVE operation is not required in this application. © 2007 Semtech Corp. www.semtech.com 16 SC196 POWER MANAGEMENT PRELIMINARY Outline Drawing — MLPD-UT10 3x3x0.6 DIMENSIONS A E B INCHES MILLIMETERS DIM MIN NOM MAX MIN NOM MAX - - A .018 .024 0.45 .60 - - A1 .000 .002 0.00 0.05 A2 (.006) (0.1524) b .007 .009 .011 0.18 0.23 0.30 E C .074 .079 .083 1.87 2.02 2.12 D .042 .048 .052 1.06 1.21 1.31 PIN 1 E .114 .118 .122 2.90 3.00 3.10 INDICATOR e .020 BSC 0.50 BSC (LASER MARK) L .012 .016 .020 0.30 0.40 0.50 N 10 10 aaa .003 0.08 bbb .004 0.10 A SEATING PLANE aaa C A1 C A2 C 1 2 LxN D N e bxN bbb C A B NOTES: 1. CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES). 2. COPLANARITY APPLIES TO THE EXPOSED PAD AS WELL AS TERMINALS. © 2007 Semtech Corp. www.semtech.com 17 SC196 POWER MANAGEMENT PRELIMINARY Land Pattern — MLPD-UT10 3x3x0.6 K DIMENSIONS DIM INCHES MILLIMETERS (.112) (2.85) C G .075 1.90 H .055 1.40 H G (C) Z K .087 2.20 P .020 0.50 X .012 0.30 Y Y .037 0.95 X Z .150 3.80 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. THERMAL VIAS IN THE LAND PATTERN OF THE EXPOSED PAD SHALL BE CONNECTED TO A SYSTEM GROUND PLANE. FAILURE TO DO SO MAY COMPROMISE THE THERMAL AND/OR FUNCTIONAL PERFORMANCE OF THE DEVICE Contact Information Semtech Corporation Power Management Products Division 200 Flynn Road, Camarillo, CA 93012 Phone: (805) 498-2111 FAX (805) 498-3804 www.semtech.com © 2007 Semtech Corp. www.semtech.com 18