AMC3100 1.5MHz, 600mA SYNCHRONOUS STEP-DOWN CONVERTER www.addmtek.com DESCRIPTION FEATURES The AMC3100 is a high efficiency synchronous buck DC/DC converter using a constant frequency, current mode architecture. Adjustable version and fixed output voltages of 1.2V, 1.5V and 1.8V are available. 300uA low supply current at no load and <1µA supply current at shutdown. The 2.5V to 5.5V input voltage range makes the AMC3100 ideally suited for single Li-Ion battery-powered applications. 100% duty cycle provides low dropout operation, extending battery life in portable systems. PWM pulse skipping mode operation provides very low output ripple voltage for noise sensitive applications. Switching frequency is internally set at 1.5MHz, allowing using small surface mount inductors and capacitors. The internal synchronous switch increases efficiency and eliminates the need for an external Schottky diode. Low output voltages are easily supported with the 0.6V feedback reference voltage. The AMC3100 is available in a low profile (1mm) Thin SOT-23-5L package. RUN 4.7uF VOUT GND High Efficiency: Up to 96% 600mA Output Current at VIN=3V 2.5V to 5.5V Input Voltage Range 1.5MHz Constant Switching Frequency No Schottky Diode Required 100% Duty Cycle as Low Dropout Operation 0.6V Reference Voltage Allows 0.6V Minimum Output Voltage <1µA Shutdown Mode Supply Current Current Mode Operation for Excellent Line and Load Transient Response Over-temperature Protected 4KV HBM ESD Protection 5-Pin Thin SOT-23 package APPLICATIONS AMC3100-1.8 CIN L SW VOUT＝1.8V / 600mA VIN TYPICAL APPLICATION VIN＝2.5V to 5.5V PDA, Personal Media Player Smart Phone Digital Still Camera, Video Camcorder Portable Instruments Bluetooth Headset PACKAGE PIN OUT COUT 10uF GND 2 SW SYMBOLIZATION Device Name Output Voltage AMC3100DBFT AMC3100-1.2DBFT AMC3100-1.5DBFT AMC3100-1.8DBFT DB Note: Adjustable 1.2V Fixed 1.5V Fixed 1.8V Fixed Marking 3 A64X RUN 1 5 VFB / VOUT* 4 VIN TSOT-23-5L ( Top View ) A64A A642 A645 A648 * Note: VFB pin for adjustable version. VOUT pin for fixed voltage version. ORDER INFORMATION SOT-23 5-pin AMC3100DBF (Adjustable) AMC3100-X.XDBF (Fixed Voltage) 1. All surface-mount packages are available in Tape & Reel. Append the letter “T” to part number (i.e. AMC3100-1.8DBFT). 2. The letter ”F” is marked for Lead Free process. Copyright © 2006 ADDtek Corp. 1 DD010_A -- JUNE 2006 AMC3100 PIN DESCRIPTION Pin Number Pin Name 1 RUN Enable pin. Higher than 1.5V to turn on the device. Lower than 0.3V to turn it off. The shutdown mode supply current less than <1µA supply current. This pin should not be floating. 2 GND Ground 3 SW Power Switch Output. Connects to the drains of the internal P-CH and N-CH MOSFET switches. 4 VIN Supply Input Pin. 5 VFB/VOUT Pin Function VFB (AMC3100): Feedback Input Pin. Connect VFB to the center point of the external resistor divider. The feedback threshold voltage is 0.6V. VOUT (AMC3100-X.X): Output Voltage Feedback Pin. An internal resistive divider divides the output voltage down for comparison to the internal reference voltage. PACKAGE THERMAL DATA Thermal Resistance from Junction to Ambient, θJA 250 OC /W Note : Junction Temperature Calculation: TJ = TA + (PD x θJA). PD: Power Dissipation, TA: Ambient temperature, θJA: Thermal Resistance-Junction to Ambient The θJA numbers are guidelines for the thermal performance of the device/PC-board system. All of the above assume no ambient airflow. Copyright © 2006 ADDtek Corp. 2 DD010_A -- JUNE 2006 AMC3100 BLOCK DIAGRAM SLOPE C OM P OSC _ FR EQ SH IFT V F B /V O UT 5 R1 0.65V OSC _ + 0.6V FB 0.4V + EA SLEEP + BR UST － S R2 Q R Q RS LATC H SW IT CH IN G LOG IC AN D BLANK IN G C IR C UIT _ + ICO M P 4 VIN 3 SW 2 GN D 5Ω ANT ISH OOTT H RU Bandgap R eference R UN + IRCM P 1 _ ABSOLUTE MAXIMUM RATINGS (Note 1) -0.3V to 6V -0.3V to VIN -0.3 to VIN+0.3V 800mA 800mA 1.3A -40OC to 85OC 125OC -60OC to 150OC 300OC Input Voltage, VIN RUN, VFB Voltage SW Voltage P-Channel Switch Source Current (DC) N-Channel Switch Sink Current (DC) Peak SW Sink and Source Current Operating Temperature Range (Note 2) Junction Temperature, TJ (Note 3) Storage Temperature Range Lead Temperature (soldering, 10 seconds) Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note 2: The AMC3100 is guaranteed to meet performance specifications from 0°C to 70°C. Specifications over the –40°C to 85°C operating temperature range are assured by design, characterization and correlation with statistical process controls. Note 3: TJ is calculated from the ambient temperature TA and power dissipation PD according to the following formula: TJ = TA + (PD x θJA). Copyright © 2006 ADDtek Corp. 3 DD010_A -- JUNE 2006 AMC3100 RECOMMENDED OPERATING CONDITIONS Parameter Symbol Min Supply Voltage VIN Operating free-air temperature range TA Typ Max Unit 2.5 5.5 V -40 85 ℃ ELECTRICAL CHARACTERISTICS VIN=3.6V, TA=25°C. (Unless otherwise noted) Parameter Symbol Input DC Supply Current Active Mode IS Shutdown Regulated Output Voltage VOUT Output Voltage Line Regulation △VOUT Output Voltage Load Regulation VLDREG Peak Inductor Current IPK Feedback Current IVFB Regulated Feedback Voltage Reference Voltage Line Regulation VFB △VFB Condition Typ Max VFB=0.5V or VOUT=90%, ILOAD=0A 300 400 VRUN=0V, VIN=4.2V 0.1 1 1.800 1.500 1.200 1.854 1.545 1.236 0.04 0.4 AMC3100-1.8, IOUT=100mA AMC3100-1.5, IOUT=100mA AMC3100-1.2, IOUT=100mA Min µA 1.746 1.455 1.164 VIN=2.5V to 5.5V 0.5 Duty Cycle < 35%, VIN=3V, VFB=0.5V or VOUT=90%, TA= 25°C TA= 0°C ≤ TA ≤ 85°C TA= -40°C ≤ TA ≤ 85°C Unit 0.75 0.5880 0.5865 0.5850 VIN=2.5V to 5.5V %V % 1.25 A ±30 nA 0.6 0.6 0.6 0.6120 0.6135 0.6150 V 0.04 0.4 %V 1.5 1.8 MHz Oscillator Frequency fOSC VFB=0.6V or VOUT=100% RDS(ON) of P-Channel FET RPFET ISW=100mA 0.4 0.5 Ω RDS(ON) of N-Channel FET RNFET ISW=-100mA 0.35 0.45 Ω SW Leakage ILSW VRUN=0V, VSW=0V or 5V, VIN=5V ±0.01 ±1 µA RUN Threshold VRUN 1 1.5 V RUN Leakage Current IRUN ±0.01 ±1 µA Copyright © 2006 ADDtek Corp. 1.2 1 V 0.3 4 DD010_A -- JUNE 2006 AMC3100 CHARACTERIZATION CURVES Efficiency vs Output Current 100 100 VIN=2.7V 90 80 70 VIN=5.5V 50 VIN=5.5V 60 VIN=4.2V 50 VIN=4.2V 40 40 30 30 VOUT =1.5V TA=25°C 20 10 10 10 Output Current ( mA ) 30 10 Output Current ( mA ) 0.1 1000 1.8 I LOAD=100mA 80 75 I LOAD=10mA 70 I LOAD=300mA 65 I LOAD=600mA 60 VOUT =2.5V TA=25°C 55 50 2 3 4 5 1.6 1.5 1.4 1.3 I LOAD=200mA 1.2 I LOAD=100mA 1.1 -50 -25 Load Regulation 1.4 1.3 I LOAD=200 mA 25 2 50 75 100 125 150 3 4 5 6 Supply Voltage ( V ) RDS (ON) vs Tem perature 0.6 ILOAD=100 mA 0.5 R DS(ON) ( Ω ) 1.51 0 0.6 VIN=3.6V VOUT =1.5V TA=25°C 1.52 I LOAD=100 mA 1.5 RDS (ON) vs Input Voltage 1.55 1.53 1.6 Temperature ( °C ) Input Voltage ( V ) 1.54 VOUT =1.5V TA=25°C 1.7 1.2 1 6 0.5 TA=25°C 0.4 R DS(ON) ( Ω ) 85 1000 Oscillator Frequency vs Supply Voltage VIN=3.6V VOUT =1.5V 1.7 10 Output Current ( mA ) Oscillator Frequency (MHz) Oscillator Frequency (MHz) 90 VOUT =2.5V TA=25°C 10 1.8 I LOAD=250mA 95 Efficiency ( % ) 40 Oscillator Frequency vs Tem perature Efficiency vs Input Voltage 100 VIN=3.6V 50 0 0.1 1000 VIN=5.5V 60 0 0.1 Output Voltage ( V ) 70 20 VOUT =1.8V TA=25°C 20 0 VIN=4.2V 80 70 VIN=3.6V 60 VIN=2.7V 90 VIN=3.6V Efficiency ( % ) Efficiency ( % ) VIN=2.7V 90 80 Efficiency vs Output Current 100 Efficiency ( % ) Efficiency vs Output Current Main switch 0.3 0.2 0.1 0.4 VIN=3.6V Main switch VIN=4.2V Synchronous VIN=2.7V 0.3 0.2 switch 0.1 Synchronous switch 1.5 0 0 100 200 300 400 500 600 700 800 Output Current ( mA ) Copyright © 2006 ADDtek Corp. 0 2 3 4 5 Input Voltage ( V ) 5 6 7 -50 -25 0 25 50 75 100 125 150 Temperature ( °C ) DD010_A -- JUNE 2006 AMC3100 Dynam ic Supply Current vs Tem perature Dynam ic Supply Current vs Supply Voltage 380 340 320 300 280 260 240 220 10 360 VIN=3.6V VOUT =1.5V I LOAD=0mA 340 320 Switch Leakage Current (uA) VOUT =1.5V I LOAD=0mA TA=25°C 360 Dynamic Supply Current ( uA ) Dynamic Supply Current( uA ) 380 Sw itch Leakage vs Tem perature 300 280 260 240 220 200 200 2 3 4 5 -50 -25 6 0 25 50 VRUN=0V VIN=5V 8 6 v SW =5V 4 v SW =0V 2 0 75 100 125 150 -50 -25 Transient vs Output Current Line Regulation 1.5 1.4 30 25 20 15 10 1.3 5 1.2 0 0 1 2 3 4 5 Input Voltage ( V ) 0.66 0.64 0.62 0.6 0.58 0.56 0.54 0.52 0.5 0 6 VIN=3.6V I LOAD=100mA 0.68 VOUT =1.5V TA=25°C Reference Voltage( V ) Transient Voltage ( mV ) Output Voltage ( V ) 1.6 100 200 300 400 500 600 700 800 -50 -25 Output Current ( mA ) Discontinuous Operation 75 100 125 150 0.7 35 VOUT =1.5V TA=25°C 50 Reference Voltage vs Tem perature 40 1.8 25 Temperature ( °C ) Temperature ( °C ) Supply Voltage ( V ) 1.7 0 0 25 50 75 100 125 150 Temperature (°C ) Load Step Start-up from Shutdown VOUT SW 2V/DIV VOUT 10mV/DIV RUN 5V/DIV 100mV/DIV VOUT 1V/DIV IL 500mA/DIV AC Coupled IL 200mA/DIV ILOAD IL 500mA/DIV 500mA/DIV 40us/DIV VIN =3.6V 20us/DIV VOUT =1.5V ILOAD=0mA to 600mA Copyright © 2006 ADDtek Corp. 6 DD010_A -- JUNE 2006 AMC3100 Load Step Load Step Load Step VOUT VOUT VOUT 100mV/DIV 100mV/DIV 100mV/DIV IL IL IL 500mA/DIV 500mA/DIV 500mA/DIV ILOAD ILOAD ILOAD 500mA/DIV 500mA/DIV 500mA/DIV VIN =3.6V 20us/DIV VOUT =1.5V ILOAD=50mA to 600mA Copyright © 2006 ADDtek Corp. VIN =3.6V 20us/DIV VOUT =1.5V ILOAD=100mA to 600mA VIN =3.6V 20us/DIV VOUT =1.5V ILOAD=200mA to 600mA 7 DD010_A -- JUNE 2006 AMC3100 APPLICATION INFORMATION The basic AMC3100 application circuit is shown in Figure 1. External component selection is driven by load requirement: Adjustable Output Voltage: In adjustable version, the output voltage is set by the below formula (1): R1 ⎞ ⎛ V OUT = 0 .6V ⎜ 1 + ⎟ R 2⎠ ⎝ 0.6V≦VOUT≦5.5V (1) The external resistor divider sets the output voltage (see figure 1). Choose R1 around 1MΩ, R2 is then given by: R1 R2 = ⎛ V OUT ⎞ − 1⎟ ⎜ ⎝ 0 . 6V ⎠ VOUT＝2.5V Table 1- Resistor Selection vs. Adjust Output Voltage. L1 VIN＝2.5V to 5.5V Rectified R1 2.2uH 1MΩ VIN SW CIN RUN 22pF FB AMC3100-ADJ 4.7uF C1 GND R2 316KΩ COUT 10uF VOUT R1 1.2V 1MΩ, 1% 1MΩ, 1% R2 1.5V 1MΩ, 1% 667KΩ, 1% 1.8V 1MΩ, 1% 500KΩ, 1% 2.5V 1MΩ, 1% 316KΩ, 1% 3.3V 1MΩ, 1% 222KΩ, 1% Figure 1 Inductor selection: For most applications, the value of the inductor will fall in the range of 1uH to 4.7uH. Its value is chosen based on the desired ripple current. Large value inductors lower ripple current, and small value inductors result in higher ripple currents. Higher VIN or VOUT also increases the ripple current as shown in the formula (2): ∆I L = VOUT fL ⎛ VOUT ⎜⎜1 − VIN ⎝ ⎞ ⎟⎟ ⎠ Where, f = operating frequency, andΔIL = ripple current in the inductor. (2) COUT selection: The output capacitor keeps output voltage ripple small and ensures regulation loop stable. The output capacitor impedance shall be low in switching frequency. The output rippleΔVOUT approximately: ⎛ 1 ∆VOUT ≅ ∆I L ⎜⎜ ESR + 8 fCOUT ⎝ ⎞ ⎟⎟ ⎠ Copyright © 2006 ADDtek Corp. Where, COUT = output capacitance. 8 DD010_A -- JUNE 2006 AMC3100 PACKAGE ‧ TSOT-23-5L Note: All dimensions in mm. Copyright © 2006 ADDtek Corp. 9 DD010_A -- JUNE 2006 AMC3100 IMPORTANT NOTICE ADDtek reserves the right to make changes to its products or to discontinue any integrated circuit product or service without notice, and advises its customers to obtain the latest version of relevant information to verify, before placing orders, that the information being relied on is current. A few applications using integrated circuit products may involve potential risks of death, personal injury, or severe property or environmental damage. ADDtek integrated circuit products are not designed, intended, authorized, or warranted to be suitable for use in life-support applications, devices or systems or other critical applications. Use of ADDtek products in such applications is understood to be fully at the risk of the customer. In order to minimize risks associated with the customer’s applications, the customer should provide adequate design and operating safeguards. ADDtek assumes to no liability to customer product design or application support. ADDtek warrants the performance of its products to the specifications applicable at the time of sale. ADDtek Corp. 9F, No. 20, Sec. 3, Bade Rd., Taipei, Taiwan, 105 TEL: 2-25700299 FAX: 2-25700196 Copyright © 2006 ADDtek Corp. 10 DD010_A -- JUNE 2006