PAM2301CAAB150

PAM2301 PAM | Alldatasheet

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/c110 /c110 /c110 /c110 /c110 /c110 /c110 /c110 /c110 /c110 /c110 Efficiency up to 96% Only 40μA(TYP.) Quiescent Current Output Current: Up to 800mA Internal Synchronous Rectifier 1.5MHz Switching Frequency Soft Start Under-Voltage Lockout Short Circuit Protection Thermal Shutdown 5-pin Small SOT23-5 Package Cellular Phone Portable Electronics Wireless Devices Cordless Phone Computer Peripherals Battery Powered Widgets Electronic Scales Digital Frame The PAM2301 is a step-down current-mode, DC- DC converter. At heavy load, the constant- frequency PWM control performs excellent stability and transient response. To ensure the longest battery life in portable applications, the PAM2301 provides a power-saving Pulse- Skipping Modulation (PSM) mode to reduce quiescent current under light load operation to save power. The PAM2301 supports a range of input voltages from 2.5V to 5.5V, allowing the use of a single Li+/Li-polymer cell, multiple Alkaline/NiMH cell, USB, and other standard power sources. The output voltage is adjustable from 0.6V to the input voltage, while the part number suffix PAM2301- XX indicates pre-set output voltage of 3.3V, 2.8V, employ internal power switch and synchronous rectifierfor to minimize external part count and realize high efficiency. During shutdown, the input is disconnected from the output and the shutdown current is less than 0.1 A. Other key features include under-voltage lockout to prevent deep battery discharge. The PAM2301 is available in SOT23-5 package. Pb-Free Package /c110 /c110 /c110 /c110 /c110 /c110 /c110 /c110 μ Typical Application VIN SW EN VOUT GND 4 7μH. Vo Co 10μF V C 10μF IN IN www.poweranalog.com VIN SW EN FB GND 4 7μH. Vo Co 10μF V C IN IN 10μF 20pFR1 PAM2301 800mA Step-Down DC-DC Converters Fixed Output Voltage Adjustable Output Voltage 09/2008 Rev 1.3 ,Power Analog Microelectronics Inc 10.6 1 2 O RV R /c230/c246/c61/c180 /c43/c231/c247/c232/c248

Pin Configuration& Marking Information Top View SOT23 5- B AVYW 123

54 BA: Product Code of PAM2301

V: Output Voltage Y: Year W: Week ,Power Analog Microelectronics Inc www.poweranalog.com PAM2301 800mA Step-Down DC-DC Converters Pin Number Name Function 1E N Enable control input. Force this pin voltage above 1.5V, enables the chip, and below 0.3V shuts down the device.

2 GND Ground

3 SW The drains of the internal main and synchronous power MOSFET.

4 VIN Chip main power supply pin

VOUT: Output voltage feedback pin, an internal resistive divider divides the output voltage down for comparison to the internal reference voltage. FB: Feedback voltage to internal error amplifier, the threshold voltage is 0.6V. 09/2008 Rev 1.3 VOUT/FB GND SWEN VIN EN FB +-++ +PWM COMP IAMP IRCMP SW GND SYNCHRONOUS RECTIFIER NCH() MAIN SWITCH PCH() VIN COMP VIN SHUTDOWN OSC RS LATCH 0.6VREF FREQ SHIFT EA SQ RQ SWITCHING LOGIC AND BLANKING CIRCUIT SLOPE COMP 1.5M OSC ANTI SHOOT THRU

These are stress ratings only and functional operation is not implied Exposure to absolute maximum ratings for prolonged time periods may affect device reliability All voltages are with respect to ground 0.3V to V 0.3V to V +0.3V IN IN O OO O C CC Recommended Operating Conditions Max. Supply Voltage (for Max. duration of OO Thermal Information Parameter Package Symbol Maximum Unit Thermal Resistance (Junction to Case) SOT23-5 θ JC 130 Thermal Resistance (Junction to Ambient) SOT23-5 θ JA 250 °C/W Internal Power Dissipation SOT23-5 P D 400 mW ,Power Analog Microelectronics Inc www.poweranalog.com PAM2301 800mA Step-Down DC-DC Converters 09/2008 Rev 1.3

T =25 C, V =3.6V, V =1.8V, C =10μF, C =10μF,L=4.7μH, unless otherwise noted.AI N O I NO O ,Power Analog Microelectronics Inc www.poweranalog.com PAM2301 800mA Step-Down DC-DC Converters PARAMETER SYMBOL Test Conditions MIN TYP MAX UNITS Input Voltage Range V IN 2.5 5.5 V Regulated Feedback Voltage V FB 0.588 0.6 0.612 V Reference Voltage Line Regulation ΔV FB 0.3 %/V Regulated Output Voltage Accuary V O IO = 100mA -3 +3 % Peak Inductor Current I PK VIN=3V,VFB =0 . 5 Vo r VO=90% 1.2 A Output Voltage Line Regulation LNR V IN =2 . 5 Vt o5 V ,IO=10mA 0.2 0.5 %/V Output Voltage Load Regulation LDR I O=1mA to 800mA 0.5 1.5 % Quiescent Current I Q No load 40 70 μA Shutdown Current I SD VEN =0 V 0 . 1 1 μ A VO = 100% 1.2 1.5 1.8 MHzOscillator Frequency f OSC VFB =0 Vo rV O = 0V 500 kHz PM O S F E T 0 . 3 0 . 4 5 ΩDrain-Source On-State Resistance R DS(ON) IDS=100mA N MOSFET 0.35 0.5 Ω SW Leakage Current I LSW ±0.01 1 μA High Efficiency η 96 % EN Threshold High V EH 1.5 V EN Threshold Low V EL 0.3 V EN Leakage Current I EN ±0.01 μA Over Temperature Protection OTP 150 °C OTP Hysteresis OTH 30 °C 09/2008 Rev 1.3

Efficiency Output Current (Vo=1.2V)VS Typical Performance Characteristics T =25 C, C =10 F, C =10uF,L=4.7 H, unless otherwise noted.AI N O O μμ ,Power Analog Microelectronics Inc www.poweranalog.com PAM2301 800mA Step-Down DC-DC Converters Efficiency Output CurrentVS (Vo=1.5V) Efficiency Output Current ( )VS Vo=1.8V Efficiency Output Current ( )VS Vo=2.5V Efficiency Output CurrentVS 100 1 10 100 1000 Output Current(mA) Efficiency(%) 2.5V 3.6V 4.2V 100 1 10 100 1000 Output Current(mA) Efficiency(%) 2.5V 3.6V 4.2V 100 1 10 100 1000 Output Current(mA) Efficiency(%) 3.6V 4.2V 100 1 10 100 1000 Output Current(mA) Efficiency(%) 3.6V 4.2V (Vo=2.8V) 09/2008 Rev 1.3 100 1 10 100 1000 Output Current(m A) Eifficiency(%) Vin=3.6V Vin=4.2V Vin=5.0V Eifficiency VS Output Current (Vo=3.3V) 100 1 10 100 1000 Output Current(mA) Eifficiency(%) Vin=2.7V Vin=3.6V Vin=4.2V

Efficiency Input Voltage ( )VS Vo=1.2V PAM2301 800mA Step-Down DC-DC Converters Efficiency Input Voltage ( )VS Vo=1.5V Efficiency Input Voltage ( )VS Vo=1.8V Efficiency Input Voltage ( )VS Vo=2.8V Efficiency Input Voltage ( )VS Vo=2.5V ,Power Analog Microelectronics Inc www.poweranalog.com Typical Performance Characteristics T =25 C, C =10 F, C =10uF,L=4.7 H, unless otherwise noted.AI N O O μμ 100 2.5 3 3.5 4 4.5 5 Input Voltage(V) Efficiency(%) 10mA 100mA 800mA 100 2 . 533 . 544 . 55 Input Voltage(V) Efficiency(%) 10mA 100mA 800mA 100 33 . 544 . 555 . 5 Input Voltage(V) Efficiency(%) 10mA 100mA 800mA 100 33 . 544 . 555 . 5 Input Voltage(V) Efficiency(%) 10mA 100mA 800mA 09/2008 Rev 1.3 100 Input Voltage(V) Eifficiency(%) Io=10mA Io= 100mA Io= 800mA Eifficiency VS Input Voltage (Vo=3.3V) 100 2 . 53 . 54 . 55 . 5 Input Voltage(V) Eifficiency (%) Io=10mA Io=100mA Io=800mA

800mA Step-Down DC-DC Converters ,Power Analog Microelectronics Inc www.poweranalog.com Typical Performance Characteristics T =25 C, C =10 F, C =10uF,L=4.7 H, unless otherwise noted.AI N O O μμ 09/2008 Rev 1.3 0.584 0.586 0.588 0.590 0.592 0.594 0.596 0.598 0.600 0.602 23456 Input Voltage Vfb I=100mA I=600mA I=800mA 0.590 0.595 0.600 0.605 0.610 0.615 0.620 0 50 100 150 Temperature( ℃） Reference Voltage(V) 0.58 0.584 0.588 0.592 0.596 0.6 0.604 0 200 400 600 800 Load Current Vfb Vin=2.7V Vin=3.6V Vin=4.2V Vin=3.6V Reference Voltage VS Input Voltage Reference Voltage VS Temperature Reference Voltage VS Load Current 1.175 1.180 1.185 1.190 1.195 1.200 1.205 1.210 1.215 0 200 400 600 800 Load Current(mA) Output Voltage(V) Output Voltage VS Load Current Vo=1.2V Vin=3.6V Output Voltage VS Temperature Output Voltage Output CurrentVS 1.189 1.191 1.193 1.195 1.197 1.199 1.201 1.203 1.205 10 110 210 310 410 510 610 710 810 Output Current(mA) Output Voltage(V) 2.5V 3.6V 4.2V Vo=1.2V 1.188 1.189 1.19 1.191 1.192 1.193 1.194 20 40 60 80 100 120 140 Temperature(℃） Output Voltage(V) Vo=1.2V Vin =3.6V Io=100mA

800mA Step-Down DC-DC Converters ,Power Analog Microelectronics Inc www.poweranalog.com Typical Performance Characteristics T =25 C, C =10 F, C =10 F,L=4.7 H, unless otherwise noted.AI N O O μμ μ 09/2008 Rev 1.3 0.1 0.15 0.2 0.25 0.3 0.35 0.4 23456 Input Voltage RDS(ON) 0.1 0.2 0.3 0.4 0.5 0.6 20 70 120 Temperature( ℃) Rds(on) Vin=4.2V Vin=3.6V Vin=2.7V Vin=3.6V 1.2 1.3 1.4 1.5 1.6 1.7 1.8 234567 Supply Voltage(V) Oscillator Fr equency(MHz) 1.50 1.52 1.54 1.56 1.58 20 40 60 80 100 120 140 Temperature(℃） Oscillator Frequency(MHz) R VS Input Voltagedson Rdson VS Temperature Oscillator Frequency VS Supply Voltage Oscillator Frequency VS Temperature Vin=3.6V Vin=3.6V Vin=3.6V 2 . 533 . 544 . 555 . 5 Input Voltage(V) Dynamic Supply Current(uA) Dynamic Supply Current VS Input Voltage Vo=1.2V ILoad =0A 40 60 80 100 120 140 Temperature(℃） Dynamic Supply Current(uA) Dynamic Supply Current VS Temperature Vo=1.2V Vin=3.6V ILoad =0A

800mA Step-Down DC-DC Converters Load Transient Io=0-800mA Vo=1.8V Vin=3.6V Load Transient Io=50-800mA Vo=1.8V Vin=3.6V ,Power Analog Microelectronics Inc www.poweranalog.com Typical Performance Characteristics T =25 C,C =10 F, C =10 F,L=4.7 H, unless otherwise noted.AI N O O μμ μ Load Transient Io=200-800mA Vo=1.8V Vin=3.6V Start-up from Shutdown Vo=1.8V,Vin=3.6V Voltage Output Enable Inductor Current Voltage Output Inductor Current Output Current Voltage Output Inductor Current Output Current Voltage Output Inductor Current Output Current 09/2008 Rev 1.3

,Power Analog Microelectronics Inc www.poweranalog.com

Application Information

The basic PAM2301 application circuit is shown in Page 1. External component selection is determined by the load requirement, selecting L first and then Cin and Cout. For most applications, the value of the inductor will fall in the range of 1μH to 4.7μH. 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 V or Vout also increases the ripple current as shown in equation 1. A reasonable starting point for setting ripple current is I = 320mA (40% of 800mA). (1) The DC current rating of the inductor should be at least equal to the maximum load current plus half the ripple current to prevent core saturation. Thus, a 1120mA rated inductor should be enough for most applications (800mA + 320mA). For better efficiency, choose a low DC-resistance inductor. In continuous mode, the source current of the top MOSFET is a square wave of duty cycle Vout/Vin. To prevent large voltage transients, a low ESR input capacitor sized for the maximum RMS current must be used. The maximum RMS capacitor current is given by: This formula has a maximum at VIN =2Vout, where I =Iout/2. This simple worst-case condition is commonly used for design because even significant deviations do not offer much relief. Note that the capacitor manufacturer's ripple current ratings are often based on 2000 hours of life. This makes it advisable to further derate the capacitor, or choose a capacitor rated at a higher temperature than required. Consult the manufacturer if there is any question. The selection of Cout is driven by the required effective series resistance (ESR). Typically, once the ESR requirement for Cout has been met, the RMS current rating generally far exceeds the I (P-P) requirement. The output ripple Vout is determined by: Where f = operating frequency, C =output capacitance and I = ripple current in the inductor. For a fixed output voltage, the output ripple is highest at maximum input voltage since I increases with input voltage. Higher values, lower cost ceramic capacitors are now becoming available in smaller case sizes. Their high ripple current, high voltage rating and low ESR make them ideal for switching regulator applications. Using ceramic capacitors can achieve very low output ripple and small circuit size. When choosing the input and output ceramic capacitors, choose the X5R or X7R dielectric formulations. These dielectrics have the best temperature and voltage characteristics of all the ceramics for a given value and size. The internal reference is 0.6V (Typical). The output voltage is calculated as below: The output voltage is given by Resistor selection for output voltage setting Inductor Selection C and Cout Selection Using Ceramic Input and Output Capacitors Setting the Output Voltage Table 1: IN L RMS RIPPLE OUT L L IN Δ Δ Table 1. /c40/c41 /c40 /c41 /c230/c246/c68 /c231/c247/c232/c248 OUT OUTL IN 1VI= V 1 -fL V /c40/c41 12OUT IN OUT IN RMS OMAX IN VV V C required I I V /c45/c233/c249/c235/c251/c64 OUT L OUT 1VI E S R + 8fC /c230/c246/c64 /c231/c247/c232/c248 /c86/c86 PAM2301 800mA Step-Down DC-DC Converters 09/2008 Rev 1.3 Vo R1 R2 1.2V 100k 100k 1.5V 150k 100k 1.8V 200k 100k 2.5V 380k 120k 3.3V 540k 120k 10.6 1 2 O RV R /c230/c246/c61/c180 /c43/c231/c247/c232/c248

,Power Analog Microelectronics Inc www.poweranalog.com PAM2301 800mA Step-Down DC-DC Converters 09/2008 Rev 1.3 100% Duty Cycle Operation UVLO and Soft-Start Short Circuit Protection Thermal Shutdown PCB Layout Check List As the input voltage approaches the output voltage, the converter turns the P-channel transistor continuously on. In this mode the output voltage is equal to the input voltage minus the voltage drop across the P - channel transistor: V= V – I × ( R+ R ) where R = P-channel switch ON resistance, I = Output current, R = Inductor DC resistance The reference and the circuit remain reset until the VIN crosses its UVLO threshold. The PAM2301 has an internal soft-start circuit that limits the in-rush current during start-up. This prevents possible voltage drops of the input voltage and eliminates the output voltage overshoot. The soft-start acts as a digital circuit to increase the switch current in several steps to the P-channel current limit (1500mA). The switch peak current is limited cycle-by-cycle to a typical value of 1500mA. In the event of an output voltage short circuit, the device operates with a frequency of 400kHz and minimum duty cycle, therefore the average input current is typically 200mA. When the die temperature exceeds 150°C, a reset occurs and the reset remains until the temperature decrease to 120°C, at which time the circuit can be restarted. When laying out the printed circuit board, the following checklist should be used to ensure proper operation of the PAM2301. These items are also illustrated graphically in Figure 1. Check the following in your layout: 1. The power traces, consisting of the GND trace, the SW trace and the VIN trace should be kept short, direct and wide. 2. Does the V pin connect directly to the feedback resistors? The resistive divider R1/R2 must be connected between the (+) plate of C and ground. 3. Does the (+) plate of CIN connect to VIN as closely as possible? This capacitor provides the AC current to the internal power MOSFETs. 4. Keep the switching node, SW, away from the sensitive VFB node. 5. Keep the (–) plates of C and C as close as possible. OUT IN LOAD dson L dson LOAD L FB OUT IN OUT Figure 1 :PAM2301 Suggested Layout

Ordering Information

,Power Analog Microelectronics Inc www.poweranalog.com PAM2301 800mA Step-Down DC-DC Converters Output Current Pin Configuration Package Type Number of Pins Output Voltage C: 800mA A Type 1. EN 2. GND 3. SW 4. VIN 5. VOUT/FB A: SOT-23 B: 5 330: 3.3V 280: 2.8V 250: 2.5V 180: 1.8V 150: 1.5V 120: 1.2V ADJ: Adj 09/2008 Rev 1.3 Part Number Output Voltage Marking Package Type Standard Package PAM2301CAAB330 3.3V BAKYW SOT23-5 3,000Units/Tape&Reel PAM2301CAAB280 2.8V BAHYW SOT23-5 3,000Units/Tape&Reel PAM2301CAAB250 2.5V BAGYW SOT23-5 3,000Units/Tape&Reel PAM2301CAAB180 1.8V BAEYW SOT23-5 3,000Units/Tape&Reel PAM2301CAAB150 1.5V BACYW SOT23-5 3,000Units/Tape&Reel PAM2301CAAB120 1.2V BABYW SOT23-5 3,000Units/Tape&Reel PAM2301CAABADJ ADJ BAAYW SOT-23-5 3,000Units/Tape&Reel

,Power Analog Microelectronics Inc www.poweranalog.com PAM2301 800mA Step-Down DC-DC Converters 09/2008 Rev 1.3 D E E1 A2A LR E F . 0.25 L1 (REF.) θ c( R E F . ) MillimeterREF. Min Nom Max A 1.10MAX A1 0 0.05 0.10 A2 0.70 1.00 1.295 c 0.12REF. D 2.70 2.90 3.10 E 2.60 2.80 3.00 E1 1.40 1.60 1.80 L 0.45REF. L1 0.60REF. θ 0º 5º 10º b 0.30 0.40 0.50 e 0.95REF. e1 1.90REF.