PS3120A

PS3120A PULAN | Alldatasheet

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 Fixed 4.94V±3% Output  VIN Range: 2.7V to 4.5V  Output Current: Up to 110mA (VIN≥3V) Up to 230mA (VIN≥3.6V)  Low Noise Constant Frequency (360kHz) Operation  Shutdown Current <1 μA  No Inductors  Available in Low Profile 6-Lead SOT23 Package AApppplliiccaattiioonnss  White LED Backlighting  Li-Ion Battery Backup Supplies  Smart Card Readers DDeessccrriippttiioonn The PS3120A is a low noise switched capacitor voltage doubler. It produces a regulated output voltage from a 2.7V to 4.5V input. Low external parts count (one flying capacitor and two small bypass capacitors at VIN and VOUT) make the PS3120A ideally suited for small, battery-powered applications. The PS3120A have thermal shutdown capability and can survive a continuous short circuit from VOUT to GND. A low current shutdown feature disconnects the load from VIN and reduces quiescent current to <1μA. The PS3120A is available in the industry standard SOT-23-6L power packages.  PCMCIA Local 5V Supplies PS3120A PS3120A-GV2.3 PULAN TECHNOLOGY PULAN TECHNOLOGY CO., LIMITED TTyyppiiccaall AApppplliiccaattiioonn GND VOUTVIN5 1 CIN 10µF COUT 10µF DC+ VOUT C+C- C FLY 10µF PS3120A EN3 ON OFF 2.7V ~ 4.5V 4.94V Figure 1: Regulated 4.94V Output

PPiinn AAssssiiggnnmmeenntt aanndd DDeessccrriippttiioonn 123 456 SOT-23-6L PIN NAME

DESCRIPTION

1 VOUT Output

2 GND Ground

3 EN ON/OFF Control (High Enable)

4 C- Flying Capacitor Negative Terminal.

5 VIN Input

6 C+ Flying Capacitor Positive Terminal. AAbbssoolluuttee MMaaxxiimmuumm RRaattiinnggss (Note 1)  V IN  V OUT  V EN  I OUT Note 1: Stresses listed as the above “Absolute Maximum Ratings” may cause permanent damage to the device. Exposure to absolute maximum rating conditions for extended periods may remain possibility to affect device reliability. Note 2: Based on long term current density limitations. Note 3: The PS3120A are 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 des ign, characterization and correlation with statistical process controls. PS3120A PS3120A-GV2.3 PULAN TECHNOLOGY CO., LIMITED PULAN TECHNOLOGY 深圳百盛新纪元半导体有限公司一级代理商

EElleeccttrriiccaall CChhaarraacctteerriissttiiccss Operating Conditions: TA = 25 ℃, V EN = V IN , C IN = C OUT = C FLY = 10μF, unless otherwise noted. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS V IN Input Voltage Range 2.7 4.5 V V OUT Output Voltage Range 2.7V <V IN < 5.5V, I OUT 65mA 4.8 4.94 5.1 V I SHDN Shutdown Current V EN = 0V,V OUT = 0V 0.2 μA I NO-LOAD No Load Input Current I OUT = 0mA, V IN = 3V 0.17 mA V RIPPLE Output Ripple V IN = 3.6V , I OUT = 100mA 20 mVP-P EFFI Efficiency V IN = 3V, I OUT =100mA 78 % f OSC Switching Frequency V IN = 3.6V , I OUT = 100mA 360 kHz V EN EN Voltage High Enable V IN /2 V PS3120A-GV2.3 PS3120A PULAN TECHNOLOGY CO., LIMITED PULAN TECHNOLOGY

TTyyppiiccaall PPeerrffoorrmmaannccee CChhaarraacctteerriissttiiccss Operating Conditions: TA=25℃, V EN = V IN , C IN = C OUT = C FLY = 10μF, unless otherwise noted. Output Voltage vs. Supply Voltage (ILOAD=0mA) 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 5.1 5.2 Supply Voltage (V) Output Voltage (V) Supply Current vs. Supply Voltage (ILOAD=0mA) Supply Voltage (V) Supply Current (mA) Efficiency vs. Output Current 50 100 150 200 250 300 Output Current (mA) Efficiency (%) V IN =3V V IN =4.2V V IN =3.6V Output Voltage vs. Output Current 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 50 100 150 200 250 300 Output Current (mA) Output Voltage (V) V IN =3V V IN =4.2V V IN =3.6V PS3120A-GV2.3 PS3120A PULAN TECHNOLOGY CO., LIMITED PULAN TECHNOLOGY

Output Noise（V IN =3.6V, I LOAD =100mA） S W N o i s e （V IN =3.6V, I LOAD =100mA） Oscillator Frequency vs.Supply Voltage (ILOAD=100mA) 100 150 200 250 300 350 400 450 500 Supply Voltage (V) Oscillator Frequency (kHz) PS3120A-GV2.3 PS3120A PULAN TECHNOLOGY CO., LIMITED PULAN TECHNOLOGY

Output Noise（V IN =4.2V, I LOAD =100mA） S W N o i s e （V IN =4.2V, I LOAD =100mA） PS3120A-GV2.3 PS3120A PULAN TECHNOLOGY CO., LIMITED PULAN TECHNOLOGY

VOUT (Pin 1): Regulated Output Voltage. VOUT should be bypassed with a low ESR ceramic capacitor providing at least 2.2μF of capacitance as close to the pin as possible for best performance. GND (Pin 2): Ground. These pins should be tied to a ground plane for best performance. EN (Pin 3): Active Low Shutdown Input. This pin must not be allowed to float. C- (Pin 4): Flying Capacitor Negative Terminal. VIN (Pin 5): Input Supply Voltage. VIN should be bypassed with a low ESR ceramic capacitor providing at least 2.2μF of capacitance as close to the pin as possible for best performance. C+ (Pin 6): Flying Capacitor Positive Terminal. BBlloocckk DDiiaaggrraamm PS3120A-GV2.3 PS3120A PULAN TECHNOLOGY CO., LIMITED PULAN TECHNOLOGY

AApppplliiccaattiioonn IInnffoorrmmaattiioonn Operation The PS3120A use a switched capacitor charge pump to boost VIN to a regulated output voltage. Regulation is achieved by sensing the output voltage through an internal resistor divider and modulating the charge pump output current based on the error signal. A 2-phase nonoverlapping clock activates the charge pump switches. The flying capac itor is charged from VIN on the first phase of the clock. On the second phase of the clock it is stacked in series with VIN and connected to VOUT. This sequence of charging and discharging the flying capacitor continues at a free running frequency of 360kHz (typ). In shutdown mode all circuitry is turned off and t he PS3120A draw only leakage current from the VIN supply. Furthermore, VOUT is disc onnected from VIN. The EN pin is a CMOS input with a threshold voltage of approximately 0.8V. The PS3120A is in s hutdown when a logic low is applied to the EN pin. Since the EN pin is high impedance CM OS input it should never be allowe d to float. To ensure that its state is defined it must always be driven with a valid logic level. VIN, VOUT Capacitor Selection The style and value of capacitors used with the PS3120A determine several important parameters such as regulator control loop stability, output ripple, charge pump strength and minimum start-up time. To reduce noise and ripple, it is recommended that low ESR (< 0.1 Ω) ceramic capacitors be used for both C IN and C OUT . These capacitors should be greater than 2.2μF. Tantalum and aluminum capacitors are not recommended because of their high ESR. Flying Capacitor Selection Warning: A polarized capacitor such as tantalum or aluminum should never be used for the flying capacitor since its voltage can reverse upon start-up of the PS3120A . Low ESR ceramic capacitors should always be used for the flying capacitor. The flying capacitor controls the strength of the charge pump. In or der to achieve the rated output current it is necessary to have more than 2.2μF of capacitance for the flying capacitor. Layout Considerations Due to its high switching frequency and the high tr ansient currents produced by the PS3120A, careful board layout is necessary. A true ground plane and s hort connections to all capacitors will improve performance and ensure proper regulation under all conditions. Figure 2 shows an example layout for the PS3120A. Figure 2: Recommended Layout PS3120A-GV2.3 PS3120A PULAN TECHNOLOGY CO., LIMITED PULAN TECHNOLOGY

PPaacckkaaggiinngg IInnffoorrmmaattiioonn Symbol Dimensions In Millimeters Dimensions In Inches Min Max Min Max A 1.050 1.250 0.041 0.049 A1 0.000 0.100 0.000 0.004 A2 1.050 1.150 0.041 0.045 b 0.300 0.500 0.012 0.020 c 0.100 0.200 0.004 0.008 D 2.820 3.020 0.111 0.119 E 1.500 1.700 0.059 0.067 E1 2.650 2.950 0.104 0.116 e 0.950(BSC) 0.037(BSC) e1 1.800 2.000 0.071 0.079 L 0.300 0.600 0.012 0.024 θ 0° 8° 0° 8° PS3120A-GV2.3 PS3120A PULAN TECHNOLOGY CO., LIMITED PULAN TECHNOLOGY