ZXSC100 Zetex Semiconductors plc., ZXSC100 Datasheet
ZXSC100
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ZXSC100 Summary of contents
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... SINGLE CELL DC-DC CONVERTER SOLUTION DESCRIPTION The ZXSC100 series is designed for DC-DC applications where step-up voltage conversion from very low input voltages is required. These applications mainly operate from single nickel cadmium or nickel metal hydride battery cells. The circuit can start up under full load with regulation maintained down to an input voltage of only 0 ...
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... ZXSC100 ABSOLUTE MAXIMUM RATING Supply voltage 0.3 to 3.5V Maximum voltage other pins 0 Power dissipation (25°C) MSOP8 500mW SO8 780mW ELECTRICAL CHARACTERISTICS (Unless otherwise stated) V Symbol Parameter I Quiescent current CC I Base drive current DRIVE V V o/p voltage DRIVE DRIVE V Feedback voltage FB V Output current reference ...
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... TYP. MAX (BR)CEO CE(sat) 70 100 150 200 = 25°C unless otherwise stated) amb MIN. TYP. MAX. UNIT 500 mV µA 100 ZXSC100 Typ Max Units 200 kHz UNIT CONDITIONS V I =10mA =0.1A, I =10mA =1A, I =10mA =3A, I ...
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... ZXSC100 TYPICAL CHARACTERISTICS 300 250 200 150 100 1.0 1.5 Input Voltage (V) Quiescent Current v Input Voltage 2.0 1.5 1.0 0.5 0.0 -0.5 -1.0 -1.5 -2.0 0 50m Output Current (A) Load Regulation 2.0 1.5 1.0 0.5 0.0 -0.5 -1.0 -1.5 -2.0 -10 0 2.0 2.5 Output Voltage v Temperature 5.0 2.5 0.0 -2.5 -5.0 100m 1 Temperature (°C) 1.5 2.0 2.5 Input Voltage (V) Line Regulation ...
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... DEVICE DESCRIPTION The ZXSC100 is non-synchronous PFM, DC-DC controller IC which, when combined with a high performance external transistor, enables the production of a high efficiency boost converter for use in single cell applications. A block diagram is shown for the ZXSC100 in Figure Shutdown Comp1 R1 V REF R2 Comp2 ...
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... ZXSC100 PIN DESCRIPTIONS Pin Name Description No Emitter of internal drive transistor. Connect lower power applications. Must be unconnected in higher power applications 2 BAS Not connected in lower power applications. Connect to base of external drive transistor in higher power applications 3 RE Drive current sense input. Internal threshold voltage set 25mV below V external sense resistor ...
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... Size Various 0805 Size Various 0805 Size Various 0805 Size AVX Low ESR tantalum capacitor AVX Low ESR tantalum capacitor Various 0805 Size Coilcraft Low profile SMT 7 ZXSC100 D1 3.3V/0.1A ZHCS1000 Q1 R3 FMMT617 ...
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... FMMT617 DRIVE I BAS SENSE ZXSC100 R2 C1 MATERIALS LIST Ref Value Part Number U1 N/A ZXSC100X8 Q1 FMMT617 20V, 13mΩ N/A 2N2907 D1 0.5V, 2A ZHCS1000 R1 3.3Ω* Generic R2 Generic 33mΩ R3 110kΩ Generic R4 Generic 30kΩ C1 220µF TPSD227M010R0100 C2 220µF ...
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... CC ND ZXSC100 Driving white LED’ flashlight application The ZXSC100 solution is ideal for LED lamp driving applications operating from a single cell. In principal conversion from 1.2V to the 3.6V, typically required by white LEDs, is necessary. Load currents in the region of 20mA to 50mA being required for a single LED element. ...
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... ZXSC100 APPLICATIONS INFORMATION The following section is a design guide for optimum converter performance. Switching transistor selection The choice of switching transistor has a major impact on the DC-DC converter efficiency. For optimum performance, a bipolar transistor with low V and high gain is required. The majority of losses in the transistor are, ‘ ...
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... RIPPLE current ripple of the solution. The ESR of the output capacitor can also affect loop stability and transient performance. The capacitors selected for the solution, and indicated in the reference designs, are optimised to provide the best overall performance. 11 ZXSC100 , T and ON DIS DIS T OFF ...
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... I ESR. Output voltage adjustment The ZXSC100 is an adjustable converter allowing the end user the maximum flexibility in output voltage selection. For adjustable operation a potential divider network is connected as indicated in the diagram. ...
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... Also the sense resistor R2 should be connected, with minimum trace length, between emitter lead of Q1 and ground, again minimising stray parasitics. The layout for the 0.33W solution is shown below. Drill holes Bottom Copper 13 ZXSC100 Actual Size ...
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... Efficiency is often quoted as one of the key parameters of a DC-DC converter. Not only does it give an instantaneous idea of heat dissipation, but also an idea as to the extent battery life can be extended. Figure 2. Shows the efficiency of the ZXSC100 low power solution. Efficiency v Output current is shown for a 3.3V output at various input voltages. L1 ...
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... Schottky diode, D1. The diode current is equivalent to this ramp-down current and is shown in figure 7. Figure 5. Inductor current (200mA/div) Figure 6. Transistor current (200mA/div) ISSUE 3 - JANUARY 2004 Figure 7. Diode current (200mA/div) 15 ZXSC100 ...
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... Figure 8. Output voltage ripple for 3.3V/100mA output. Transient response Transient response to step changes in load is a critical feature in many converter circuits. The ZXSC100 operates a pulse by pulse regulation scheme and therefore corrects for changes in the output every pulse cycle, giving excellent response characteristic. ...
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... Asia Pacific Zetex (Asia) Ltd 3701-04 Metroplaza Tower 1 Hing Fong Road, Kwai Fong Hong Kong Telephone: (852) 26100 611 Fax: (852) 24250 494 asia.sales@zetex.com 17 ZXSC100 θ° Corporate Headquaters Zetex plc Fields New Road, Chadderton ...