PSB2121-P Siemens Semiconductor Group, PSB2121-P Datasheet
PSB2121-P
Related parts for PSB2121-P
PSB2121-P Summary of contents
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General-Purpose Power Controller (GPPC) Features Switched mode DC/DC-converter CCITT ISDN compatible Low power dissipation Supply voltage range Programmable input undervoltage protection Programmable overcurrent protection Soft start Power housekeeping input Oscillator synchronization input/output High voltage CMOS-technology 70 ...
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The PSB 2121 Contains the Following Functional Blocks Undervoltage lockout Temperature compensated voltage reference Sawtooth oscillator Error amplifier Pulse width modulator Digital current limiting Soft start Double pulse inhibit Power driver Together with few external components it provides a stable ...
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Pin Definitions and Functions Pin No. Pin No. Symbol Input (I) P-DSO P-DIP REF GND EXT ...
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Figure 1 GPPC Functional Diagram Semiconductor Group 4 PSB 2121 ...
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Absolute Maximum Ratings Parameter Supply voltage (pin V ) referred to GND S Analog input voltage (pins PWMP SYNC, OR, OC referred to GND Reference output current (pin ...
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DC-Characteristics (cont’d) Parameter Oscillator / SYNC / kHz OSC T Initial accuracy ˚C A Voltage stability Temperature stability Max. frequency Sawtooth peak voltage Sawtooth valley voltage H-sync output level ...
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DC-Characteristics (cont’d) Parameter Pulse Width Modulator Duty cycle Under Voltage Detection UV Start up threshold Threshold hysteresis C Soft Start SS Charging current Output Driver ˚C A H-output voltage L-output voltage Rise time Fall time Output ...
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Application Informations Undervoltage Lockout The undervoltage lockout circuit protects the PSB 2121 and the power devices from inadequate supply voltage too low, the circuit disables this output driver. This ensures that all control S functions have been ...
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At the beginning of the discharge period a positive synchronization pulse is generated at pin SYNC. Otherwise the PSB 2121 can be synchronized via pin SYNC to an external logic clock by programming the oscillator to free run at a ...
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Pulse Width Modulator The pulse width modulator compares the sawtooth-voltage of the oscillator output with the input signal at PWMP and with the voltage of the external soft start capacitor at Error Amplifier Conventional operational amplifier for closed-loop gain and ...
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Extended Input Voltage Range Some DC/DC-converter applications require a higher input voltage than the maximum supply voltage of the PSB 2121 which is limited Figure 4 shows a method to extend the input voltage range by connecting ...
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Figure 5 Application Circuit Semiconductor Group 12 PSB 2121 ...
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Figure 6 Application Circuit Semiconductor Group 13 PSB 2121 ...