FSDH321LX Fairchild Semiconductor, FSDH321LX Datasheet
FSDH321LX
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FSDH321LX Summary of contents
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... FSDx321 devices reduce total component count, design size, weight while increasing efficiency, productivity and system reliability. Both devices provide a basic platform that is well suited for the design of cost-effective flyback converters. FPS is a trademark of Fairchild Semiconductor Corporation. TM ©2005 Fairchild Semiconductor Corporation www.fairchildsemi.com OUTPUT POWER TABLE (3) 230VAC ± ...
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FSDH321, FSDL321 Internal Block Diagram + V - BURH V /V BURL BURH Vcc Vcc I I Vfb DELAY FB 3 2.5R Ipk 4 Soft Start V SD Vcc Vovp TSD 2 Vcc 2 8V/12V Vcc Freq. Modulation I BUR(pk) ...
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... Sense FET source terminal on primary side and internal control ground. Positive supply voltage input. Although connected to an auxiliary transform- er winding, current is supplied from pin 5 (Vstr) via an internal switch during startup (see Internal Block Diagram section not until Vcc reaches the UVLO upper threshold (12V) that the internal start-up switch opens and de- vice power is supplied via the auxiliary transformer winding ...
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FSDH321, FSDL321 Absolute Maximum Ratings (Ta=25°C, unless otherwise specified) Characteristic Drain Pin Voltage Vstr Pin Voltage Drain-Gate Voltage Gate-Source Voltage (1) Drain Current Pulsed Continuous Drain Current (Tc=25℃) Continuous Drain Current (Tc=100℃) Single Pulsed Avalanche Energy Supply Voltage Feedback Voltage ...
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... Gate-Source Charge Gate-Drain (Miller) Charge CONTROL SECTION Switching Frequency Switching Frequency Modulation Switching Frequency Switching Frequency Modulation Switching Frequency Variation Maximum Duty Cycle UVLO Threshold Voltage Feedback Source Current Internal Soft Start Time BURST MODE SECTION Burst Mode Voltage PROTECTION SECTION ...
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FSDH321, FSDL321 Comparison Between FSDM311 and FSDx321 Function Soft-Start 15ms External Current Limit not applicable Frequency Modulation not applicable Burst Mode Operation Built into controller Drain Creepage at 7.62mm Package 6 FSDM311 FSDx321 15ms Programmable of default current limit ±3.0KHz ...
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Typical Performance Characteristics (Control Part) (These characteristic graphs are normalized 1.20 1.00 0.80 0.60 0.40 0.20 0.00 - emp[ ℃ ] Operating Frequency (Fosc) vs. Ta 1.20 1.00 0.80 0.60 0.40 0.20 0.00 -50 ...
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FSDH321, FSDL321 Typical Performance Characteristics 1.20 1.00 0.80 0.60 0.40 0.20 0.00 - emp[ ℃ ] Feedback Source Current (I 1.20 1.00 0.80 0.60 0.40 0.20 0.00 - emp[ ℃ ] Peak Current Limit (I 1.20 ...
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... Vstr pin had an external resistor to the DC input voltage line. In this generation the startup resistor is replaced by an internal high voltage current source and a switch that shuts off when 15ms goes by after the supply voltage, Vcc, gets above 12V. The source turns back on if Vcc drops below 8V. ...
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... In general, Vcc is proportional to the output volt- age and the FPS uses Vcc instead of directly monitoring the output voltage resulting in termination of the switching operation. In order to avoid undesired activation of OVP during normal opera- tion, Vcc should be properly designed to be below 19V. PWM ...
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... V V Waveform Vfb t 7. Frequency Modulation : Modulating the switching fre- quency of a switched power supply can reduce EMI. Fre- quency modulation can reduce EMI by spreading the energy over a wider frequency range than the bandwidth measured voltage drops below by the EMI test equipment. The amount of EMI reduction is directly related to the depth of the reference frequency ...
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FSDH321, FSDL321 Frequency (MHz) Figure 11. KA5-series FPS Full Range EMI scan(67KHz, no Frequency Modulation) with DVD Player SET Frequency (MHz) Figure 12. FSDX-series FPS Full Range EMI Scan (67KHz, with Frequency Modulation) with DVD Player SET 12 8. Adjusting ...
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... Application Tips 1. Methods of Reducing Audible Noise Switching mode power converters have electronic and magnetic components, which generate audible noises when the operating frequency is in the range of 20~20,000 Hz. Even though they operate above 20 kHz, they can make noise depending on the load condition. Designers can employ several methods to reduce these noises ...
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FSDH321, FSDL321 Typical Application Circuit Application Output power PC Auxiliary Power Supply Features • High efficiency (>70% at full load, full input range) • Low standby mode power consumption (< 375V input and 0.5W load) • Low component ...
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Transformer Schematic Diagram Vcc Winding Specification → tio n : ...
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FSDH321, FSDL321 6. Demo Circuit Part List Part Value Resistor R101 680K R102 100K R103 10 R104 10 R201 1K R202 330 R203 2K R204 2K Capacitor C101 10nF/630V C102 47uF/50V C103 10uF/50V C104 22nF/50V C201 1000uF/16V C202 100nF/50V C203 ...
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Package Dimensions 8DIP FSDH321, FSDL321 17 ...
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FSDH321, FSDL321 Package Dimensions 18 (Continued) 8LSOP ...
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Ordering Information Product Number Package FSDH321 8DIP FSDL321 8DIP FSDH321L 8LSOP FSDL321L 8LSOP Marking Code BV DSS DH321 650V DL321 650V DH321 650V DL321 650V FSDH321, FSDL321 f R OSC DS(ON) 100KHz 14Ω 50KHz 14Ω 100KHz 14Ω 50KHz 14Ω 19 ...
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... FSDH321, FSDL321 DISCLAIMER FAIRCHILD SEMICONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICE TO ANY PRODUCTS HEREIN TO IMPROVE RELIABILITY, FUNCTION OR DESIGN. FAIRCHILD DOES NOT ASSUME ANY LIABILITY ARISING OUT OF THE APPLICATION OR USE OF ANY PRODUCT OR CIRCUIT DESCRIBED HEREIN; NEITHER DOES IT CONVEY ANY LICENSE UNDER ITS PATENT RIGHTS, NOR THE RIGHTS OF OTHERS. ...