SE5562F Philips Semiconductors, SE5562F Datasheet
SE5562F
Related parts for SE5562F
SE5562F Summary of contents
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... Demagnetization/overvoltage protection Duty cycle adjust and clamp Feed-forward control External synchronization Total shutdown after adjustable number of overcurrent faults Soft-start TEMPERATURE RANGE ORDER CODE 0 to +70 C NE5562D 0 to +70 C NE5562N - +125 C SE5562F 1 Product specification NE/SE5562 S SL00388 DWG # 1021B SOT146-1 SOT146-1 853-0811 13721 ...
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... Philips Semiconductors Switched-mode power supply control circuit BLOCK DIAGRAM FEEDFORWARD + + – – + OFF ON REMOTE ON/OFF 6 ERROR AMP OUT 10 3.80V + FEEDBACK – VOLTAGE 8 ERROR AMP – 0.955V + LOOP FAULT COMP EXTERNAL MOD 4 IN DUTY CYCLE CONTROL 5 OC CHARGE PUMPS 1:1 1:1 C DELAY ...
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... Philips Semiconductors Switched-mode power supply control circuit ABSOLUTE MAXIMUM RATINGS SYMBOL Supply V voltage-fed mode (Pin 17 current-fed mode (Pin 7) CC Output transistor output current Sync (Pin 11) Duty cycle control (Pin 5) Remote on/off (Pin 6) Output invert control (Pin 15) Feedback pin (Pin 8) C (Pin 16) ...
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... Philips Semiconductors Switched-mode power supply control circuit DC AND AC ELECTRICAL CHARACTERISTICS V = 12V, specifications apply over temperature, unless otherwise specified. CC SYMBOL SYMBOL PARAMETER PARAMETER Reference V Zener voltage Z V Zener voltage Temperature stability Z Low supply shutdown Comparator threshold voltage Comparator threshold voltage Hysteresis Oscillator ...
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... Philips Semiconductors Switched-mode power supply control circuit DC AND AC ELECTRICAL CHARACTERISTICS V = 12V, specifications apply over temperature, unless otherwise specified. CC SYMBOL SYMBOL PARAMETER PARAMETER Error amp I Input bias current BIAS A DC open-loop gain VOL V High output voltage OH V Low output voltage OL PSRR from V ...
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... Philips Semiconductors Switched-mode power supply control circuit DC AND AC ELECTRICAL CHARACTERISTICS V = 12V, specifications apply over temperature, unless otherwise specified. CC SYMBOL SYMBOL PARAMETER PARAMETER Auxiliary comparator with shutdown I Bias current BIAS Threshold voltage C Discharge current DELAY Hysteresis Demagnetization overvoltage comparator I Bias current BIAS ...
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... Philips Semiconductors Switched-mode power supply control circuit 100 100 100 1994 Aug 31 CLOSED-LOOP GAIN 1k 10k 100k 1M FREQUENCY Figure 4. Error Amplifier Closed-Loop Response = 12V = PWM INPUT VOLTAGE (V) Figure 5. Duty Cycle vs PWM Input Voltage FEED-FORWARD VOLTAGE (V) Figure 6. Duty Cycle vs Feed-forward Voltage 7 Product specification ...
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... Philips Semiconductors Switched-mode power supply control circuit 1994 Aug SUPPLY VOLTAGE (PIN 17)(V) Figure 7. Current-Feed Characteristics = SUPPLY VOLTAGE (PIN 17)(V) Figure 8. Voltage-Feed Characteristics 8 Product specification NE/SE5562 SL00394 SL00395 ...
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... Philips Semiconductors Switched-mode power supply control circuit THE NE/SE5562 THEORY OF OPERATION INTRODUCTION Switched-mode power conversion relies on the principle of pulsed energy storage in an inductive or capacitive element. Capacitive switched converters are typically used with low power systems for which only tens of milliamperes are required. Medium and high ...
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... Philips Semiconductors Switched-mode power supply control circuit FEED- FORWARD +7.50V 3 2 CURRENT STEERING VOLTAGE FEEDBACK 8 THE NE/SE5562 THEORY OPERATION The Sawtooth Oscillator The sawtooth oscillator consists of a gated charge-discharge capacitor circuit with threshold comparators setting the peak and valley voltages of the ramp. The resistor divider R1-3 is supplied with a source voltage derived from either V (7 ...
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... Philips Semiconductors Switched-mode power supply control circuit 35 A SAWTOOTH + V REF +3.80V + 8 – Figure 16. The Duty Cycle Control Circuit, Pulse Width Modulator, and Error Amplifier, Reference, and Output Latch 1994 Aug (–) (–) ERROR SAWTOOTH AMP UPPER OUT THRESHOLD 9k 2.5k 100 A Figure 15. PWM Comparator ...
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... Philips Semiconductors Switched-mode power supply control circuit PIN 14 Figure 17. Duty Cycle vs Feedback Error and Overcurrent Sense The error amplifier’s non-inverting input is tied to a bandgap reference of 3.80V, accurate The temperature stability of the voltage reference is 30ppm/ C. The error amplifier is designed for an open-loop gain of 86dB having a small-signal unity gain bandwidth of 3MHz ...
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... Philips Semiconductors Switched-mode power supply control circuit OFFSET 50 ADJUST 360 FEED-FORWARD COMPENSATION (PIN 1) To provide a means of automatically improving line-to-load voltage regulation, a technique called feed-forward regulation is made a part of the NE/SE5562 active mechanism. Referring back to the diagram for the sawtooth oscillator, note that Pin 1 is capable of changing the ...
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... Philips Semiconductors Switched-mode power supply control circuit V FFWD 2N3906 220k 0 NE/SE5562 Figure 21. Feed-forward Turn-On Delay Circuit + SYNC PIN 11 SYNC SIGNAL T O Figure 23. Sync Signal Relationship to Controlled Sawtooth Waveform DUTY CYCLE LIMIT (PIN 5) The forward or buck converter, and even the flyback converters, may require an automatic duty cycle limit to prevent transformer saturation or unstable behavior ...
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... Philips Semiconductors Switched-mode power supply control circuit 2. Slow-start if remote ON/OFF is actuated, if OC2 threshold trips, demagnetization/overvoltage is sensed, or low supply voltage to the internal regulator is sensed (VS 8.45V). 3. Note that Pin 8 is monitored by the loop fault comparator. When the regulated supply feedback drops below this threshold level (0 ...
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... Philips Semiconductors Switched-mode power supply control circuit 0.1 0.2 0.3 0.6 0.7 0.4 0.5 Figure 25. Maximum Duty Cycle LOW SUPPLY SENSE R73 R74 10k 10k Q262 Q264 Q266 Q260 OC ACCUM Q265 Q261 Q267 Q263 SHUTDOWN LATCH BULK SENSE + 1994 Aug 7.50 V ...
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... Philips Semiconductors Switched-mode power supply control circuit THE START-STOP CONTROL SEQUENCE The start-up circuit involves a sequential set of conditions which progresses as follows: power-up after OFF condition or remote ON after OFF. Initially, 0V exist on the supply output, causing zero feedback volts on Pin 8. The slow-start capacitor is discharged, forcing Pin 5 to 0V, having been clamped by the internal discharge transistor ...
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... Philips Semiconductors Switched-mode power supply control circuit DUAL-LEVEL OVERCURRENT COMPARATORS The overcurrent sensing circuit (Figure 29) consists of a single PNP input buffer with emitter-follower tied 7.50V, feeding into the Z base of an NPN split-emitter transistor. This forms the input node to a set of dual-level voltage comparators with references of 0.528 and ...
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... Philips Semiconductors Switched-mode power supply control circuit sawtooth oscillator. The complete sequence for an overcurrent fault may be understood by referring to Figure 32 for OC2. Here it is shown that an OC2 signal exists indicating that the 0.65V threshold has been exceeded by a signal at Pin 14. Note that an overcurrent pulse within a particular clock frame turns ...
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... Philips Semiconductors Switched-mode power supply control circuit 3.86V 0 DELAY 0.00V 100 200 OC1 DELAY TIME (MILLISECONDS) 3.66V DELAY 0.00V OC2 DELAY TIME (MILLISECONDS) (neglecting recycle dfelay) Figure 33. Overcurrent Shutdown Function CALCULATING THE DELAY CAPACITOR Actual delay time for a given capacitor value at Pin 16 may be estimated using the graphs in Figure 33 for OC1 and OC2 ...
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... Philips Semiconductors Switched-mode power supply control circuit 8 (3 )(3.86V) Delay Time =10.7ms 3 10 Total cycles shutdown 6 2 =4280 Figure 35 shows an actual OC1 charging cycle for continuous fault current sensed at Pin 14 and a DLY = 1 F. BULK-SENSE AUXILIARY COMPARATOR WITH SHUTDOWN This circuit is intended to act as an automatic low-line detection mechanism ...
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... Q148 Q140 Q149 Q150 INVERT 15 NORM Figure 37. Output Driver Schematic 20-Pin glass/ceramic—NE5562F/ SE5562F: 20-Pin SO: -55 to +85 C/W (board-dependent) 1 NOTE: 1. See Figures 7 and 8 for internal Regulator Response Curves. Design Example—An NE5562N is operated ambient in the voltage-fed mode with V . Drive currents Z ...
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... Philips Semiconductors Switched-mode power supply control circuit V S VOLTAGE SOURCE V I CURRENT SOURCE - ( (15) D =330mW Solving for the temperature rise from ambient to the IC functions: Temperature rise = 61 C/W 0.33W = 20 10k (0.472 10k ‘A’ VARIABLE SUPPLY 0-5V NOTES: 1. Supply will become active as point ‘A’ reaches the level ...
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... Philips Semiconductors Switched-mode power supply control circuit + V IN – NOTE: The P clamp winding prevents collector voltage from exceeding – Prevent Core Saturation Due to Flux Staircasing max m max Demagnetization of Core CEmax imax Maximum Voltage Across Transistor Figure 42. Forward Converter Design Formulas – ...
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... Philips Semiconductors Switched-mode power supply control circuit Frequency of Operation Estimate of Overall Efficiency 0. FWD SENSE 2N3906 40k 220k 10k 0. (PIN 9) V CLOCK Z 2 DELAY 7.50V 5.1k 570 pF 4 13k 3.26V 5 PWM 10k OFF 3.80V +5V REMOTE 0V + SHUT DOWN ON ERROR AMP 1.3k ...
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... Philips Semiconductors Switched-mode power supply control circuit 33k 220k 6.8k 0. Figure 45. Shunt-Regulated Output With Bootstrap Supply 1994 Aug 31 +48V +17V 100 15V D40K2 NE/SE5562 n +3.80V 19 + – Product specification NE/SE5562 +V O +5V n/2 SL00432 ...
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... Philips Semiconductors Switched-mode power supply control circuit Development of Practical Flyback Converter Circuit TR1 NOTES: a. Unlimited choke current Flyback Converter and Current and Voltage Waveforms b. Interrupted choke current 1994 Aug – CURRENT PATH CURRENT PATH V WITH SWITCH WITH SWITCH I CLOSED OPEN – ...
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... Philips Semiconductors Switched-mode power supply control circuit 2N3906 0. SENSE 0’ 570pF + 3. NOTE: 400kHz operation with feed-forward line regulation and cycle-by-cycle current timing. 100 +3.80V I ’ Figure 48. Negative Output Regulator Using Current Mirror 1994 Aug 31 48V +V S 33k +12V FEED- 220k FORWARD ...
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... Philips Semiconductors Switched-mode power supply control circuit –15V +15V NE5018 D/A P REFERENCES 1. R.D. Middlebrook and Slobadan Cuk, Advances in Switched Mode Power Conversion, Volumes I and II, TESLA Co., Pasa- dena, CA, 1983. 2. Rudolf P. Stevens and Gordon E. Bloom, Modern Switchmode Power Convertor Circuits, Van Nostrand Reinhold/ Computer Science and Engineering Series, 1985 ...