MC33025 Motorola, MC33025 Datasheet
MC33025
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MC33025 Summary of contents
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... Flip Flop Output A Power Ground 12 9 MC33025DW Current MC33025P Limit/ Shutdown MC34025DW Ground MC34025P Motorola, Inc. 1996 Order this document by MC34025/D MC34025 MC33025 SUFFIX PLASTIC PACKAGE CASE 648 SUFFIX PLASTIC PACKAGE CASE 751G (SO–16L) PIN CONNECTIONS Error Amp ref ...
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... NOTES: 1. Maximum package power dissipation limits must be observed. 2. Low duty cycle pulse techniques are used during test to maintain junction temperature as close to ambient as possible for MC34025 T = +70 C for MC34025 low high T = – for MC33025 T = +105 C for MC33025 low high 2 MC34025 MC33025 Symbol Value ...
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... NOTES: 1. Maximum package power dissipation limits must be observed. 2. Low duty cycle pulse techniques are used during test to maintain junction temperature as close to ambient as possible for MC34025 T = +70 C for MC34025 low high T = – for MC33025 T = +105 C for MC33025 low high MOTOROLA ANALOG IC DEVICE DATA MC34025 MC33025 Symbol Min V IO – ...
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... FREQUENCY (Hz) Figure 5. Error Amp Small Signal Transient Response 2.55 V 2.5 V 2.45 V 0.1 s/DIV 4 MC34025 MC33025 Figure 2. Oscillator Frequency versus Temperature 1200 1000 800 600 400 200 – 55 – 25 Figure 4. PWM Comparator Zero Duty Cycle Threshold Voltage versus Temperature 1 ...
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... Change versus Temperature 4.0 2.0 0 – 2.0 – 4.0 – 6.0 – 8.0 –10 –12 – 50 – AMBIENT TEMPERATURE ( C) MOTOROLA ANALOG IC DEVICE DATA MC34025 MC33025 Figure 8. Reference Short Circuit Current 65.6 65 64.8 64 –55 – 25 Figure 10. Reference Load Regulation Figure 12. Shutdown Comparator Threshold 1. ...
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... Figure 15. Drive Output Rise and Fall Time OUTPUT RISE & FALL TIME 1.0 nF LOAD 50 ns/DIV Figure 17. Supply Voltage versus Supply Current 5 MC34025 MC33025 Figure 14. Output Saturation Voltage 0 –1 Pulsed Load 120 Hz Rate –2 2.0 1 ...
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... Noninverting Input Inverting Input 1 8 Soft–Start Clock Soft–Start Error Amp Output Ramp PWM Comparator Output A Output B MOTOROLA ANALOG IC DEVICE DATA MC34025 MC33025 Figure 18. Representative Block Diagram Reference Regulator V CC UVLO 4 ref UVLO Steering ...
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... The MC33025 and MC34025 series are high speed, fixed frequency, double–ended pulse width modulator controllers optimized for high frequency operation. They are specifically designed for Off–Line and DC–to–DC converter applications offering the designer a cost effective solution with minimal external components ...
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... The PC board lead lengths must be less than 0.5 inches for effective bypassing or snubbing. MOTOROLA ANALOG IC DEVICE DATA MC34025 MC33025 Instabilities In current mode control, an instability can be encountered at any given duty cycle. The instability is caused by the current feedback loop ...
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... Output Voltage Feedback Input 2 V ref In voltage mode operation, the control range on the output of the Error Amplifier from 0% to 90% duty cycle is from 2. 4. MC34025 MC33025 PIN FUNCTION DESCRIPTION Description Figure 22. Current Mode Operation C T From Current Sense Element ...
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... The addition filter will eliminate instability caused by the leading edge spike on the current waveform. This sense signal can also be used at the ramp input pin for current mode control. For ramp compensation it is necessary to know the gain of the current feedback loop. The gain can be calculated by: MOTOROLA ANALOG IC DEVICE DATA MC34025 MC33025 Figure 24. External Clock Synchronization 5.0 V ...
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... The diode provides a reset pulse at the ramp input at the end of every cycle. The charge current I M can be calculated Then R M can be calculated Figure 29. Current Mode Master/Slave Operation Over Short Distances Oscillator 12 MC34025 MC33025 4 5 Oscillator 6 ...
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... MC34025 470 680 pF 562 MMBT3904 100 Provides Leading Edge Blanking MOTOROLA ANALOG IC DEVICE DATA MC34025 MC33025 Synchronizes Both Converters to the Same Phase 20 4.7 k 1.0 k MMBT3906 4700 10 k MMBT3904 MMBD914 Output Output B 470 pF 680 pF 562 100 k MC34071 1 ...
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... The totem pole output can easily drive pulse transformers. A Schottky diode is recommended when driving inductive loads at high frequencies. The diode can reduce the driver’s power dissipation due to excessive ringing, by preventing the output pin from being driven below ground MC34025 MC33025 Figure 32. Bipolar Transistor Drive Base Charge – Removal Q T ...
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... MOTOROLA ANALOG IC DEVICE DATA MC34025 MC33025 Figure 36. Keeps Fig numbering sequence correct 15 ...
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... Figure 37. PC Board With Components 100 pF 1N5819 1000 pF 0.01 1N5819 16 MC34025 MC33025 6.5 (Top View) MOTOROLA ANALOG IC DEVICE DATA 1500 pF 4.0 1500 ...
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... Figure 38. PC Board Without Components MOTOROLA ANALOG IC DEVICE DATA MC34025 MC33025 (Top View) 6.5 (Bottom View) 4.0 17 ...
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... 0.25 (0.010) –A– –B– 0.25 (0.010 MC34025 MC33025 OUTLINE DIMENSIONS P SUFFIX PLASTIC PACKAGE CASE 648– SEATING –T– PLANE SUFFIX PLASTIC PACKAGE CASE 751G–02 (SO–16L ...
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... PROTRUSION OR INTRUSION. THE DAMBAR PROTRUSION(S) SHALL NOT CAUSE THE H DIMENSION TO BE GREATER THAN 0.037 (0.940). THE DAMBAR INTRUSION(S) SHALL NOT CAUSE THE H DIMENSION TO BE SMALLER THAN 0.025 (0.635). MOTOROLA ANALOG IC DEVICE DATA MC34025 MC33025 OUTLINE DIMENSIONS FN SUFFIX PLASTIC PACKAGE CASE 775–02 (PLCC) B 0.007 (0.180 – ...
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... US & Canada ONLY 1–800–774–1848 51 Ting Kok Road, Tai Po, N.T., Hong Kong. 852–26629298 INTERNET: http://motorola.com/sps 20 MC34025 MC33025 are registered trademarks of Motorola, Inc. Motorola, Inc Equal JAPAN: Nippon Motorola Ltd.: SPD, Strategic Planning Office, 4–32–1, Nishi–Gotanda, Shinagawa–ku, Tokyo 141, Japan. 81–3–5487–8488 ASIA/PACIFIC: Motorola Semiconductors H.K. Ltd. ...