lnk302 Power Integrations, Inc., lnk302 Datasheet
lnk302
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lnk302 Summary of contents
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... Lowest cost and component count buck converter solution • Fully integrated auto-restart for short-circuit and open loop fault protection – saves external component costs • LNK302 uses a simplifi ed controller without auto-restart for very low system cost • 66 kHz operation with accurate current limit – allows low cost off-the-shelf 1 mH inductor for up to 120 mA output current • ...
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... LNK302/304-306 BYPASS (BP) 6.3 V FEEDBACK 1. (FB) Figure 2a. Functional Block Diagram (LNK302). BYPASS (BP) 6.3 V FEEDBACK 1. (FB) Figure 2b. Functional Block Diagram (LNK304-306). 2-2 2 Rev. H 12/06 BYPASS PIN UNDER-VOLTAGE + 5 4.85 V JITTER CLOCK DC MAX THERMAL SHUTDOWN OSCILLATOR FAULT PRESENT AUTO- RESTART BYPASS PIN COUNTER ...
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... When the die temperature rises above this threshold (142 °C) the power MOSFET is disabled and remains disabled until the die temperature falls by 75 °C, at which point it is re-enabled. Current Limit The current limit circuit senses the current in the power MOSFET. When this current exceeds the internal threshold (I LNK302/304-306 ), the LIMIT 2-3 3 Rev. H 12/06 ...
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... LNK302/304-306 600 500 V DRAIN 400 300 200 100 0 68 kHz 64 kHz 0 Time (μs) Figure 4. Frequency Jitter. power MOSFET is turned off for the remainder of that cycle. The leading edge blanking circuit inhibits the current limit comparator for a short time (t ) after the power MOSFET LEB is turned on ...
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... LinkSwitch-TN Selection and Selection Between MDCM and CCM Operation Select the LinkSwitch-TN device, freewheeling diode and output inductor that gives the lowest overall cost. In general, MDCM LNK302/304-306 ...
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... LNK302/304-306 TOPOLOGY BASIC CIRCUIT SCHEMATIC High-Side Buck – Direct FB BP Feedback LinkSwitch- High-Side Buck – Optocoupler Feedback LinkSwitch- Low-Side + Buck – Optocoupler LinkSwitch-TN Feedback Low-Side + Buck – Constant LinkSwitch-TN Current LED V IN Driver BP S High-Side Buck Boost – ...
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... Capacitor C3 can be a low cost general purpose capacitor. It provides a “sample and hold” function, charging to the output voltage during the off time of LinkSwitch-TN. Its value should be 10 μ μF; smaller values cause poorer regulation at light load conditions. LNK302/304-306 KEY FEATURES 1. Output referenced to input 2. Positive output (V ) with respect Step up/down – ...
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... LNK302/304-306 Pre-load Resistor R4 In high-side, direct feedback designs where the minimum load is <3 mA, a pre-load resistor is required to maintain output regulation. This ensures suffi cient inductor energy to pull the inductor side of the feedback capacitor C3 to input return via D2. The value of R4 should be selected to give a minimum output load ...
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... DRAIN Voltage .................................. ................ -0 700 V Peak DRAIN Current (LNK302).................200 mA (375 mA) Peak DRAIN Current (LNK304).................400 mA (750 mA) Peak DRAIN Current (LNK305).................800 mA (1500 mA) Peak DRAIN Current (LNK306).................1400 mA (2600 mA) FEEDBACK Voltage .........................................-0 FEEDBACK Current.............................................100 mA BYPASS Voltage ..........................................-0 Storage Temperature .......................................... -65 °C to 150 °C ..................... -40 ° ...
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... T J di/ mA/μ ° LNK304 di/dt = 415 mA/μ ° di/ mA/μ ° LNK305 di/dt = 500 mA/μ ° di/ mA/μ ° LNK306 di/dt = 610 mA/μ ° LNK302/304 LNK305 LNK306 = 25 ° See Note F Min Typ Max Units -5.5 -3.3 -1.8 -7.5 -4.6 -2.5 mA -3.8 -2.3 -1.0 -4.5 -3.3 -1.5 5.55 5.8 6.10 V 0.8 0.95 1 ...
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... LNK305 V = 560 °C T LNK306 6 ≥ ° Measured in a Typical Buck Converter Application See Figure 9 LNK302 = 25 ° See Note H LNK304-306 LNK302 LNK304-306 LNK302/304-306 Min Typ Max Units ° 55.2 76 88.4 24 27.6 38 44.2 Ω 12 13.8 19 22.1 7 8.1 11 12.9 50 μ ...
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... LNK302/304-306 NOTES: A. Total current consumption is the sum of I switching) and the sum of I and Since the output MOSFET is switching diffi cult to isolate the switching current from the supply current at the DRAIN. An alternative is to measure the BYPASS pin current ...
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... Limit = 1 LNK302 55 mA/μs 136 mA LNK304 65 mA/μs 257 mA 0.4 LNK305 75 mA/μs 375 mA LNK306 95 mA/μs 482 mA 0 Normalized di/dt 25 °C 100 °C Scaling Factors: LNK302 0.5 LNK304 1.0 LNK305 2.0 50 LNK306 3 DRAIN Voltage (V) 6 2-13 13 Rev. H 12/06 ...
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... LNK302/304-306 Typical Performance Characteristics (cont.) PART ORDERING INFORMATION LNK 304 2-14 14 Rev. H 12/06 1000 100 Scaling Factors: LNK302 0.5 LNK304 1.0 LNK305 2.0 LNK306 3 100 200 300 400 500 Drain Voltage (V) Figure 16. C vs. Drain Voltage. OSS LinkSwitch Product Family TN Series Number Package Identifi er ...
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... Solder Pad Dimensions .057 (1.45) .068 (1.73) (NOTE 5) .004 (.10) .009 (.23) .004 (.10) .036 (0.91) .012 (.30) .044 (1.12) LNK302/304-306 (NOTE 7) PI-2551-121504 Notes: 1. Controlling dimensions are inches. Millimeter sizes are shown in parentheses. 2. Dimensions shown do not include mold flash or other protrusions. Mold flash or protrusions shall not exceed .006 (.15) on any side. ...
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... LNK302/304-306 B 4 4.90 (0.193) BSC 3.90 (0.154) BSC 0.10 (0.004 Pin 1 ID 1.27 (0.050) BSC 1.35 (0.053) 1.25 - 1.65 1.75 (0.069) (0.049 - 0.065) 0.10 (0.004) 0.25 (0.010) Reference Solder Pad Dimensions 2.00 (0.079 1.27 (0.050) D07C 2-16 16 Rev. H 12/06 SO-8C 0.10 (0.004 SEATING PLANE 6.00 (0.236) BSC 4 0.20 (0.008 0.31 - 0.51 (0.012 - 0.020) 0.25 (0.010 A-B D ...
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... LNK302/304-306 Notes 2-17 17 Rev. H 12/06 ...
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... LNK302/304-306 2-18 18 Rev. H 12/06 Notes ...
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... Revision Notes C 1) Released fi nal data sheet Corrected Minimum On Time Added LNK302 Added lead-free ordering information Minor error corrections. 2) Renamed Feedback Pin Voltage parameter to Feedback Pin Voltage at Turnoff Threshold and removed condition Added SO-8C package. LNK302/304-306 ...
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... LNK302/304-306 For the latest updates, visit our website: www.powerint.com Power Integrations reserves the right to make changes to its products at any time to improve reliability or manufacturability. Power Integrations does not assume any liability arising from the use of any device or circuit described herein. POWER INTEGRATIONS MAKES NO WARRANTY HEREIN AND SPECIFICALLY DISCLAIMS ALL WARRANTIES INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND NON-INFRINGEMENT OF THIRD PARTY RIGHTS ...