cat37tdi-t3 Catalyst Semiconductor, cat37tdi-t3 Datasheet
cat37tdi-t3
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cat37tdi-t3 Summary of contents
Page 1
... For Ordering Information details, see page 11. TYPICAL APPLICATION CIRCUIT VIN Figure 1. Driver for Four High-Brightness White LEDs © Catalyst Semiconductor, Inc. Characteristics subject to change without notice DESCRIPTION The CAT37 is a DC/DC step up converter that delivers a regulated output current. Operation at a constant switching frequency of 1 ...
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... CAT37 ORDERING INFORMATION Part Number Package CAT37TDI-T3 TSOT-23 5-lead CAT37TDI-GT3 TSOT-23 5-lead PIN CONFIGURATION TSOT-23 5-Lead Top View GND 1mm maximum height θ = 250ºC/W [free air] JA PIN DESCRIPTION Pin Number Name Function Switch pin. This is the drain of the internal power switch. For minimum EMI, ...
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... Efficiency Notes: (1) These are stress ratings only and functional operation is not implied. Exposure to absolute maximum ratings for prolonged time periods may affect device reliability. All voltages are with respect to ground. © Catalyst Semiconductor, Inc. Characteristics subject to change without notice (1) Rating Unit ...
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... TEMPERATURE [ºC] FB Pin Voltage vs. Temperature 4 LEDs at 15mA 4LEDs at 15mA VIN = 3.6V VIN = 3.6V - TEMPERATURE [ºC] LOAD = 20mA LOAD =20 mA LOAD = 3 LEDs VIN LOAD = 3 LEDs = 3.6V VIN = 3.6V - TEMPERATURE [ºC] © Catalyst Semiconductor, Inc. Characteristics subject to change without notice 100 100 100 ...
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... VOUT = 10V VOUT = 10V INPUT VOLTAGE [ & V Waveforms SW L OUT Enable Power-Up Waveforms © Catalyst Semiconductor, Inc. Characteristics subject to change without notice = 1µ 6.8µH, unless otherwise specified. OUT Efficiency vs. Temperature LOAD = 3 LEDs 76 = 3.6V VIN = 3. -50 ...
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... Logic Error Amp Current Sense Amp GND 2 Figure 2. CAT37 Block Diagram 6 the internal power switch ¯¯¯¯¯ pin or by pulling the FB pin C2 I LED 6kΩ 0.095V REF © Catalyst Semiconductor, Inc. Characteristics subject to change without notice is ...
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... The diode conducts current only when the power switch is turned off (typically less than one-third the time 0.4A or 0.5A diode will be sufficient for most designs. © Catalyst Semiconductor, Inc. Characteristics subject to change without notice Table 2: Schottky Diode Suppliers Part MBR0520 ...
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... PWM R1 0.1µF 6.3Ω Figure 4. Dimming with a Filtered PWM Signal 095 LED ( MIN ) . 0 095 INCR I LED ( INCREASE ) CAT37 FB R INCR R1 Logic 2N7002 6.3Ω Signal Figure 5. Dimming with a Logic Signal © Catalyst Semiconductor, Inc. Characteristics subject to change without notice ...
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... CAT37 4 SHDN GND 2 Four LEDs with PWM Dimming Control L1 6.8µH VIN 3V to 4.2V C1 1µF 5 VIN SW CAT37 4 SHDN GND 2 © Catalyst Semiconductor, Inc. Characteristics subject to change without notice Dimming 1µF 1 18k 15mA 6.34kΩ Dimming 1µF ...
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... Complies with JEDEC standard MO-193. Doc. No. MD-5005 Rev. T SYMBOL θ θ MIN NOM MAX 1.00 0.01 0.05 0.10 0.80 0.87 0.90 0.30 0.45 0.12 0.15 0.20 2.90 BSC 2.80 BSC 1.60 BSC 0.95 TYP 0.30 0.40 0.50 0.60 REF 0.25 BSC 0º 8º END VIEW © Catalyst Semiconductor, Inc. Characteristics subject to change without notice ...
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... Notes: (1) All packages are RoHS-compliant (Lead-free, Halogen-free). (2) The standard lead finish is NiPdAu. (3) The device used in the above example is a CAT37TDI-GT3 (TSOT-23, NiPdAu, Tape & Reel, 3,000/Reel). (4) For additional package and temperature options, please contact your nearest Catalyst Semiconductor Sales office. © ...
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... Update Pin Configuration Update Pin Description Update Block Diagram Update Package Outlines Add TSOT-23 in NiPdAu plated finish Add Example of Ordering Information 19-May-08 T Update Package Outline Drawing Add MD- to document number Doc. No. MD-5005 Rev RSET Characteristics subject to change without notice © Catalyst Semiconductor, Inc. ...
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... Catalyst Semiconductor products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the Catalyst Semiconductor product could create a situation where personal injury or death may occur. ...