RT8004 RICHTEK [Richtek Technology Corporation], RT8004 Datasheet
RT8004
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RT8004 Summary of contents
Page 1
... Synchronous Step-Down Regulator General Description The RT8004 is a high efficiency synchronous, step-down DC/DC converter. Its input voltage range is from 2.65V to 5.5V and provides an adjustable regulated output voltage from 0. while delivering output current. The internal power switch with 75mΩ on-resistance increases efficiency and eliminates the need for an external Schottky diode ...
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... EN/ GND 8 9 SOP-16 Typical Application Circuit PGOOD www.richtek.com 2 (TOP VIEW) PVDD LX LX PGND PGND LX LX PVDD RPG 100k VDD RT8004 PGOOD CTH RTH 1000pF 10k COMP R2 LX 240k FB R OCS 309k RT PVDD External Clock SYNC R SS 4.7M EN/SS PVDD C SS 470pF ...
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... SYNC please connect this pin to VDD or GND. Enable Control and Soft-Start Input. Forcing this pin below 0.5V shuts down the RT8004. In shutdown all functions are disabled EN/SS drawing < 1uA of supply current. A capacitor to ground from this pin sets the ramp time to full output current. ...
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... MOSFET’ s current limit is reached. Frequency Synchronization The internal oscillator of the RT8004 can be synchronized to an external clock connected to the SYNC pin. The frequency of the external clock can be in the range of 300kHz to 4MHz. For this application, the oscillator timing resistor should be chosen to correspond to a frequency that is about 20% lower than the synchronization frequency ...
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... R of the P-Channel and N-Channel power switches increases. The user should calculate DS(ON) the power dissipation when the RT8004 is used at 100% duty cycle with low input voltages to ensure that thermal limits are not exceeded. Slope Compensation and Inductor Peak Current Slope compensation provides stability in constant frequency architectures by preventing subharmonic oscillations at duty cycles greater than 50% ...
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... RT8004 Absolute Maximum Ratings Supply Input Voltage ---------------------------------------------------------------------------------------------- LX Pin Switch Voltage -------------------------------------------------------------------------------------------- Other I/O Pin Voltages ------------------------------------------------------------------------------------------- Power Dissipation 25° SOP-16 -------------------------------------------------------------------------------------------------------------- 1.25W TSSOP-16 ----------------------------------------------------------------------------------------------------------- 2.66W VQFN-16L 4x4 ----------------------------------------------------------------------------------------------------- 2.315W Package Thermal Resistance (Note 4) SOP-16, θ -------------------------------------------------------------------------------------------------------- 100°C/W JA TSSOP-16, θ ----------------------------------------------------------------------------------------------------- 47°C/W JA VQFN-16L 4x4, θ ------------------------------------------------------------------------------------------------ 54°C/W JA VQFN-16L 4x4, θ ...
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... NFET SW I LIM VDD Rising Hysteresis 25°C on 4-layers high effective thermal conductivity test board the expose pad for the QFN package. JC RT8004 Min Typ Max Units 0.8 1 1.2 MHz 0 MHz 0 MHz 45 75 110 mΩ 100 mΩ ...
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... RT8004 Typical Operating Characteristics Efficiency vs. Output Current 100 100 3. 60% 50 50% 40 40% 30 30% 20 20 2.5V, 1M Continuous Mode Operation OUT 500 1000 1500 Output Current (mA) Soft-Star Power 3.3V 2.5V IN OUT R = 0.83Ω LOAD V OUT (1V/Div ...
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... RT8004 Frequency vs 200 400 600 800 1000 (kΩ) RT Frequency vs. Temperature V = 3.3V IN -50 - Temperature (°C) Peak Current Limited vs. Input Voltage V = 2.5V OUT 3 3.5 4 4.5 Input Voltage (V) www.richtek.com ...
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... The RT resistor value can be determined by examining the frequency Although frequencies as high as 4MHz are possible, the minimum on-time of the RT8004 imposes a minimum limit on the operating duty cycle. The minimum on-time is typically 110ns. Therefore, the minimum duty cycle is equal to 100 x 110ns x f(Hz). ...
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... Soft-Start The EN/SS pin provides a means to shut down the RT8004 as well as a timer for soft-start. Pulling the EN/SS pin below 0.5V places the RT8004 in a low quiescent current shutdown state (IQ < 1μA). ...
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... In most applications, the RT8004 does not dissipate much 2 R heat due to its high efficiency. But, in applications where the RT8004 is running at high ambient temperature with 2 R low supply voltage and high duty cycles, such as in dropout, the heat dissipated may exceed the maximum junction temperature of the part. If the junction temperature reaches approximately 150° ...
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... As an example, consider the RT8004 in dropout at an input voltage of 3.3V, a load current of 3A and an ambient temperature of 70°C. From the typical performance graph of switch resistance, the R of the P-Channel switch DS(ON) at 70°C is approximately 97mΩ. Therefore, power dissipated by the part ...
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... RT8004 Outline Dimension J I Symbol www.richtek.com Dimensions In Millimeters Dimensions In Inches Min Max 9.804 10.008 3.810 3.988 1.346 1.753 0.330 0.508 1.194 1.346 0.178 0.254 0.102 0.254 5.791 6.198 0.406 1.270 16– Lead SOP Plastic Package ...
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... Max 0.850 1.200 0.000 0.150 0.800 1.050 0.190 0.300 4.900 5.100 0.65 6.200 6.600 4.300 4.500 0.450 0.750 2.000 3.000 2.000 3.000 RT8004 Min Max 0.033 0.047 0.000 0.006 0.031 0.041 0.007 0.012 0.193 0.201 0.026 0.244 0.260 0.169 0.177 ...
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... RT8004 Symbol Richtek Technology Corporation Headquarter 5F, No. 20, Taiyuen Street, Chupei City Hsinchu, Taiwan, R.O.C. Tel: (8863)5526789 Fax: (8863)5526611 www.richtek.com 16 SEE DETAIL Note : The configuration of the Pin #1 identifier is optional, but must be located within the zone indicated. ...