ADP1621-EVALZ Analog Devices Inc, ADP1621-EVALZ Datasheet
ADP1621-EVALZ
Specifications of ADP1621-EVALZ
Related parts for ADP1621-EVALZ
ADP1621-EVALZ Summary of contents
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... MOSFETs), and can be chosen for various switching frequencies and input and output voltages. The ADP1621 supply input voltage range is 2 5.5 V, although higher input voltages are possible with the use of a small-signal Rev. A Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use ...
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... ADP1621 TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 General Description ......................................................................... 1 Typical Application Circuit ............................................................. 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 Absolute Maximum Ratings............................................................ 5 Thermal Resistance ...................................................................... 5 ESD Caution.................................................................................. 5 Simplified Block Diagram ............................................................... 6 Pin Configuration and Function Descriptions............................. 7 Typical Performance Characteristics ............................................. 8 Theory of Operation ...................................................................... 12 Control Loop............................................................................... 12 Current-Sense Configurations.................................................. 12 Current Limit .............................................................................. 13 Undervoltage Lockout ............................................................... 13 Shutdown ...
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... SYNC 110 180 190 1.1 1.2 SYNC SW ADP1621 Max Unit Cycles V V SHUNT V V SHUNT 5.7 V 6.0 V Ω Ω μA 10 μA 10 μA 2 1.227 V 1.233 V + ...
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... Guaranteed by design for thermal shutdown. When the thermal junction temperature of the ADP1621 reaches approximately 150°C, the ADP1621 goes into thermal shutdown and the GATE voltage is pulled low. When the junction temperature drops below about 140°C, the soft start sequence is initiated and the ADP1621 resumes normal operation ...
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... dependent on the o = 150 C), the maximum applications where high maximum power dissipation exists, ), and the junction- D,MAX attention to thermal dissipation issues in board design given JA required. ). D,MAX ESD CAUTION Rev Page ADP1621 θ Unit JA 200 °C/W 172 °C/W ...
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... SIMPLIFIED BLOCK DIAGRAM FB COMP FREQ CS PGND GND V REF SOFT START 1.215V ERROR (2048 CYCLES) AMPLIFIER OSC 1.4V SET OSC SLOPE COMP PWM COMPARATOR + + UVLO n Figure 3. ADP1621 Simplified Block Diagram Rev Page PIN 5.5V S GATE R GATE DRIVER IN SDSN 100kΩ 5.5V ADP1621 ...
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... Shutdown and Synchronization Input. Turn the ADP1621 on by driving SDSN high; turn it off by driving SDSN low. If SDSN is left floating or when the SDSN is pulled low, the ADP1621 goes into shutdown after 50 μs. If synchronization is needed, synchronize the switching frequency to an external clock by connecting the external clock to the SDSN pin. An internal 100 kΩ ...
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... ADP1621 TYPICAL PERFORMANCE CHARACTERISTICS 100 0.01 0.1 LOAD CURRENT (A) Figure 5. Efficiency vs. Load Current T = 25° 3. OUT LOAD = CH1 20mV CH2 2V M2µs Figure 6. Output Voltage Ripple of the Circuit Shown in Figure 1 1.21605 T = 25°C A 1.21600 1.21595 1.21590 1.21585 1.21580 1.21575 2.5 3.0 3 ...
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... Figure 15. Oscillator Frequency vs. Resistance 198 T = 25° 197 FREQ 196 195 194 193 192 191 150 2 Rev Page ADP1621 = 5V t PIN FROM GATE CAPACITANCE (nF) GATE 100 120 140 160 180 R (kΩ) FREQ = 100kΩ ...
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... ADP1621 250 30V 200 150 100 50 0 – LEAKAGE (nA) Figure 17. Temperature vs. CS Leakage 1.2113V AT 25° BIAS CURRENT IS MEASURED BY FORCING A CONSTANT 1.2113V OVER THE TEMPERATURE RANGE –4 –8 –12 –16 – TEMPERATURE (°C) Figure 18. FB Bias Current vs. Temperature OSC 550kHz OSC ...
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... A CH2 3.8V Rev Page LOAD CURRENT FROM 0.2A TO 1.2A OUTPUT, AC-COUPLED OUT CH1 50mV M200µs A CH4 CH4 1AΩ 25° OUT NO LOAD AT V OUT CH1 = V , AC-COUPLED OUT CH2 = V FROM CH1 50mV CH2 2V M400µs A CH2 with No Load ADP1621 = 25° 700V 3.8V ...
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... MHz, and it can be synchronized to an external clock by connecting the SDSN pin to the clock. The input supply current to the ADP1621 is less than 3 mA during normal operation and less than 10 μA during shutdown. The ADP1621 can drive large external MOSFETs, allowing it to support load currents in excess ...
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... INTERNAL SHUNT REGULATORS The IN and PIN pins each have an internal shunt regulator that allows the ADP1621 to operate over a wide input voltage range. The shunt regulators limit the voltages at IN and PIN to about 5.5 V, allowing the use of logic-level MOSFETs independent of the input and/or output voltage ...
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... ADP1621 APPLICATION INFORMATION: BOOST CONVERTER In this section, an analysis of a boost converter is presented, along with guidelines for component selection. A typical boost- converter application circuit is shown in Figure 1. DUTY CYCLE To determine the worst-case inductor current ripple, output voltage ripple, and slope-compensation factor first necessary to determine the system duty cycle ...
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... ADP1621 and maintain the input voltage at a steady value during switching transitions. The bypass capacitor is typically a 0.1 μF or greater ceramic capacitor and should be placed as close as possible to the IN and PIN pins of the ADP1621. Capacitors C3 and C4 in Figure 1 represent the bypass capacitors. OUTPUT CAPACITOR SELECTION The output capacitor maintains the output voltage and supplies current to the load while the external MOSFET is on ...
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... Choose the MOSFET based on the following: threshold voltage ( resistance (R T maximum voltage and current ratings, and gate charge. The minimum operating voltage of the ADP1621 is 2.9 V. Choose a MOSFET with a V that is at least 0.3 V less than the T minimum input supply voltage at PIN used in the application. ...
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... For low ESR output capacitors, such as ceramic capacitors, C2 (26) is small, generally in the range 400 pF. Because of the parasitic inductance, resistance, and capacitance of the PCB layout, the R observing the load transient response of the ADP1621 to establish a (27) stable operating system and achieve optimal transient performance. For most applications the switching ...
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... for an incremental decrease in D. This behavior results L, “soft” current limit for the ADP1621. Use values close as possible to the calculated limit derived from Equation 34. If high-precision current limiting is required, consider inserting a fuse in series with the inductor. Also, keep in mind that the current limit is a function of both ADP1621 parameters and off-chip components, the values of which vary from part to part and with temperature ...
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... Given the minimum on time of the ADP1621, pulse-skipping modulation is also a requirement to maintain output voltage regulation with light loads. During the short switching periods of pulse-skipping modulation, the MOSFET is turned on for the RECOMMENDED COMPONENT MANUFACTURERS Table 5. Vendor AVX Corporation Central Semiconductor Corp. Coilcraft, Inc. ...
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... CS to PGND is minimized. • Place the compensation components as close as possible to COMP GND D1 M1 GATE GND ADP1621 SDSN R REMOTE OUTPUT FREQ VIAS TO GND PLANE VIAS TO 2ND LAYER Figure 32. PCB Layout of the Circuit Shown in Figure 33 (2-layer PCB) Rev Page for optimum output voltage OUT C OUT1 ...
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... The power dissipation in the winding resistance of the power stage inductor. (38) is the input power to the • The supply current to the ADP1621 IC, which includes the quiescent current and the gate driver charging current. The power dissipation due to gate charging loss is approximated by where P the PIN pin, Q (39) the converter switching frequency ...
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... ADP1621 EXAMPLES OF APPLICATION CIRCUITS STANDARD BOOST CONVERTER— DESIGN EXAMPLE The example covered here is for the ADP1621 configured as a standard boost converter, as shown in Figure 33, where lossless current sensing is employed. The design parameters are V 3 and a maximum load current OUT To begin this design, a switching frequency of 600 kHz is chosen (by setting kΩ ...
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... BOOTSTRAPPED BOOST CONVERTER The inputs of the ADP1621 can be driven from the step-up converter output voltage to improve efficiency for low input voltages. For low input voltages, bootstrapped operation improves efficiency with heavy loads by increasing the available gate drive voltage, thus reducing the on resistance of the MOSFET. However, ...
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... D2 = SIGNAL DIODE Figure 34. Bootstrapped Application Circuit for 3. 10µ 1.5kΩ 0.1µF 10V PIN 88.7kΩ 200Ω CS ADP1621 10kΩ SDSN M1 GATE COMP PGND R COMP FREQ FB 51.5kΩ GND C R COMP FREQ 330pF 31.6kΩ 1% AGND M1 = IRF7470 D1 = VISHAY SSC53L D2 SIGNAL DIODE Figure 35 ...
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... Figure 37. High Input Voltage and High Output Voltage Converter Rev Page 30V OUT OUT1 OUT2 OUT3 1µF 4.7µF 330µF 1% 50V 100V 50V × 47µF 6.3V × 30V OUT OUT1 OUT2 OUT3 1µF 4.7µF 330µF 1% 50V 100V 50V × 22µF 16V ×2 ADP1621 ...
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... OSC C1 = MURATA GRM32ER61C226K C = MURATA GRM31CR72A105K OUT1 C = MURATA GRM55ER71H475K OUT2 C = RUBYCON 63ZL220M10x23 OUT3 V = 12V 649Ω 15µ 10V IN PIN 324kΩ FB ADP1621 10.2kΩ SDSN M1 GATE COMP 442Ω 0.01Ω COMP FREQ PGND 2MΩ GND C R COMP FREQ 18pF 34.8Ω ...
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... C well as to supply current to the load. LOW VOLTAGE POWER-INPUT CIRCUIT The ADP1621 can be configured to run from a low voltage (as low power input. The power source generally needs to have a high current capability, such as a fuel cell. Figure 40 illustrates such an application, where the voltage of the power ...
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... Two methods for dimming the brightness of the LEDs are shown in Figure 41 and Figure 42. In Figure 41, a PWM signal is fed to the SDSN pin to turn the ADP1621 controller on and off result, the LED current is turned on and off, and the average LED current is dependent on the PWM duty cycle. The advantage of this method is that no current flows through the LEDs during the PWM off cycle ...
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... R LEDS S 800Ω 8Ω 3mΩ C1 1/4W 2.2µF 25V V = 10V TO 16V IN L1 33µH D1 100V V OUT C 150mA OUT 1µF 100V M1 ×3 100V 20 LEDS PWM = 10kΩ 22.9kΩ 10kΩ 8Ω 0.1µF 2.2µF 3m 1/4W 6.3V 25V ADP1621 ...
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... ADP1621 RELATED PARTS Table 6. Part Number Description ADP1610 Current-mode PWM step-up controller ADP1611 Current-mode PWM step-up controller Comments Maximum output = 12 V; PWM frequency = 700 kHz or 1.2 MHz; integrated 1.2 A, 0.2 Ω MOSFET power switch Maximum output = 20 V; PWM frequency = 700 kHz or 1.2 MHz; ...
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... Figure 43. 10-Lead Mini Small Outline Package [MSOP] (RM-10) Dimensions shown in millimeters Package Description 10-Lead Mini Small Outline Package [MSOP] 10-Lead Mini Small Outline Package [MSOP] Evaluation Board Rev Page 0.80 8° 0.60 0° 0.40 Package Ordering Option Quantity RM-10 50 RM-10 1,000 1 ADP1621 Branding L3M L3M ...
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... ADP1621 NOTES ©2006 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D06090-0-12/06(A) Rev Page ...