A8515GLPTR-T Allegro Microsystems Inc, A8515GLPTR-T Datasheet
A8515GLPTR-T
Specifications of A8515GLPTR-T
Related parts for A8515GLPTR-T
A8515GLPTR-T Summary of contents
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Features and Benefits • Wide input voltage range • Maximum LED current of 120 mA • TSSOP-16 (LP) package; exposed pad offers best-in-class thermal performance • Typical LED accuracy of 0.5%, and 0.5% for LED-to-LED matching ...
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... A8515 Selection Guide Part Number A8515GLPTR-T 4000 pieces per 13-in. reel Absolute Maximum Ratings* Characteristic LEDx Pin OVP Pin VIN, VSENSE, GATE Pins SW Pin ¯ F ¯ ¯ A ¯ U ¯ ¯ L ¯ ¯ T ¯ Pin ISET, FSET, APWM Pins All other pins ...
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A8515 Terminal List Table Number Name 1 VDD Output of internal LDO; connect a 0.1 μF decoupling capacitor between this pin and GND. 2 PGND Power ground for internal NMOS device. This pin is used to sense an overvoltage condition; ...
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A8515 VIN FSET/SYNC COMP VSENSE GATE PWM APWM Internal V ISET Wide Input Voltage Range, High Efficiency Functional Block Diagram VDD Internal Regulator 1.235 V REF UVLO Ref Internal V CC AGND ∑ + Oscillator – + ...
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A8515 ELECTRICAL CHARACTERISTICS characterization over the full operating temperature range with T Characteristics Input Voltage Specifications Operating Input Voltage Range UVLO Start Threshold V UVLO Stop Threshold UVLO Hysteresis 3 V Input Currents Input Quiescent Current Input Sleep Supply Current ...
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A8515 ELECTRICAL CHARACTERISTICS and characterization over the full operating temperature range with T Characteristics Oscillator Frequency Oscillator Frequency FSET Pin Voltage FSET Frequency Range Synchronization Synchronized PWM Frequency Synchronization Input t PWSYNCOFF Minimum Off-Time Synchronization Input t PWSYNCON Minimum On-Time ...
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A8515 ELECTRICAL CHARACTERISTICS and characterization over the full operating temperature range with T Characteristics VSENSE Pin VSENSE Pin Sink Current VSENSE Trip Point V VSENSE 2X Trip V ¯ F ¯ ¯ A ¯¯ U ¯ ¯ L ¯ ¯ ...
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A8515 VIN Input Sleep Mode Current versus Ambient Temperature -50 -40 -30 -20 - 100 110 Temperature (°C) Switching ...
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A8515 ISET to LED Current Gain versus Ambient Temperature 1000 995 990 985 980 975 970 965 960 -50 -40 -30 -20 - 100 110 Temperature (°C) LED Current versus ...
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A8515 Wide Input Voltage Range, High Efficiency Fault Tolerant LED Driver Efficiency for Various LED Configurations LED 100 5.5 7.0 8.5 10.0 11.5 13.0 14.5 Input Voltage, V ...
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A8515 Enabling the IC The IC turns on when a logic high signal is applied on the PWM pin with a minimum duration of t PWMH and the input voltage present on the VIN pin is greater than the 4.35 ...
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A8515 The LED pin detection voltage thresholds are as follows: LED Pin Voltage LED Pin Status <170 mV Short-to-GND 150 mV Not used LED removed from operation 325 mV LED pin in use All unused pins should be connected with ...
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A8515 Soft start function During soft start the LEDx pins are set to sink (I boost switch current is reduced to the I inrush current generated by charging the output capacitors. When the converter senses that there is enough voltage ...
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A8515 The basic requirement of the sync signal is 150 ns minimum on- time and 150 ns minimum off time, as indicated by the specifica- tions for t and t . Figure 9 shows the timing PWSYNCON PWSYNCOFF for a ...
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A8515 V OUT COMP C2 PWM LED t Figure 11A. Typical PWM diagram showing V well as the PWM signal. PWM dimming frequency is 500 Hz at 50% duty cycle; shows V (ch1, 10 V/div.), COMP ...
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A8515 APWM pin The APWM pin is used in conjunction with the ISET pin. This is a digital signal pin that internally adjusts the ISET current. The typical input signal frequency is between 20 kHz and 1 MHz. The duty ...
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A8515 appropriate value. Another consideration that also is important is the limitation of the user APWM signal duty cycle. In some cases it might be preferable to set the maximum ISET current to be 25% to 50% higher, thus allowing ...
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A8515 Figure 19 illustrates when the output of the A8515 is discon- nected from load during normal operation. The output voltage instantly increases up to OVP voltage level and then the boost stops switching to prevent damage to the IC. ...
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A8515 Boost switch overcurrent protection The boost switch is protected with pulse-by-pulse current limiting set at a minimum of 3.0 A. There is also a secondary current limit that is sensed on the boost switch. When detected this current C1 ...
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A8515 Input overcurrent protection and disconnect switch The primary function of the input disconnect switch is to protect the system and the device from catastrophic input currents during a fault condition. The external circuit implementing the discon- nect is shown ...
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A8515 Input UVLO When V and V rise above the V IN SENSE A8515 is enabled. A8515 is disabled when V t threshold for more than 50 μs. This small delay is used UVLOfall to avoid shutting down because of ...
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A8515 Fault Mode Table Fault Name Type Active Primary switch overcurrent protection Auto-restart Always (pulse-by-pulse current limit) Secondary switch Latched Always current limit Input disconnect Latched Always current limit Secondary OVP Latched Always LED Pin Short Auto-restart Startup Protection Normal ...
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A8515 Fault Mode Table (continued) Fault Name Type Active FSET Short Protection Auto-restart Always Overvoltage Auto-restart Always Protection lED Short Protection Auto-restart Always Overtemperature Auto-restart Always Protection VIN UVLO Auto-restart Always Wide Input Voltage Range, High Efficiency Fault Tolerant LED ...
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A8515 Design Example This section provides a method for selecting component values when designing an application using the A8515. The resulting design is diagramed in figure 30. Assumptions: For the purposes of this example, the following are given as the ...
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A8515 Step 4a Determining the duty cycle, calculated as follows: (min – = D(max OUT(OVP 0.9 1 – 77% 38.38 + 0.4 Step 4b Determining the maximum and minimum ...
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A8515 variation on the output (V ) during PWM dimming must COUT be less than 250 mV, so that no audible hum can be heard. The capacitance can be calculated as follows: 1 – D(min OUT ...
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A8515 4.7 μ kΩ R ISET 8.25 kΩ Figure 30. The schematic diagram showing calculated values from the design example above Wide Input Voltage Range, High Efficiency 0.03 Ω ...
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A8515 Typical Application Circuits 4.7 μ kΩ R ISET 8.25 kΩ Figure 31. Typical application showing boost configuration, using current sensing and disconnect switch feature for an input ...
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A8515 Package LP, 16-Pin TSSOP with Exposed Thermal Pad 5.00±0. NOM 16X 0.10 C 0.30 0.19 0.65 BSC Copyright ©2010, Allegro MicroSystems, Inc. The products described here are manufactured under one or more U.S. ...