aoz1977 Alpha & Omega Semiconductor, aoz1977 Datasheet
aoz1977
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aoz1977 Summary of contents
Page 1
... Low feedback voltage (500 mV) helps reduce power loss. The AOZ1977 features a sync function to allow for synchronization with an external clock or multiple AOZ1977 devices. The AOZ1977 is available in a standard SO-16 package and operates over the -40 °C to +85 °C temperature range. Typical Application PVIN ...
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... ISET 2 15 GATE COMP 3 14 GND DBRT OVP 5 12 AUTO DPWM 6 11 OSC VREF 7 10 SYNC ILIM 8 9 SOIC-16 (Top View) Pin Function pin. Use a voltage divider to set the boost regulator output www.aosmd.com AOZ1977 Environmental Green Product synchronization. Page ...
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... To minimize power consumption recommended that the total resistance for the divider is approximately 20 kΩ. PIN 10: VREF This is a 1.2 V voltage reference for all external bias. This reference voltage can be used for PIN 15: ISET and PIN 9: ILIM bias. www.aosmd.com AOZ1977 ) Page ...
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... PIN 16: FB This is the feedback input for boost controller. This pin should connect to a resistor that senses the LED current. The FB voltage will be regulated to ISET voltage to determine the desired LED current when LED current control NMOS switch is on. www.aosmd.com AOZ1977 Page ...
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... The value of -65 °C to +150 °C FR-4 board with 2 oz. Copper still air environment with °C. The value in any given application depends on the A user’s specific board design. www.aosmd.com AOZ1977 VIN Driver VDD LDO UVLO Driver GATE Driver DPWM ...
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... ILIM = 0.4 V (140 % of CS) DBRT = 5 V OVP = 1 0.5 V PWM duty cycle 0 99.9 % 100 kΩ to GND VREF kΩ to GND 1.188 VREF CS = 0.3 V 120 0.9 GATE = GATE = 2.0 www.aosmd.com AOZ1977 Typ. Max Units 7.3 V 6.5 500 mV 8 8.5 V 100 115 kHz 350 402 ...
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... Rev. 1.0 July 2011 PVIN = 110V Gate (10V/div) Inductor Current (0.5A/div) LX Voltage (100V/div) 5µs/div PVIN = 150V Gate (10V/div) Inductor Current (0.5A/div) LX Voltage (100V/div) 5µs/div www.aosmd.com AOZ1977 Gate (10V/div) Inductor Current (0.5A/div) LX Voltage (100V/div) Gate (10V/div) Inductor Current (0.5A/div) LX Voltage (100V/div) Page ...
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... Zoomed DBRT = 0.5% LED Voltage (50V/div) LED Current (0.2A/div) DBRT (2V/div) 2µs/div LED Voltage (50V/div) LED Current (100mA/div) VDD (5V/div) 20ms/div www.aosmd.com AOZ1977 LED Voltage (50V/div) LED Current (0.2A/div) DBRT (2V/div) LED Voltage (50V/div) LED Current (0.2A/div) DBRT (2V/div) Page ...
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... AOZ1977 LED Voltage (20V/div) Inductor Current (0.5A/div) Feedback Voltage (0.5V/div) 200µs/div LED Voltage (20V/div) Inductor Current (0.5A/div) 500µs/div DBRT Control Linearity (PVIN = 130V, VOUT = 195V) ...
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... Detailed Description The AOZ1977 is a boost DC/DC controller designed to power a series of LEDs by regulating the current into the LED string. The LED current information is provided to the system through the sense resistor RFB at the bottom of the LED string, between FB pin and GND pin. Protection Features ...
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... Electrolytic capacitors should work well with the appropriate voltage and ripple current rating not recommended to use Tantalum capacitors because Boost converters do exhibit high surge currents during startup which can cause tantalum capacitors to fail. www.aosmd.com AOZ1977 Vout Vin – Vin × × ...
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... COMP pin sets the pole-zero and is adequate for a stable 0.3V 0.55Ω = --------------- - = high-bandwidth control loop. 0.55A In the AOZ1977, FB pin and COMP pin are the inverting input and the output of internal transconductance error amplifier. A series R and C compensation network connected to COMP provides one pole and one zero. The pole is ------------------------------------------ - P2 2π ...
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... A GND copper layer covers the top layer to help shield the noise. For two-layer board essential that the GND plane under this switching node should be filled and uninterrupted. PWR GND S SGNL GND www.aosmd.com AOZ1977 Page ...
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... C 0.19 — 0.25 D 9.80 — 10.00 5.74 E1 3.80 3.90 4.00 2.87 e 1.27 TYP E 5.80 6.00 6.20 L 0.40 — 1.27 θ 0° — www.aosmd.com AOZ1977 Dimensions in inches Symbols Min. Nom. Max. A 0.053 0.063 0.069 A1 0.004 — 0.010 — A2 — 0.057 — b 0.013 — 0.020 C 0.007 — 0.010 D 0.386 — 0.394 E1 0.150 0.154 0.157 e 0 ...
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... W3 (Include flange distortion at outer edge) W1 (Measured at Hub) N (Hub Dia.) W2 (Measured at Hub Ø100.0 2.0 16.4 22.4 15.9~19.4 +2.0 ±2.0 ±0.5 MAX. -0 Components Tape Orientation in Pocket www.aosmd.com AOZ1977 FEEDING DIRECTION 8.00 2.0 0.3 REF. REF. REF. 6.6 1.5 3.5 ±0.1 ±0.1 ±0.05 ...
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... WLT Assembly Lot Code Year & Week Code 2. A critical component in any component of a life support, device, or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system affect its safety or effectiveness. www.aosmd.com AOZ1977 Page ...