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AiT Semiconductor Inc. A7632 www.ait-ic.com DC-DC CONVERTER (BOOST) 2A 28V 1.2MHz CURRENT MODE STEP-UP CONVERTER REV2.0 - MAR 2017 RELEASED – MAY 2022 UPDATED - - 1 - DESCRIPTION FEATURES The A7632 is a constant frequency, current mode step-up converter intended for small, low power applications. The A7632 switches at 1.2MHz and allows the use of tiny, low cost capacitors and inductors 2mm or less in height. Internal soft-start results in small inrush current and extends battery life. The A7632 includes under-voltage lockout, current limiting, and thermal overload protection to prevent damage in the event of an output overload. The A7632 is available in SOT-26 package.

ORDERING INFORMATION

SPQ: 3,000pcs/Reel A7632E6R A7632E6VR Note V: Halogen free Package R: Tape & Reel AiT provides all RoHS products External Inductor & Diodes AiT Semiconductor Inductor: WSI04020E-4R7M Diode: SM140A  2.5V to 24V Input Voltage  Up to 28V Output Voltage  Accurate reference: 0.6V  Integrated 80mΩ power MOSFET  1.2MHz switching frequency  Internal 3A switch current Limit  Internal compensation  Thermal shutdown  Available in SOT-26 Package APPLICATION  ABS Set-Top Boxed  DVB-S/S2 TYPICAL APPLICATION A7632 + WSI04020E-4R7M + SM140A A7632 + WSI04020E-4R7M + SM140A

AiT Semiconductor Inc. A7632 www.ait-ic.com DC-DC CONVERTER (BOOST) 2A 28V 1.2MHz CURRENT MODE STEP-UP CONVERTER REV2.0 - MAR 2017 RELEASED – MAY 2022 UPDATED - - 2 - PIN DESCRIPTION Top View Pin # Symbol Function 1 SW Power Switch Output. SW is the drain of the internal MOSFET switch. Connect the power inductor and output rectifier to SW. SW can swing between GND and 28V. 2 GND Ground. 3 FB Feedback input. The FB voltage is 0.6V. Connect a resistor divider to FB. 4 EN Regulator On/Off control input. A high input at EN turns on the converter, and a low input turns it off. When not used, connect EN to the input supply for automatic startup. 5 VIN Power supply. Must be locally bypassed.

6 NC No connection

AiT Semiconductor Inc. A7632 www.ait-ic.com DC-DC CONVERTER (BOOST) 2A 28V 1.2MHz CURRENT MODE STEP-UP CONVERTER REV2.0 - MAR 2017 RELEASED – MAY 2022 UPDATED - - 3 - ABSOLUTE MAXIMUM RATINGS TA = 25°C Parameter Symbol Value Unit IN, EN Pin Voltage -0.3 ~ 26 V SW Pin Voltage -0.3 ~ 26 V All Other Pin Voltage -0.3 ~ 6 V Junction Temperature T J 150 °C Ambient Temperature T A -40 ~ 85 °C Power Dissipation SOT-26 600 mW Thermal Resistance θ JA 250 °C/W Thermal Resistance θ JC 130 °C/W Storage Temperature T S -65 ~ 150 °C Lead Temperature & Time 260, 10 °C,Sec Stress beyond above listed “Absolut e Maximum Ratings” may lead permanent damage to the device. These are stress ratings only a nd operations of the device at these or any other conditions beyond those indicated in the operati onal sections of the specificat ions are not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. RECOMMENDED OPERATING CONDITIONS Parameter Symbol Value Units Input Voltage Range 2.5 to 24 V Output Voltage Range V IN to 28 V Operating Junction Temperature T J -40 to 125 °C

AiT Semiconductor Inc. A7632 www.ait-ic.com DC-DC CONVERTER (BOOST) 2A 28V 1.2MHz CURRENT MODE STEP-UP CONVERTER REV2.0 - MAR 2017 RELEASED – MAY 2022 UPDATED - - 4 -

ELECTRICAL CHARACTERISTICS

Test Conditions: VIN=5V and VOUT=12V, L= WSI4020E-4R7M = 4.7uH. TA=25°C, unless otherwise noted Parameter Symbol Conditions Min. Typ. Max. Unit Operating Input Voltage V IN 2.5 - 24 V Under voltage lockout threshold VIN_UVLO VIN rising - 2.4 - V VIN_UVLO hysteresis - 50 - mV Feedback Voltage V FB 588 600 612 mV FB Input Bias Current I FB V FB=0.6V -50 -10 - nA SW Leakage I SW_LKG V SW=20V - - 1 μA Quiescent Current I Q VFB=0.8V, No Switch - 0.25 0.5 mA VEN=0V - 0.1 1 μA Oscillator Frequency F SW - 1.2 - MHz Soft-start time T SS 1 . 5 m S Maximum Duty Cycle D MAX - 8 5 - % Minimum ON time T ON(MIN) - 120 - ns EN pin logic high threshold VEN_H 1.0 - - V EN pin logic low threshold VEN_L - - 0.5 V SW On-Resistance R DS_ON - 200 - mΩ Current Limit I LIMIT V IN=5V, Duty Cycle = 50% - 3 - A Thermal Shutdown T SD - 160 - °C

AiT Semiconductor Inc. A7632 www.ait-ic.com DC-DC CONVERTER (BOOST) 2A 28V 1.2MHz CURRENT MODE STEP-UP CONVERTER REV2.0 - MAR 2017 RELEASED – MAY 2022 UPDATED - - 5 - TYPICAL PERFORMANCE CHARACTERISTICS 1. Efficiency vs. Iout (VOUT=5V) 2. Efficiency vs. Iout (VOUT=9V) 3. Efficiency vs. Iout (VOUT=12V) 4. Efficiency vs. Iout (VOUT=18V) 5. Efficiency vs. Iout (VOUT=24V) 6. Efficiency vs. Iout (VOUT=28V)

AiT Semiconductor Inc. A7632 www.ait-ic.com DC-DC CONVERTER (BOOST) 2A 28V 1.2MHz CURRENT MODE STEP-UP CONVERTER REV2.0 - MAR 2017 RELEASED – MAY 2022 UPDATED - - 6 - 7. Load Regulation (VOUT=5V) 8. Load Regulation (VOUT=9V) 9. Load Regulation (VOUT=12V) 10. Load Regulation (VOUT=18V) 11. Load Regulation (VOUT=24V) 12. Load Regulation (VOUT=28V)

AiT Semiconductor Inc. A7632 www.ait-ic.com DC-DC CONVERTER (BOOST) 2A 28V 1.2MHz CURRENT MODE STEP-UP CONVERTER REV2.0 - MAR 2017 RELEASED – MAY 2022 UPDATED - - 7 - 13. VFB vs. Temperature 14. IQ (No Switching) 15. Enable Response (VIN=5V, VOUT=12V, IOUT=800mA, EN=0→3V) 16. Enable Response (VIN=5V, VOUT=12V, IOUT=800mA, EN=3→0V) CH1: EN, CH2: VOUT, CH2: VSW, CH4: IL CH1: EN, CH2: VOUT, CH2: VSW, CH4: IL

AiT Semiconductor Inc. A7632 www.ait-ic.com DC-DC CONVERTER (BOOST) 2A 28V 1.2MHz CURRENT MODE STEP-UP CONVERTER REV2.0 - MAR 2017 RELEASED – MAY 2022 UPDATED - - 8 - BLOCK DIAGRAM

AiT Semiconductor Inc. A7632 www.ait-ic.com DC-DC CONVERTER (BOOST) 2A 28V 1.2MHz CURRENT MODE STEP-UP CONVERTER REV2.0 - MAR 2017 RELEASED – MAY 2022 UPDATED - - 9 - DETAILED INFORMATION The A7632 uses a fixed frequency, peak current mode boost regulator architecture to regulate voltage at the feedback pin. The operation of the A7632 can be understood by referring to the block diagram. At the start of each oscillator cycle the MOSFET is turned on through the contr ol circuitry. To prevent sub-harmonic oscillations at duty cycles gr eater than 50%, a stabilizing ram p is added to the output of the current sense amplifier and the result is fed into the negative input of the PWM comparator. When this voltage equals the output voltage of the error amplifier the power MOSFET is turne d off. The voltage at the output of the error amplifier is an amplified version of the difference between the 0.6V band gap reference voltage and the feedback voltage. In this way the peak current level keeps the output in regulation. If the feedback voltage starts to drop, the output of the error amplifier increases. Th ese results in more current to flow through the power MOSFET, thus increasing the power delivered to the output . The A7632 has internal soft start to limit the amount of input current at startup and to also limit the am ount of overshoot on the output. The A7632 includes a number of protection features including under-voltag e lockout, current limiting, thermal shutdown protection and output over voltage protection. Output voltage protection works when FB short to the GND.

APPLICATION INFORMATION

Setting the Output Voltage The internal reference V REF is 0.6V (Typical). The output voltage is divided by a resistor divider, R1 and R2 to the FB pin. The output voltage is given by VOUT = VREF X    R2 R11 Inductor Selection The recommended WSI04020E-4R7M values of inductor are 4.7 to 22 μH. Suggest AiT Semi’s WSI04020E-4R7M, small size and better efficiency are the major concerns for portable device, such as A7632 used for mobile phone. The inductor WSI04020E-4R7M have l ow core loss at 1.2MHz and low DCR for better efficiency. To avoid inductor saturation current rating should be considered. Capacitor Selection Input and output ceramic capacitors of 22μF are recommended for A7632 applications. For better voltage filtering, ceramic capacitors with low ESR are recommended. X5R and X7R types are suitable because of their wider voltage and temperature ranges.

AiT Semiconductor Inc. A7632 www.ait-ic.com DC-DC CONVERTER (BOOST) 2A 28V 1.2MHz CURRENT MODE STEP-UP CONVERTER REV2.0 - MAR 2017 RELEASED – MAY 2022 UPDATED - - 10 - Diode Selection AiT Semi’s Schottky diode SM140A is a good choice for A7632 bec ause of its low forward voltage drop and fast reverses recovery. Using Schottky diode can get better efficiency. The high speed rectification SM140A is also a good characteristic of Schottky diode for high switching frequency. Current rating of the diode must meet the root mean square of the peak current and output average current multiplication as following: ID(RMS) ≈ PEAKOUT Ix I The diode’s reverse breakdown voltage should be larger than the output voltage. Layout Consideration When laying out the printed circuit board, the following checking should be used to ensure proper operation of the A7632. Check the following in your layout: 1. The power traces, consisting of the GND trace, the SW trace and the V IN, trace should be kept short, direct and wide. 2. Does the (+) plates of Cin connect to Vin as closely as possible. This capacitor provides the AC current to the internal power MOSFETs. 3. Keep the switching node SW away from the sensitive VOUT node. 4. Keep the (-) plates of Cin and Cout as close as possible

AiT Semiconductor Inc. A7632 www.ait-ic.com DC-DC CONVERTER (BOOST) 2A 28V 1.2MHz CURRENT MODE STEP-UP CONVERTER REV2.0 - MAR 2017 RELEASED – MAY 2022 UPDATED - - 11 -

PACKAGE INFORMATION

Dimension in SOT-26 (Unit: mm) Symbol Millimeters Min Nom Max A 1.100 1.2 1.400 A1 0.000 - 0.100 A2 1.000 1.100 1.300 b 0.200 0.400 0.500 c 0.100 0.15 0.250 D 2.700 2.900 3.100 E 1.500 1.600 1.800 E1 2.500 2.800 3.100 e 0.950 BSC e1 1.700 1.900 2.100 L 0.300 - 0.600 θ 0  - 8 

AiT Semiconductor Inc. A7632 www.ait-ic.com DC-DC CONVERTER (BOOST) 2A 28V 1.2MHz CURRENT MODE STEP-UP CONVERTER REV2.0 - MAR 2017 RELEASED – MAY 2022 UPDATED - - 12 - IMPORTANT NOTICE AiT Semiconductor Inc. (AiT) reserves the right to make changes to any its product, specifications, to discontinue any integrated circu it product or service without n otice, and advises its customers to obtain the latest version of relevant information to verify, before placin g orders, that the information being relied on is current. AiT Semiconductor Inc.'s integrat ed circuit products are not de signed, intended, authorized, or warranted to be suitable for use in life support applications, devices or sy stems or other critical applications. Use of AiT products in such applications is understood to be fully at the risk of the customer. As used herein may involve potential risks of death, personal injury, or servere property, or environmental damage. In order to minimize risks associated with the custom er's applications, the customer should provide adequate design and operating safeguards. AiT Semiconductor Inc. assumes to no liability to customer prod uct design or application support. AiT warrants the performance of its products of the specifications applicable at the time of sale.