A7240MP8R

A7240 AITSEMI | Alldatasheet

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AiT Semiconductor Inc. www.ait-ic.com A7240 DC-DC CONVERTER/ BUCK (STEP-DOWN) 4A, 16V HIGH EFFICIENCY SYNCHRONOUS REV2.0 - MAY 2016 RELEASED, MAY 2021 UPDATED - - 1 - DESCRIPTION FEATURES The A7240 is a wide input range, high -efficiency, DC-to-DC step-down switching regulator, capable of delivering up to 4A of output current. Current mode PWM control allows the use of small external components, such as ceramic input a nd output caps, as well as small inductors, while still providing low output ripples. On top of the integrated internal synchronous rectifier that eliminates external Schottky diode, A7240 also employs a proprietary control scheme that switches the device into a power save mode during light load, thereby extending the range of high efficiency operation. Therefore, A7240 is a much superior solution in comparison to other competitions in terms of efficiency and cost. Overall, A7240 is a highly efficient an d ro bust solution for DC-DC step -down applications that requires wide input ranges. The A7240 is available in PSOP8 package.

ORDERING INFORMATION

SPQ: 2,500pcs/Reel MP8 A7240MP8R A7240MP8VR Note V: Halogen free Package R: Tape & Reel AiT provides all RoHS products ⚫ Wide Input Operating Range from 4.2V to 16V ⚫ High Efficiency: Up to 95% at Light Load ⚫ Capable of Delivering 4A ⚫ No external Schottky Diode Needed ⚫ Inductor Short Circuit Protection ⚫ Current Mode Control ⚫ 0.923V Reference for Low Output Voltages ⚫ Logic Control Shutdown ⚫ Thermal Shutdown and UVLO ⚫ Available in PSOP8 package APPLICATION ⚫ LCD TVs ⚫ Notebook computers ⚫ FPGA power supplies ⚫ LED drivers TYPICAL APPLICATION

AiT Semiconductor Inc. www.ait-ic.com A7240 DC-DC CONVERTER/ BUCK (STEP-DOWN) 4A, 16V HIGH EFFICIENCY SYNCHRONOUS REV2.0 - MAY 2016 RELEASED, MAY 2021 UPDATED - - 2 - PIN DESCRIPTION Top View Pin # Symbol Description 1 BST High side power transistor gate drive boost input. 2 VIN Power input. Bypass with a 10uF~22uF ceramic capacitor to GND. 3 SW Power switching node to connect inductor.

4 GND Ground

5 FB Feedback input with reference voltage set to 0.923V.

6 NC No connection

7 EN Enable input. Set this pin to high level to enable the part, low level to disable.

8 NC No connection

AiT Semiconductor Inc. www.ait-ic.com A7240 DC-DC CONVERTER/ BUCK (STEP-DOWN) 4A, 16V HIGH EFFICIENCY SYNCHRONOUS REV2.0 - MAY 2016 RELEASED, MAY 2021 UPDATED - - 3 - ABSOLUTE MAXIMUM RATINGS Input Voltage -0.3V ~ 17V SW.EN Voltage -0.3V ~ VIN +0.3V BST Voltage -0.3V ~ SW +6V FB Voltage -0.3V ~ 6V SW to Ground Current Internally Limited TA, Ambient Temperature -40°C ~ 85℃ TS, Storage Temperature -55°C ~ 150℃ Stress beyond above listed “Absolute Maximum Ratings” may lead permanent damage to the device. These are stress ratings only and operations of the device at these or any other conditions beyond those indicated in the operational sections of the specifications are not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.

ELECTRICAL CHARACTERISTICS

VIN=12V, VOUT=5V, TA=25℃, unless otherwise stated Parameter Conditions Min Typ Max Unit Input Voltage Range 4.2 - 16 V UVLO Threshold - 4.1 - V Supply Current in Operation VEN = 2.0V, VFB = 1.1V - 0.5 - mA Supply Current in Shutdown VEN = 0V or VEN = GND - 5 10 uA Regulated Feedback Voltage 4.2V≤VIN ≤16V 0.904 0.923 0.942 V High-side Switch On Resistance VBST-SW = 5V - 120 - mΩ Low-side Switch On Resistance VIN = 5V - 60 - mΩ High-side Switch Leakage Current VEN = 0V, VSW = 0V - 0 10 uA Upper Switch Current Limit Minimum Duty Cycle - 6 - A Oscillation Frequency - 500 - kHz Maximum Duty Cycle VFB = 0.8V - 92 - % Minimum On Time - 100 - ns EN Input Voltage “H” 1.5 - - V EN Input Voltage “L” - - 0.6 V Thermal Shutdown - 160 - °C

AiT Semiconductor Inc. www.ait-ic.com A7240 DC-DC CONVERTER/ BUCK (STEP-DOWN) 4A, 16V HIGH EFFICIENCY SYNCHRONOUS REV2.0 - MAY 2016 RELEASED, MAY 2021 UPDATED - - 4 - TYPICAL PERFORMANCE CHARACTERISTICS L=4.7uH, CIN=22uF, COUT=22uF, TA=25°C, unless otherwise stated

AiT Semiconductor Inc. www.ait-ic.com A7240 DC-DC CONVERTER/ BUCK (STEP-DOWN) 4A, 16V HIGH EFFICIENCY SYNCHRONOUS REV2.0 - MAY 2016 RELEASED, MAY 2021 UPDATED - - 5 - 7. VOUT vs. VIN, IOUT=0 8. VOUT vs. VIN, IOUT=1A

AiT Semiconductor Inc. www.ait-ic.com A7240 DC-DC CONVERTER/ BUCK (STEP-DOWN) 4A, 16V HIGH EFFICIENCY SYNCHRONOUS REV2.0 - MAY 2016 RELEASED, MAY 2021 UPDATED - - 6 - DETAILED INFORMATION FUNCTIONAL DECRIPTIONS Loop Operation The A7240 is a wide input range, high -efficiency, DC -to-DC step -down switching regulator, capable of delivering up to 4A of output current, integrated with a 120/60m Ω synchronous MOSFET pair, eliminating the need for external diode. It uses a PWM current -mode control scheme. An error amplifier integrates error between the FB signal and the internal reference voltage. The output of the integrator is then compared to the sum of a current-sense signal and the slope compensation ramp. This operation generates a PWM signal that modulates the duty cycle of the power MOSFETs to achieve regulation for output voltage. Current Limit There is a cycle-by-cycle current limit on t he high-side MOSFET of 6A (typ). When the current flowing out of SW exceeds this limit, the high -side MOSFET turns off and the synchronous rectifier turns on. Unlike the traditional method of current limiting by limiting the voltage at the compensation pin , which usually has large variation due to duty cycle variance, this type of peak current limiting scheme provides a relatively more accurate limit for output current, thereby lowering the requirements for system design. Light Load Operation Traditionally, a fixed constant frequency PWM DC-DC regulator always switches even when the output load is small. When energy is shuffling back and forth through the power MOSFETs, power is lost due to the finite RDSONs of the MOSFETs and parasitic capacitances. At li ght load, this loss is prominent and efficiency is therefore very low. A7240 employs a proprietary control scheme that improves efficiency in this situation by enabling the device into a power save mode during light load, thereby extending the range of hi gh efficiency operation.

AiT Semiconductor Inc. www.ait-ic.com A7240 DC-DC CONVERTER/ BUCK (STEP-DOWN) 4A, 16V HIGH EFFICIENCY SYNCHRONOUS REV2.0 - MAY 2016 RELEASED, MAY 2021 UPDATED - - 7 - PCB LAYOUT RECOMMENDATION The device’s performance and stability are dramatically affected by PCB layout. It is recommended to follow these general guidelines shown as below: 1. Place the input capacitors and output capacit ors as close to the device as possible. The traces which connect to these capacitors should be as short and wide as possible to minimize parasitic inductance and resistance. 2. Place feedback resistors close to the FB pin. 3. Keep the sensitive signal (FB) away from the switching signal (SW). 4. The exposed pad of the package should be soldered to an equivalent area of metal on the PCB. This area should connect to the GND plane and have multiple via connections to the back of the PCB as well as connections to intermediate PCB layers. The GND plane area connecting to the exposed pad should be maximized to improve thermal performance. 5. Multi-layer PCB design is recommended.

AiT Semiconductor Inc. www.ait-ic.com A7240 DC-DC CONVERTER/ BUCK (STEP-DOWN) 4A, 16V HIGH EFFICIENCY SYNCHRONOUS REV2.0 - MAY 2016 RELEASED, MAY 2021 UPDATED - - 8 -

PACKAGE INFORMATION

Dimension in PSOP8 Package (Unit: mm) Symbol Min Max A 1.35 1.75 A1 0.00 0.15 A2 1.25 1.65 A3 0.50 0.70 b 0.38 0.51 b1 0.37 0.47 c 0.17 0.25 c1 0.17 0.23 D 4.80 5.00 D1 3.10 3.50 E 5.80 6.20 E1 3.80 4.00 E2 2.20 2.60 e 1.27 BSC L 0.45 0.80 L1 1.04 REF L2 0.25 BSC R 0.07 - R1 0.07 - h 0.30 0.50 θ 0° 8° θ1 15° 19° θ2 11° 15° θ3 15° 19° θ4 11° 15°

AiT Semiconductor Inc. www.ait-ic.com A7240 DC-DC CONVERTER/ BUCK (STEP-DOWN) 4A, 16V HIGH EFFICIENCY SYNCHRONOUS REV2.0 - MAY 2016 RELEASED, MAY 2021 UPDATED - - 9 - IMPORTANT NOTICE AiT Semiconductor Inc. (AiT) reserves the right to make changes to any its product, specifications, to discontinue any integrated circuit product or service without notice, and advises its customers to obtain the latest version of relevant information to verify, before placing orders, that the information being relied on is current. AiT Semiconductor Inc. 's integrated circuit products are not designed, intended, authorized, or warranted to be suitable for use in life support applications, devices or systems 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 customer's applications, the customer should provide adequate design and operating safeguards. AiT Semiconductor Inc . assumes to no liabil ity to customer product design or application support. AiT warrants the performance of its products of the specifications applicable at the time of sale.