I.Product Introduction

XBL1663 in ESOP-8 package delivers up to 5A output current

XBLW XBL1663 is a monolithic integrated circuit designed for step-down DC/DC converters, featuring high conversion efficiency and constant switching frequency operation. The built-in power MOSFET enables 5A peak output current from a 4.5V–40V input supply, with excellent load and line regulation performance, greatly saving PCB space and cost.

XBL1663 can drive 5A high current with very few external components, making it an ideal choice for devices such as power meters, distributed power systems, battery chargers, pre-regulators for linear regulators, and LED drivers.

XBL1663 features thermal shutdown and current limit functions. Thermal shutdown prevents chip damage caused by excessive temperature, while current limit protects against overcurrent operation of the output switch.

II.Key Features

Wide input voltage range:4.5V to 40V, adapting to various power supply environments.

Fixed 300kHz switching frequency:Supports smaller filter components and improves space utilization.

Built-in switching MOSFET:150mΩ internal power MOSFET saves space and simplifies external circuit design.

High operating efficiency:Conversion efficiency up to 91%.

Low-power standby mode:Standby current 0.1μA, extending device operating time.

High duty cycle:Maximum duty cycle 100%.

Protection functions:Cycle-by-cycle overcurrent protection, thermal shutdown protection.

Enable pin control input:Controlled by logic level for easy integration.

Output load current:Maximum load 5A, adapting to different power requirements.

III.Applications

Power Meters

Distributed Power Systems

Battery Chargers

LED Drivers

IV.Pin Description

XBL1663 Pin Diagram

NC: Not connected.

VIN: Supply voltage. XBL1663 operates with adjustable voltage from 4.5V to 40V. Ci is required to prevent large voltage spikes at the input terminal.

EN: Enable pin. Device shuts down below 1.2V and operates at 1.35V or above.

NC: Not connected.

FB: Feedback, sets the output voltage. When the FB voltage is below 300mV, the frequency foldback comparator reduces the oscillator frequency to prevent loss of current mode control during short-circuit faults.

NC: Not connected.

GND: Ground, voltage reference for regulated output voltage. Special layout considerations are required to isolate this node from the D1 to C1 ground path to prevent inductive switching current spikes.

SW: Power switch output. It is the drain of the N-channel power MOSFET, supplying the output Lc filter.

V.Electrical Characteristics

Input supply voltage: 4.5V to 40V.

Quiescent current: 2.8mA to 3mA.

Oscillation frequency: 240kHz to 360kHz.

Switch current limit: 8A.

Maximum duty cycle: 100%.

Conversion efficiency: Up to 91%.

Absolute Maximum Ratings

VI.Typical Application Circuit

XBL1663 is a current-mode step-down regulator. The EA output voltage is proportional to the peak inductor current. At the beginning of the cycle, M1 is off. The EA output voltage is higher than the current sense amplifier output, the current comparator output is low, and the rising edge of the 300kHz CLK signal sets the RS flip-flop. Its output turns on M1, connecting the SW pin and inductor to the input supply. The current sense amplifier detects and amplifies the rising inductor current, adds slope compensation to the current sense amplifier output, and compares it with the error amplifier output at the PWM comparator. When the sum of the current sense amplifier output and the slope compensation signal exceeds the EA output voltage, the RS flip-flop resets and M1 turns off. The external Schottky rectifier diode (D1) conducts the inductor current. If the sum of the current sense amplifier output and the slope compensation signal does not exceed the EA output during the entire cycle, the falling edge of CLK resets the flip-flop. An FB pin voltage below 0.750V increases the EA output voltage. Since the EA output voltage is proportional to the peak inductor current, an increase in its voltage also increases the current delivered to the output.

VII.Ordering Information

I.Product Introduction

XBL1663 in ESOP-8 package delivers up to 5A output current

XBLW XBL1663 is a monolithic integrated circuit designed for step-down DC/DC converters, featuring high conversion efficiency and constant switching frequency operation. The built-in power MOSFET enables 5A peak output current from a 4.5V–40V input supply, with excellent load and line regulation performance, greatly saving PCB space and cost.

XBL1663 can drive 5A high current with very few external components, making it an ideal choice for devices such as power meters, distributed power systems, battery chargers, pre-regulators for linear regulators, and LED drivers.

XBL1663 features thermal shutdown and current limit functions. Thermal shutdown prevents chip damage caused by excessive temperature, while current limit protects against overcurrent operation of the output switch.

II.Key Features

Wide input voltage range:4.5V to 40V, adapting to various power supply environments.

Fixed 300kHz switching frequency:Supports smaller filter components and improves space utilization.

Built-in switching MOSFET:150mΩ internal power MOSFET saves space and simplifies external circuit design.

High operating efficiency:Conversion efficiency up to 91%.

Low-power standby mode:Standby current 0.1μA, extending device operating time.

High duty cycle:Maximum duty cycle 100%.

Protection functions:Cycle-by-cycle overcurrent protection, thermal shutdown protection.

Enable pin control input:Controlled by logic level for easy integration.

Output load current:Maximum load 5A, adapting to different power requirements.

III.Applications

Power Meters

Distributed Power Systems

Battery Chargers

LED Drivers

IV.Pin Description

XBL1663 Pin Diagram

NC: Not connected.

VIN: Supply voltage. XBL1663 operates with adjustable voltage from 4.5V to 40V. Ci is required to prevent large voltage spikes at the input terminal.

EN: Enable pin. Device shuts down below 1.2V and operates at 1.35V or above.

NC: Not connected.

FB: Feedback, sets the output voltage. When the FB voltage is below 300mV, the frequency foldback comparator reduces the oscillator frequency to prevent loss of current mode control during short-circuit faults.

NC: Not connected.

GND: Ground, voltage reference for regulated output voltage. Special layout considerations are required to isolate this node from the D1 to C1 ground path to prevent inductive switching current spikes.

SW: Power switch output. It is the drain of the N-channel power MOSFET, supplying the output Lc filter.

V.Electrical Characteristics

Input supply voltage: 4.5V to 40V.

Quiescent current: 2.8mA to 3mA.

Oscillation frequency: 240kHz to 360kHz.

Switch current limit: 8A.

Maximum duty cycle: 100%.

Conversion efficiency: Up to 91%.

Absolute Maximum Ratings

VI.Typical Application Circuit

XBL1663 is a current-mode step-down regulator. The EA output voltage is proportional to the peak inductor current. At the beginning of the cycle, M1 is off. The EA output voltage is higher than the current sense amplifier output, the current comparator output is low, and the rising edge of the 300kHz CLK signal sets the RS flip-flop. Its output turns on M1, connecting the SW pin and inductor to the input supply. The current sense amplifier detects and amplifies the rising inductor current, adds slope compensation to the current sense amplifier output, and compares it with the error amplifier output at the PWM comparator. When the sum of the current sense amplifier output and the slope compensation signal exceeds the EA output voltage, the RS flip-flop resets and M1 turns off. The external Schottky rectifier diode (D1) conducts the inductor current. If the sum of the current sense amplifier output and the slope compensation signal does not exceed the EA output during the entire cycle, the falling edge of CLK resets the flip-flop. An FB pin voltage below 0.750V increases the EA output voltage. Since the EA output voltage is proportional to the peak inductor current, an increase in its voltage also increases the current delivered to the output.

VII.Ordering Information

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