RT6150A

Part: RT6150A/B from Richtek Technology Corporation

Type: Current Mode Buck-Boost DC/DC Converter

Key Specs:

• Input Voltage Range: 1.8V to 5.5V
• Continuous Output Current: Up to 800mA
• Switching Frequency: 1MHz
• Quiescent Current (Power Save Mode): 60μA (typical)
• Shutdown Current: 0.1μA (typical)
• Efficiency: Up to 90%
• Output Voltage Options: Fixed 3.3V, Adjustable 1.8V to 5.5V

Features:

• Single Inductor
• Fixed Frequency Operation
• Synchronous Rectification
• VOUT Disconnected from VIN during Shutdown
• Power Save Mode (PSM) Enable Control
• Internal soft-start control
• Thermal shutdown protection
• Current limit
• RoHS Compliant and Halogen Free

Applications:

• Portable Products
• Handheld Instrumentation

Package:

• WDFN-10L 3x3 (for RT6150A)
• WDFN-10L 2.5x2.5 (for RT6150B)

• Single Inductor
• Fixed Frequency Operation with Battery Voltages
• Synchronous Rectification : Up to 90% Efficiency
• Up to 800mA Continuous Output Current
• VOUT Disconnected from VIN during Shutdown
• Power Save Mode (PSM) Enable Control
• <1μA Shutdown Current
• Input Voltage Range: 1.8V to 5.5V
• Fixed 3.3V and Adjustable Output Voltage Options from 1.8V to 5.5V
• 10-Lead WDFN Packages
• RoHS Compliant and Halogen Free

• Portable Products
• Handheld Instrumentation

Features

• Single Inductor
• Fixed Frequency Operation with Battery Voltages
• Synchronous Rectification : Up to 90% Efficiency
• Up to 800mA Continuous Output Current
• VOUT Disconnected from VIN during Shutdown
• Power Save Mode (PSM) Enable Control
• <1μA Shutdown Current
• Input Voltage Range: 1.8V to 5.5V
• Fixed 3.3V and Adjustable Output Voltage Options from 1.8V to 5.5V
• 10-Lead WDFN Packages
• RoHS Compliant and Halogen Free

WDFN-10L 3x3 / WDFN-10L 2.5x2.5

RT6150BGQW

00 : Product Code W : Date Code

RT6150B-33GQW

03: Product Code W: Date Code

Functional Pin Description

Pin No.	Pin Name	Pin Function
1	VOUT	Output of the Buck-Boost Converter. Connect a capacitor between the VOUT and GND.
2	LX2	Second Switch Node. Connect this pin to the inductor.
3, 9, 11 (Exposed Pad)	GND	Power Ground. The exposed pad must be soldered to a large PCB and connected to GND for maximum power dissipation.
4	LX1	First Switch Node. Connect this pin to the inductor.
5	VIN	Power Input. Connect an at least 10μ F capacitor between the VIN pin and GND.
6	EN	Enable Control Input for the Buck-Boost Converter.
7	PS	PSM Control Input. Pull low for PSM operation and pull high for fixed switching frequency operation.
8	VINA	Supply Voltage Input for Control Circuit.
10	FB	Feedback Input. For adjustable versions, connect a resistive divider to set the output voltage and it can be adjusted from 1.8V to 5.5V; For fixed version, must be connected to VOUT.

Function Block Diagram

Operation

The RT6150A/B is a synchronous average current mode switching Buck-Boost converter designed to maintain a fixed output voltage from an input supply that can be above, equal, or below the output voltage. The average inductor current is regulated by a fast current regulator which is controlled by a voltage control loop. The voltage error amplifier gets its feedback input from the FB pin. For adjustable output voltage, a resistive voltage divider must be connected to the FB pin. When VIN is greater than VOUT, the device operates in Buck mode. When VIN is lower than VOUT, the device operates in Boost mode. When VIN is close to VOUT, the RT6150A/B automatically enters Buck-Boost mode. In Buck-Boost mode, the converter will maintain the regulation for output voltage and keep a minimum current ripple in the inductor to guarantee good performance.

( V_IN = V_OUT = 3.6V , T_A = 25 °C, unless otherwise specified.)

Parameter		Symbol	Test Conditions	Min	Typ	Max	Unit
Input Voltage UVLO	High-Level				1.65	1.8	1.8 V
	Low-Level			1.4	1.55		V
Feedback Volta	ge	V FB	VPS = VIN	0.495	0.5	0.505	V
Feedback Input	Current		V FB = 0.5V		1	50	nA
Quiescent Current			I OUT = 0mA, PS = 0V (Note 5) Power Save Mode	60			μA
			EN = 0V, Not Including Switch Leakage Shutdown		0.1	1
N-MOSFET Switch Leakage					0.1	5	μA
P-MOSFET Sw	P-MOSFET Switch Leakage				0.1	10	μA
N-MOSFET Switch On Resistance		R DS(ON)_N			0.15		Ω
P-MOSFET Switch On Resistance		R DS(ON) _P			0.15		Ω
Switch Current Limit		I LIM	V IN = 3.6V	1.6			Α
Oscillator Frequency		fosc		0.8	1	1.2	MHz
Soft-Start Time		tss	Time from when EN signal asserts to output voltage IOUT = 0mA		0.65	1	ms

• Note 1. Stresses beyond those listed "Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions may affect device reliability.
• Note 2. θJA is measured at TA = 25°C on a high effective thermal conductivity four-layer test board per JEDEC 51-7. θJC is measured at the exposed pad of the package.
• Note 3. Devices are ESD sensitive. Handling precaution is recommended.
• Note 4. The device is not guaranteed to function outside its operating conditions.
• Note 5. Current measurements are performed when the output are not switching.

• Ambient Temperature Range ----- ---- -40°C to 85°C

Electrical Characteristics

( V_IN = V_OUT = 3.6V , T_A = 25 °C, unless otherwise specified.)

Parameter		Symbol	Test Conditions	Min	Typ	Max	Unit
Input Voltage UVLO	High-Level				1.65	1.8	1.8 V
	Low-Level			1.4	1.55		V
Feedback Volta	ge	V FB	VPS = VIN	0.495	0.5	0.505	V
Feedback Input	Current		V FB = 0.5V		1	50	nA
Quiescent Current			I OUT = 0mA, PS = 0V (Note 5) Power Save Mode	60			μA
			EN = 0V, Not Including Switch Leakage Shutdown		0.1	1
N-MOSFET Switch Leakage					0.1	5	μA
P-MOSFET Sw	P-MOSFET Switch Leakage				0.1	10	μA
N-MOSFET Switch On Resistance		R DS(ON)_N			0.15		Ω
P-MOSFET Switch On Resistance		R DS(ON) _P			0.15		Ω
Switch Current Limit		I LIM	V IN = 3.6V	1.6			Α
Oscillator Frequency		fosc		0.8	1	1.2	MHz
Soft-Start Time		tss	Time from when EN signal asserts to output voltage IOUT = 0mA		0.65	1	ms

• Note 1. Stresses beyond those listed "Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions may affect device reliability.
• Note 2. θJA is measured at TA = 25°C on a high effective thermal conductivity four-layer test board per JEDEC 51-7. θJC is measured at the exposed pad of the package.
• Note 3. Devices are ESD sensitive. Handling precaution is recommended.
• Note 4. The device is not guaranteed to function outside its operating conditions.
• Note 5. Current measurements are performed when the output are not switching.

The device has a built-in temperature sensor which monitors the internal junction temperature. If the temperature exceeds the threshold, the device stops operating. As soon as the IC temperature has decreased below the threshold with a hysteresis, it starts operating again. The built-in hysteresis is designed to avoid unstable operation at IC temperatures near the over temperature threshold.