Purpose
The startup voltage of the RT6154B is around 1.8V to 5.5V. When Input voltage is greater than 1.8V in light Load and heavy Load, the RT6154B feedback loop is internally compensated for both Buck and Boost operation and it provides seamless transition between Buck and Boost modes and optimal transient response.
Introduction
General Product Information
RT6154B is a high efficiency single inductor Buck-Boost Converter which can operate with wide input voltage such as battery which is higher or lower than the output voltage and it can supply the load current up to 4A. The maximum average current in the switches is limited to a typical value of 5A.
The RT6154B feedback loop is internally compensated for both Buck and Boost operation and it provides seamless transition between Buck and Boost modes and optimal transient response. The RT6154B operates at 2.4MHz typical switching frequency in full synchronous operation.
The RT6154B operates in Pulse Skipped Modulation (PSM) mode for increasing efficiency during low power RF transmission modes. The Power Save Mode can be disabled, forcing the RT6154B to operate at a fixed switching frequency. The RT6154B output voltage is fixed internally to 3.3V.
Product Feature
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Operates from a Single Li-ion Cell : 1.8V to 5.5V
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Fixed Output Voltage 3.3V
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PSM Operation
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3A Maximum Load Capability for VIN > 3.6V, VOUT = 3.3V
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2.4MHz (typ.) Switching Frequency
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Up to 96% Efficiency
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Input Over Current Limit
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Internal Compensation
Applications
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Cellular Phones
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Portable Hard Disk Drives
-
PDA
Key Performance Summary Table
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Key Features
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Evaluation Board Number : PCB054_V1
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|
Input Voltage Range
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1.8V to 5.5V
|
|
Switching Frequency
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2.4MHz
|
|
Max Output Current
|
4A
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Output Voltage
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Fixed 3.3V
|
|
Default Marking & Package Type
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RT6154BGQW, WDFN-14AL 4x3
|
Bench Test Setup Conditions
Headers Description and Placement
Please carefully inspect the EVB IC and external components, comparing them to the following Bill of Materials, to ensure that all components are installed and undamaged. If any components are missing or damaged during transportation, please contact the distributor or send e-mail to evb_service@richtek.com
Test Points
The EVB is provided with the test points and pin names listed in the table below.
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Test point/
Pin name
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Signal
|
Comment (expected waveforms or voltage levels on test points)
|
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VINA
|
Internal Driver voltage
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Analog VIN
|
|
GND
|
Analog Ground
|
Analog Ground.
|
|
FB
|
Reference voltage
|
Voltage feedback of adjustable versions, must be connected to VOUT on fixed output voltage versions.
|
|
EN
|
Enable Control
|
BUCK-boost converter output.
|
|
LX1
|
Switch Frequency
|
First switching node
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|
LX2
|
Switch Frequency
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Second switching node
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VIN
|
Input voltage
|
Power VIN
|
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EN
|
Enable Control
|
Enable input (1 enabled, 0 disabled), must not be left open.
|
|
PS/SYNC
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Enable/Disable Control Input
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Enable/disable power save mode (1 disabled, 0 enabled, clock signal for synchronization), must not be left open.
|
|
PG
|
Power Good Indicator Output.
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Output power good (1 good, 0 failure; open drain)
|
|
PGND
|
Power Ground
|
PGND
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Power-up & Measurement Procedure
1. Connect input power (1.8V < VIN < 5.5V) to VIN test pin.
2. EN short to VIN, PS/SYNC is Low or High, see SW switch is working.
3. Observe the output voltage is correct.
Operating Guideline
JP1 Setting
|
PS/SYNC Pin
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Operate Mode
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|
VIN
|
PWM
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|
GND
|
PSM
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JP2 Setting
|
Enable Pin (EN)
|
Function
|
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VIN
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Turn on
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GND
|
Turn off
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VOUT Setting
VOUT = 3.3V
Schematic, Bill of Materials & Board Layout
EVB Schematic Diagram
Bill of Materials
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Reference
|
Qty
|
Part Number
|
Description
|
Package
|
Manufacture
|
|
C1
|
1
|
C2012X5R1C106KTHN
|
10µF
|
0805
|
TDK
|
|
C2
|
1
|
C3216X5R0J476MT000N
|
47µF
|
1206
|
TDK
|
|
C3
|
1
|
C3216X5R0J476MT000N |
47µF
|
1206 |
TDK |
|
C6
|
1
|
|
NC
|
|
|
|
C7
|
1
|
C2012X5R1C106KTHN |
10µF
|
0805 |
TDK |
|
C9
|
1
|
|
NC
|
|
|
|
C10
|
1
|
C1608X7R1E104KT000N
|
0.1µF
|
0603
|
TDK
|
|
GP3
|
1
|
|
VIN
|
|
|
|
GP5
|
1
|
|
VOUT
|
|
|
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GP6, GP12, GP13
|
3
|
|
GND
|
|
|
|
GP7
|
1
|
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SCL
|
|
|
|
GP9
|
1
|
|
EN
|
|
|
|
GP10
|
1
|
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PS/SYNC
|
|
|
|
GP11
|
1
|
|
PG
|
|
|
|
GP14
|
1
|
|
VINA
|
|
|
|
GP15
|
1
|
|
SDA
|
|
|
|
JP1
|
1
|
|
PS/SYNC
|
|
|
|
JP2
|
1
|
|
EN
|
|
|
|
JP4
|
1
|
|
SIP-3P
|
|
|
|
L1
|
1
|
NRS5040T2R2NMGJ
|
2.2µH
|
5040
|
TAIYO YUDEN
|
|
R1
|
1
|
0603 1M00 1%
|
0Ω
|
0603
|
Walsin
|
|
R2
|
1
|
0603 1M00 1%
|
1MΩ
|
0603
|
Walsin
|
|
R3
|
1
|
|
NC
|
|
|
|
R6
|
1
|
|
NC
|
|
|
|
U1
|
1
|
RT6154BGQW
|
Buck-Boost Converter
|
WDFN-14AL 4x3
|
RICHTEK
|
|
Z1, Z2
|
2
|
|
FK_1
|
|
|
|
Z3, Z4, Z5, Z6
|
4
|
|
SIP-1P-M
|
|
|
PCB Layout
Top View
Bottom View