PicoBK MYRGM-X / MYRGM-C series
2.0A Inductor Built-in Step-Down DC/DC Converters
GreenOperationCompatible
GENERAL DESCRIPTION
The MYRGM-X/C series is a synchronous step-down micro DC/DC converter
which integrates an inductor and a control IC in one tiny package (3.1mm4.7mm, h=1.3mm).
An internal coil simplifies the circuit and enables minimization of noise and
other operational trouble due to the circuit wiring.
A wide operating voltage range of 2.7V to 6.0V enables support for applications
that require an externally set output voltage can be selected.
The MYRGM-X/C series use synchronous rectification at an operating frequency of 2.4MHz.
PWM control (MYRGM-X) or automatic PWM/PFM switching control (MYRGM-C) can be selected.
The MYRGM-X series has a fixed frequency, enabling the suppression of output ripple.
The MYRGM-C series achieves high efficiency while holding down output ripple
across the full range of loads, from light to heavy, enabling the extension of battery operation time.
The series have a high speed soft-start as fast as 1ms in typical for quick turn-on. With the built-in UVLO (Under Voltage Lock
Out) function, the internal P-channel driver transistor is forced OFF when input voltage becomes 2.4V or lower. Its suitable for
large-current application due to limit current is configured 4.0A in typical. The integrated CL discharge function which enables the
electric charge at the output capacitor CL to be discharged via the internal discharge switch located between the LX and GND
pins. Due to C discharge function, malfunction on LX is prevented when Stand-by mode.
L
FEATURES
APPLICATIONS
Package Size
: 3.1mm4.7mm, h=1.3mm
Note PCs
Input Voltage
Printers : 2.7V6.0V
Tablet PCs
Output Voltage : 0.9VVIN (FB Voltage=0.8V2%)
PND(Portable Navigation Device)
High Efficiency
: 94% (VIN=5.0V, VOUT=3.3V)
Output Current
: 2.0A
Switching Frequency
: 2.4MHz (15%)
Maximum Duty Cycle
: 100%
Control Methods
: PWM (MYRGM-X)
PWM/PFM (MYRGM-C)
Functions
: Current Limit Circuit (automatic return)
Soft-Start Circuit Built-In
CL Discharge, UVLO
Output Capacitor : Low ESR Ceramic Capacitor
Operating Ambient Temperature : -40+85
Environmentally Friendly : EU RoHS Compliant, Pb Free
Halogen Free
TYPICAL PERFORMANCE
TYPICAL APPLICATIONCIRCUIT
CHARACTERISTICS
MYRGM080200X41RA /MYRGM080200C41RA
100
MYRGM-C
80
Lx
L1
CE
VIN
MYRGM-X
PVIN
VOUT 60
L2
R1
AVIN
CFB
40
CIN1
FB
CIN2 V =5.0V
GND IN
CL R2
V =3.3V
OUT
20
0
0.1 1 10 100 1000 10000
Output Current : I (mA)
OUT
Export Control Code : X0863, Document No : D90DH00053
MYRGM-X/C series A01 Page 1 of 17
Efficiency : EFFI (%)PicoBK MYRGM-X / MYRGM-C series
2.0A Inductor Built-in Step-Down DC/DC Converters
BLOCK DIAGRAM
MYRGM-X/C series
Inductor
L2 L1
UVLO Cmp
AVIN UVLO
R1
PVIN
Current Feedback
Current Limit
R2
Error
PWM
Amp.
Comparator
FB
Synch
Logic
Buffer Lx
Drive
Vref with Phase Ramp Wave
Soft Start,
Generator
Compensation
CE OSC
CE/B
CE
Thermal
PWM/PFM
Control
CE
Shutdoun
Logic Selector
GND
* The MYRGM-X series offers a fixed PWM control, a Control Logic of PWM/PFM Selector is fixed at PWM internally.
The MYRGM-C series control scheme is a fixed PWM/PFM automatic switching, a Control Logic of PWM/PFM Selector is fixed at PWM/PFM
automatic switching internally.
Diodes inside the circuit are an ESD protection diode and a parasitic diode.
MYRGM-X/C series A01 Page 2 of 17