Ordering number : ENA1900
Bi-CMOS IC
LV5818M
Step-down Switching Regulator
Overview
LV5818M is a 1ch step-down switching regulator. 0.3Ω FET is incorporated on the upper side to achieve high-efficiency
operation for large output current. Low-heat resistance and compact-package MFP12 employed. Current mode control
type, with superior load current response and easy phase compensation EN pin, allowing the standby mode with the current
drain of 70μA or less Pulse-by-pulse over-current protection and overheat protection available for protection of load
devices Soft start pin to be provided with a capacitance for soft start.
Functions
• 2A 1ch step-down switching regulator
• Wide input dynamic range ( to 28V)
• High efficiency (90% IOUT = 1A, VIN = 12V, VO = 5V)
• Standby mode
• Over-current protection
• External synchronous driving
• Thermal shutdown
• Reference voltage: 0.8V
• The frequency is changeable in external resistance.
• Soft start
• Compact package: MFP12
Specifications
Maximum Ratings at Ta = 25°C
Parameter
Symbol
Conditions
Ratings
Unit
Maximum input VIN voltage
VIN max
32
V
BOOT pin maximum voltage
VBT max
37
V
SW pin maximum voltage
VSW max
VIN max
V
BOOT pin-SW pin maximum voltage
VBS-SW max
7
V
FB, EN, COMP, SS, SYNC, RT pin
Vfs max
7
V
maximum voltage
Allowable power dissipation
Pd max
Junction temperature
Tj max
Operating temperature
Storage temperature
Mount on a specified board *
1.65
W
150
°C
Topr
-20 to 80
°C
Tstg
-40 to 150
°C
* Specified board: 46.4mm × 31.8mm ×1.7mm, glass epoxy both side.
Note: Plan the maximum voltage while including coil and surge voltages, so that the maximum voltage is not exceeded even for an instant.
Any and all SANYO Semiconductor Co.,Ltd. products described or contained herein are, with regard to
"standard application", intended for the use as general electronics equipment (home appliances, AV equipment,
communication device, office equipment, industrial equipment etc.). The products mentioned herein shall not be
intended for use for any "special application" (medical equipment whose purpose is to sustain life, aerospace
instrument, nuclear control device, burning appliances, transportation machine, traffic signal system, safety
equipment etc.) that shall require extremely high level of reliability and can directly threaten human lives in case
of failure or malfunction of the product or may cause harm to human bodies, nor shall they grant any guarantee
thereof. If you should intend to use our products for applications outside the standard applications of our
customer who is considering such use and/or outside the scope of our intended standard applications, please
consult with us prior to the intended use. If there is no consultation or inquiry before the intended use, our
customer shall be solely responsible for the use.
Specifications of any and all SANYO Semiconductor Co.,Ltd. products described or contained herein stipulate
the performance, characteristics, and functions of the described products in the independent state, and are not
guarantees of the performance, characteristics, and functions of the described products as mounted in the
customer' s products or equipment. To verify symptoms and states that cannot be evaluated in an independent
device, the customer should always evaluate and test devices mounted in the customer' s products or
equipment.
D0810 SY 20101130-S00002 No.A1900-1/6
LV5818M
Recommended Operating Conditions at Ta = 25°C
Parameter
Symbol
Conditions
Ratings
Unit
VIN pin voltage
VIN
8 to 28
BOOT pin voltage
VBT
-0.3 to 34
V
V
SW pin voltage
VSW
-0.4 to VIN
V
BOOT pin-SW pin maximum
VBS-SW
6.5
V
VFSO
6
V
FOSC
60k to 1M
Hz
voltage
FB, EN, COMP, SS, SYNC, RT
pin voltage
Operating frequency
Electrical Characteristics at Ta = 25°C, VIN = 12V, unless otherwise specified.
Parameter
Symbol
Conditions
IC current drain at standby
ICC1
EN=0V
IC current drain in operation
ICC2
EN=OPEN
Efficiency
Effcy
VIN=12V, IOUT=1A, Vo=5V, RT=100kΩ
Design target *1
Reference voltage
Vref
VIN=8V to 28V (±2%)
FB pin bias current
Iref
High-side ON resistance
RonH
Low-side ON resistance
RonL
Ratings
min
typ
-2%
Unit
max
70
μA
5
mA
90
%
0.8
+2%
V
FB=0.8V application
10
100
nA
BOOT=5V
0.3
Ω
6
Ω
Oscillation frequency
fOSC
RT=100kΩ
290
325
360
kHz
Oscillation frequency during
short-circuit protection
fOSCS
RT=100kΩ
48
60
72
kHz
EN high-threshold voltage
Venh
1.9
V
EN low-threshold voltage
Venl
EN pull up current
Ien
SYNC pin threshold
VsyncH
0.8
EN = 0V
V
μA
16
2.6
V
High-voltage
SYNC pin threshold Low-voltage
VsyncL
Maximum ON DUTY
D max
0.8
Current limit peak value
Icl1
VIN=12V, VOUT=5V, L=10μH
Thermal shutdown temperature
Ttsd
Thermal shutdown temperature
hysteresis
Soft start current
V
80
%
*Design guarantee *2
160
°C
Dtsd
*Design guarantee *2
40
°C
ISS
SS=0V
3
6
A
10
14
μA
*1: Reference value (not tested before shipment)
*2: Design guarantee (value guaranteed by design and not tested before shipment)
Pin Assignment
BOOT 1
12 SYNC
VIN 2
11 RT
VIN 3
10 SS
SW 4
9 EN
SW 5
8 COMP
GND 6
7 FB
Top view
No.A1900-2/6
LV5818M
Package Dimensions
unit : mm (typ)
3384
SIDE VIEW
BOTTOM VIEW
5.0
Allowable power dissipation, Pd max -- W
TOP VIEW
2.0
(3.4)
(2.6)
0.63
6.4
4.4
12
1
2
0.15
0.3
0.8
Mounted on a specified board: 46.4×31.8×1.7mm3
glass epoxy both side
1.65
1.0
(0.5)
1.7 MAX
0
-20
0.92
0
20
40
60
80
Ambient temperature, Ta -- C
0.05
(1.5)
SIDE VIEW
Pd max -- Ta
SANYO : MFP12S(225mil)
Block Diagram and Sample Application Circuit (3.3V output)
BOOT (SW + Vreg.)
BOOT
UVLO
VIN=12V
SYNC
+
Current Sense
Amp.
RT
Pre-Drive
OSC
+
FB
Error
Amp.
+
PWM
comparator
Pre-Drive
COMP
C4=OPEN
C3=
6800pF
+
SS
EN
H : ON or OPEN
Internal Stable
supply
Vref
0.8V
Current
Limit
Comparator
SW
VOUT=3.3V
D1=SBM30-03
1:N
GND
VIN
TSD
Internal
Regulator
Internal Regulator
(5V)
L : OFF
C1,C8,C5,C9 = Ceramic capacitor
L1 = CDRH105RNP-100NC (sumida)
No.A1900-3/6
100
LV5818M
Pin Function
Pin No.
1
2,3
4,5
Pin name
BOOT
Function
Equivalent circuit
Upper MOS transistor boot strap capacitance connection pin.
Connect the boot capacitance of about 0.01μF between SW
pins.
To protect the SW pin’s absolute maximum rating, to ensure
stable operation, and to eliminate noise, the boot capacitance
serial resistance (about 10Ω) Rb proves effective.
VIN
Input voltage pin.
Connect substantially large (20μF more) capacitance between
this pin and GND.
SW
Power switch pin.
Connect the output LC filter. Connect the above capacitance
between this pin and BOOT pin.
VIN
BOOT
Hi side MOS
SW
Low side MOS
GND
6
GND
Ground pin.
7
FB
Feedback pin.
Sets the output voltage by means of split resistor in the section
of the output voltage VOUT - FB - GND. VOUT setting is made
as calculated below:
VOUT = Vref × { 1 +
(R1 + R10)
}
R3
VIN
internal regulation line
Vref = 0.8V
Example: 3.3V output voltage
(See Block Diagram and Sample Application Circuit)
VOUT = 0.8 × { 1 +
10
SS
(27k + 4.3k)
}
10k
=3.304V
Soft start pin.
Sets the soft start time by means of the built-in 10μA source
voltage and external soft start capacity. The soft start capacity
C6 can be set as follows:
SS
FB
VREF
0.8V
Tss
C6 = 10μA × Vref
Where, Tss is the soft start time and Vref is the reference
voltage.
Example: 1.2ms soft start time achieved
1.2ms
C6 = 10μA × 0.8 V = 0.015μF
8
COMP
Phase compensation pin.
Connects with the phase compensation external capacitance
and resistance of DC/DC converter close loop.
VIN
internal reguration line
COMP
Clamp circuit
7
EN
Enable pin.
Converter enabled when set to the HIGH voltage and disabled
when LOW voltage or OPEN state.
VIN
EN
2pF
Q117
Continued on next page.
No.A1900-4/6
LV5818M
Continued from preceding page.
Pin No.
11
Pin name
RT
Function
Equivalent circuit
RT pin.
To set the frequency, resistance is connected.
VIN
RT
12
SYNC
SYNC pin.
The external cycle clock is impressed.
VIN
SYNC
Considerations for the design
Insertion of serial beads in the Schottky diode for removal of noise may cause generation of the negative voltage
deviating from the absolute maximum rating at the SW pin, resulting in failure of normal operation. In such an event,
do not insert beads as above described and, instead, remove noise by means of the BOOT resistance Rb.
Please set the internal frequency decided by the terminal RT about 50kHz lower than an external input frequency when
you use the external cycle function.
PS No.A1900-5/6
LV5818M
Reference data
RT - Freq
1000
Oscllatory frequency , Freq - kHz
900
800
700
600
500
400
300
200
100
0
10
100
1000
SANYO Semiconductor Co.,Ltd. assumes no responsibility for equipment failures that result from using
products at values that exceed, even momentarily, rated values (such as maximum ratings, operating condition
ranges, or other parameters) listed in products specifications of any and all SANYO Semiconductor Co.,Ltd.
products described or contained herein.
SANYO Semiconductor Co.,Ltd. strives to supply high-quality high-reliability products, however, any and all
semiconductor products fail or malfunction with some probability. It is possible that these probabilistic failures or
malfunction could give rise to accidents or events that could endanger human lives, trouble that could give rise
to smoke or fire, or accidents that could cause damage to other property. When designing equipment, adopt
safety measures so that these kinds of accidents or events cannot occur. Such measures include but are not
limited to protective circuits and error prevention circuits for safe design, redundant design, and structural
design.
In the event that any or all SANYO Semiconductor Co.,Ltd. products described or contained herein are
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Any and all information described or contained herein are subject to change without notice due to
product/technology improvement, etc. When designing equipment, refer to the "Delivery Specification" for the
SANYO Semiconductor Co.,Ltd. product that you intend to use.
Information (including circuit diagrams and circuit parameters) herein is for example only; it is not guaranteed
for volume production.
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above.
This catalog provides information as of December, 2010. Specifications and information herein are subject
to change without notice.
PS No.A1900-6/6