Mitsubishi M62210FP General purpose multi function dc-dc converter Datasheet

MITSUBISHI SEMICONDUCTORS <DIGI•ANA INTERFACE>
M62210FP
GENERAL PURPOSE MULTI FUNCTION DC-DC CONVERTER
Notice: This is not a final specification.
Some parametric limits are subject to change.
DESCRIPTION
M62210FP is designed as a general purpose multi-function
DC-DC converter. This is most suitable as a back-light control
for a LCD,etc.
This small 10 pin package contains many functions allowing
simpler peripheral circuits and compact set design.
The input of this unit has two channels containing priority
control circuit. This makes the control a simple matter when
the back-light is on and during the stable state.
PIN CONFIGURATION(TOP VIEW)
Collector
output
1
10
VCC
Emitter
output
2
9
IN1
GND
3
8
IN2
COSC
4
7
FB
TIN
5
6
DTC
FEATURE
Wide operation power supply voltage range…………2.5~18V
Low power consumption ………………………………1.3mA typ
Operation can be synchronized by the external sync signal
Operation can be controlled using two prioritized systems.
(High input has priority)
High speed switching is possible.(300kHz)
Output short protection circuit and ON/OFF control are used.
The dead-time control and the soft-start operation are
possible
Small size 10-pin SOP package.
OUTLINE 10P2
APPLICATIONS
Back-light control of personal computers and word processors
General electric products
BLOCK DIAGRAM
VCC
10
TIN 5
OSC &
sync ckt
UVLO
V TH : 2.3V
COSC 4
VCC
1
PWM Comp
OP Amp1
Collector
output
IN1 9
2 Emitter
output
Std. voltage
1.25V
Short protection
circuit
1.25V
1.25V
IN2 8
R
OP Amp2
S Q
1.15V
7
FB
6
DTC
( 1 / 9 )
3
GND
0.3V
MITSUBISHI SEMICONDUCTORS <DIGI•ANA INTERFACE>
M62210FP
GENERAL PURPOSE MULTI FUNCTION DC-DC CONVERTER
ABSOLUTE MAXIMUM RATINGS (Ta=25ºC unless otherwise noted)
Symbols
Items
Conditions
Ratings
Units
Vcc
Power supply voltage
19
V
Vo
Output voltage
19
V
Io
Output current
150
mA
Pd
Power dissipation
Ta=25ºC
360
mW
K
Thermal derating ratio
Ta>25ºC
2.88
mW/ºC
Topr
Operating ambient temperature
Storage temperature
Tstg
-20ºC~+85
ºC
-40ºC~+125
ºC
Electrical Characteristics ( Ta=25ºC, Vcc =12V, Cosc=100pF unless otherwise noted )
Block
Symbol
All
device
VCC
Range of power supply voltage
I CC ST
Standby current
Output "OFF" status
Std.
voltage
section
V REF
Standard voltage
Voltage follower
L INE
Line regulation
VCC=2.5~18V
IB
Input bias current
AV
Open loop gain
Error
amp.
section
GB
VOM
VOM
-
I OM
+
-
f OSC
Oscillator
section
Test condition
Limits
Min
2.5
1.19
Unity gain bandwidth
+
I OM
Items
Typ
VFB=1.25V
Output source current
VIN1=1V , VIN2=1V
mA
1.25
1.31
V
5
12
mV
500
nA
80
dB
0.6
MHz
2.5
V
400
mV
mA
6
-60
Oscillation frequency
V
1.8
Output low voltage
Output sink current
Units
1.3
1.7
Output high voltage
Max
18
-30
uA
110
kHz
VOSCH
Upper limit voltage of oscillation waveform
1.0
V
VOSCL
Lower limit voltage of oscillation waveform
0.45
V
I OSC CH
Cosc charge current
-40
uA
I OSC DIS1
Cosc discharge current 1
10
uA
40
I OSC DIS2
Cosc discharge current 2
VTINH
TIN "H" level
VTINL
TIN "L" level
2.2
( 2 / 9 )
uA
V CC
V
1.0
V
MITSUBISHI SEMICONDUCTORS <DIGI•ANA INTERFACE>
M62210FP
GENERAL PURPOSE MULTI FUNCTION DC-DC CONVERTER
Electrical Characteristics ( Ta=25ºC, Vcc =12V, Cosc=100pF unless otherwise noted )
Block
UVLO
section
Short
protec
tion
circuit
Output
section
Items
Symbol
Limits
Test condition
Min
VTH ON
Start-up threshold voltage
VIN1=1V , VIN2=1V
VTH OFF
Shut-down threshold voltage
VIN1=1V , VIN2=1V
2.2
Typ
Max
2.3
2.4
2.25
Units
V
V
VHYS
Hysteresis
VHYS = VTHON - VTHOFF
VTH FB
FB threshold voltage
VIN1=1V,VIN2=1V,VDTC=0.7V
1.25
V
VTH DTC
Latch mode "H" threshold voltage
VIN1=1V,VIN2=1V,VFB =1.5V
1.15
V
VTL DTC
Latch mode "L" threshold voltage
VIN1=1V,VIN2=1V,VFB =1.5V
0.3
V
I CH1
DTC charge current when start-up
VDTC=0.7V,VFB =1.5V
-45
µA
I DIS1
DTC discharge current 1
VDTC=0.7V,VFB =1.5V
50
µA
I CH2
DTC charge current when stable state VDTC=0.7V,VFB = 0.7V
-10
µA
I DIS2
DTC discharge current 2
VDTC=0.2V,VFB =1.5V
15
µA
I CL
Collector output leak current
VCE=18V , VCC=18V
VSAT1
Collector output saturation voltage 1
VSAT2
Collector output saturation voltage 2
Emitter GND,
IC=150mA,VE=0V
Emitter follower,
IE=50mA,VC=12V
( 3 / 9 )
20
50
-1
0.3
1.6
80
mV
1
µA
1.1
V
V
MITSUBISHI SEMICONDUCTORS <DIGI•ANA INTERFACE>
M62210FP
GENERAL PURPOSE MULTI FUNCTION DC-DC CONVERTER
1. Explanation of Back Light Control Circuit
VCC
DC/AC
D1
Cl
Co
OSC &
sync ckt
UVLO
VTH :2.3V
FL
Tube
Cosc
R1
OP Amp1
IN1
D2
R3
Std. voltage
1.25V
VR1
IN2
R
OP Amp2
RFL
R2
R4
CDELAY
CFL
S Q
Cf2
Cf1
RDTC
CDTC
Rl1
Rl2
Fig.1 An Application of the Back Light Control Circuit
1-1. Priority Control Operation
As far as OPAmp1 and OPAmp2 are concerned, there is no problem when either IN1 or IN2 is
used to control current, since the setting up to lower the output voltage of the DC-DC converter is
prioritized. (The above figure uses IN1 to control current.)
1)
When starting, the output voltage "Vo" is determined by the feedback to IN2 via R1 and
R2 and the following equation :
Vo=VREF x (R1 + R2)/R2 (VREF =1.25Vtyp) (Area of the Timing Chart 1)
2)
Next, this output voltage "Vo" is used to discharge the FL tube by the inverter and causes
the tube current to flow. The tube current is filtered and smoothed by RFL, D2, and CFL so
that the DC voltage (VCFL) corresponding to the tube current is generated at CFL.
The voltage of VCFL is divided by R3, VR1, and R4, and feedback to IN1, it can control tube
current. (Area of the Timing Chart 2)
3)
Here, CDELAY is inserted between R3 and VR1 + R4 in order to regulate the timing to switch
from the voltage control to the current control. (Area of the Timing Chart 3)
4)
When in the current control state, it is possible to adjust brightness by changing the
amount of feedback of the tube current using VR1. (Area of the Timing Chart 4)
5)
If the feedback used for controlling current is lost due to irregularities in the FL tube. etc..
the control returns to the voltage control mode. (Area of the Timing Chart 5)
( 4 / 9 )
MITSUBISHI SEMICONDUCTORS <DIGI•ANA INTERFACE>
M62210FP
GENERAL PURPOSE MULTI FUNCTION DC-DC CONVERTER
<Timing Chart>
(V)
(mArms)
(V)
(V)
II
I
III
IV
( 5 / 9 )
V
MITSUBISHI SEMICONDUCTORS <DIGI•ANA INTERFACE>
M62210FP
GENERAL PURPOSE MULTI FUNCTION DC-DC CONVERTER
1-2 Setting Up TIN
1) Setting Up the Level
The TIN terminal is shown in Fig.a. In order for the level of TIN to satisfy the conditions shown in
the table below, the external circuits shown in Fig.b or Fig.c should be used when the external
voltage level of the input is high.
100kΩ
TIN 5
5
5
Fig.b
Fig.c
50kΩ
3
GND
Fig.a
Items
Symbols
min
typ
max
Unit
TIN "H" level
VTINH
2.2
–
VCC
V
TIN "L" level
VTINL
–
–
1.0
V
2) Setting Up frequency
The periodical change of TIN is expected to be +30% ~ -20%. The fIN is set to
approximately 1.5 times fOSC
fIN = 1.5 • fOSC
•
fOSC =
•
COSC
TIN
( 6 / 9 )
1
1.3µs+(78x10 3xCOSC )
(Hz)
MITSUBISHI SEMICONDUCTORS <DIGI•ANA INTERFACE>
M62210FP
GENERAL PURPOSE MULTI FUNCTION DC-DC CONVERTER
1-3 Soft Start, DTC, and Short Protection
1) Soft Start (The peripheral circuit is shown in Fig.1)
When the power is turned ON, IN1 and IN2 are at 0V level. Therefore, the FB terminal
is fixed to High level. The DTC terminal goes up gradually starting from 0V due to the
internal charge current and the external CDTC.
When the level of DTC terminal reaches the lower limit of the triangular wave of the
oscillator, PWM comparator and the output circuit go into operation causing the output
voltage, "Vo" of the DC-DC converter to rise. The charge current is designed to be
approximately 45µA.
FB
DTC
1.0V
OSC
0.45V
OFF
External Tr collector
ON
Fig.2
2) DTC
The dead time control is set by installing a resistor between the DTC terminal and GND.
However, the DTC terminal serves as the short protection circuit also. Therefore, its set up
depends on whether the short protection circuit is used and not.
(When the short protection circuit is used)
At this time, the charge current for DTC is approximately 10µA. Therefore, RDTC should
be set to 40KΩ~110KΩ.
(When the short protection circuit is not used)
At this time, the charge current for DTC is approximately 45µA. Therefore, RDTC is set to
12KΩ~25KΩ.
( 7 / 9 )
MITSUBISHI SEMICONDUCTORS <DIGI•ANA INTERFACE>
M62210FP
GENERAL PURPOSE MULTI FUNCTION DC-DC CONVERTER
3) Short Protection Circuit
The Short Protection Circuit used the timer latch system. It is determined by setting the
capacity used for the soft start connected to the DTC terminal.
Fig.3 shows the short protection circuit and the timing chart for various modes.
When the power is turned on, the FB terminal goes high (approx. 2.3V) and the DTC
terminal goes low (goes up slowly from 0V). Thus, approximately 45µA current will flow
when SW1:ON and SW2:OFF. The potential, namely the potential of the FB terminal is in
the amplitude of the triangular wave, SW1 will be OFF and SW2 will be ON and approximately
50µA will flow into the DTC terminal. This discharge current will cause the DTC terminal to
drop from 1.15V.
At this time, if the potential of the FB terminal goes to the control potential before the
potential at the DTC terminal goes lower than 0.45V which is the lower limit value of the
triangular wave and if the potential of the FB terminal is lower than the potential of the DTC
terminal, then the system is activated.
When the output is shorted, the system is either activated or latched depending on
whether the time for the high potential of the FB terminal reaches the potential of the control
state is long or short. (For detail, see [II] and [IV] of the Mode)
There are two ways to go back to operation after the latch to shut off output. Either
method can restart with soft start.
1. Turning ON the Vcc.
2. Make the FB terminal to go to the low potential of 1.25V or less. Then, it is
cancel led.
[Mode Explained]
[ I ] Mode ……………… Activation
This is used when the FB terminal goes down to the control state potential when the DTC
terminal is in up slope. In order for the activation to occur when the DTC terminal is in down
slope, the FB terminal potential must go below the DTC terminal before the DTC terminal
goes to 0.45V.
[ II ] Mode ……………… Output short --> Activation
The system is activated if the FB terminal potential goes below the DTC terminal potential
before the DTC terminal goes to 0.45V. If there is not enough time, the output is turned OFF
(Latched)
[ III ] Mode ……………… ON/OFF Control --> Activation
This mode turns off the output by forcing the DTC terminal to go down. (The system)
returns as in the case of the activation.
[ IV ] Mode ……………… Output Short (Latch)
The output is turned OFF when the FB terminal potential did not go down to the control
state before the DTC terminal went down to 0.45V.
( 8 / 9 )
MITSUBISHI SEMICONDUCTORS <DIGI•ANA INTERFACE>
M62210FP
GENERAL PURPOSE MULTI FUNCTION DC-DC CONVERTER
Comp1
FB
(Initial RESET)
1.25V
R
Q
Vcc
1.25V
I2
35µ
I1
10µ
S
SW1
DTC
CDTC
Comp2
I3
60µ
RDTC
90kΩ
(900mV)
1.15V
0.3V
SW2
* SW1 and SW2 are turned ON by "H" signal.
FB
2.0
1.15
DTC
DTC set up value (Tentative)
1.0
OSC
0.45
0
I1
I2
I3
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
OFF
OFF
OFF
OFF
ON
ON
OFF
OFF
OFF
ON
OFF
ON
OFF
ON
OFF
OFF
OFF
ON
OFF
ON
ON
Charge Discharge
45µ
50µ
Charge
10µ
Discharge
50µ
Charge
10µ
Charge Charge Discharge
45µ
45µ
50µ
Charge
10µ
Discharge Discharge
15µ
50µ
Activate
Output short
ON/OFF control --> Activate
Output short (Latch)
[I]
[ II ]
[ III ]
[ IV ]
Fig.3 Short Protection Circuit and the Timing Chart of the Modes
( 9 / 9 )
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