Datasheet M62212P, M62212GP, M62212FP Datasheet (Mitsubishi)

MITSUBISHI SEMICONDUCTORS <Standard Linear ICs>

DESCRIPTION

M62212 is designed as a general purpose DC-DC converter.
This small 8 pin package contains many functions allowing
simpler peripheral circuits and compact set design.
The output transistor is open collector and emitter follower
type. This makes the control STEP-UP,STEP-DOWN and
INVERTING converter.

FEATURE

• Wide operation power supply voltage range •••••••2.5 ~ 18V

• Low power consumption••••••••••••••••••••••••1.3mA typ

• 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

• Package variation : 8pin DIP/SOP/SSOP8

M62212P/FP/GP

GENERAL PURPOSE DC-DC CONVERTER

PIN CONFIGURATION(TOP VIEW)

Collector
output

Emitter
output

GND

Cosc

1
2
3
4

OUTLINE 8P2S-A (FP)
8P2X (GP)
8P4 (P)

M62212P /

FP / GP

8
7

6
5

VCC

IN
FB
DTC

APPLICATIONS

General electric products, DC-DC converter

BLOCK DIAGRAM

COSC

IN

4

7

OSC

VCC

OP Amp

1.25V

1.25V

PWM Comp

VCC

VCC

8

U V L O
VTH : 2.3V

Short protection
circuit

1.86V

Collector

1

output

Emitter

2

output

R

Q

S

FB

6

5

DTC

( / 8 )

1

1.15V 0.3V

3

GND

MITSUBISHI SEMICONDUCTORS <Standard Linear ICs>

M62212P/FP/GP

GENERAL PURPOSE DC-DC CONVERTER

ABSOLUTE MAXIMUM RATINGS (Ta=25°C, unless otherwise noted)

Symbols Items Conditions Ratings Units

Vcc

Vo

Pd

Ktheta
Topr
Tstg

Power supply voltage
Output voltage
Output currentIo
Power dissipation
Thermal derating ratio
Operating ambient temperature

Storage temperature

Ta=25°C
Ta>25°C

19
19

150

625 (P) 360(FP) 250(GP)

5.00 (P) 2.88 (FP) 2.00(GP)

-20°C ~ +85

-40°C ~ +125

mW/°C

V
V

mA

mW

°C
°C

Electrical Characteristics ( Ta=25°C, Vcc =12V, Cosc=100pF unless otherwise noted )

Block

All
device

Std.
voltage
section

Error
amp.
section

Oscil­lator
section

UVLO
section

Symbol Items Test condition

VCC

I CC ST

V REF

L INE

I B
A V
G B

+

VOM

-

VOM

+

I OM

-

I OM

f OSC

VOSCH

VOSCL

I OSC CH

I OSC DIS1

VTH ON
VTH OFF
VHYS Hysteresis

Range of power supply voltage
Standby current

Standard voltage

Line regulation
Input bias current
Open loop gain
Unity gain bandwidth

Output high voltage

Output low voltage

Output sink current

Output source current

Oscillation frequency

Upper limit voltage of oscillation waveform

Lower limit voltage of oscillation waveform

Cosc charge current
Cosc discharge current 1
Start-up threshold voltage
Shut-down threshold voltage

Output "OFF" status

Voltage follower

VCC=2.5 ~ 18V

VFB=1.86V
VIN =1V

VIN =1V 2.3
VIN =1V

VHYS = VTHON - VTHOFF

Min Typ Max

2.5 18

1.19 1.25 1.31

1.82 2.62

2.2 2.4

20 80

Limits

1.3 1.8

5 12

80

0.6

6

-60 -30

110

1.0

0.45

-40
10

2.25
50

500

400

Units

V

mA

V

mV

nA

dB

MHz

V

mV
mA

uA

kHz

V

V
uA
uA

V
V

mV

( / 8 )

2

MITSUBISHI SEMICONDUCTORS <Standard Linear ICs>

M62212P/FP/GP

GENERAL PURPOSE DC-DC CONVERTER

Electrical Characteristics ( Ta=25°C, Vcc =12V, Cosc=100pF unless otherwise noted )

Block

Short
pro­tection
circuit

Output
section

Symbol

VTH FB

VTH DTC
VTL DTC

I CH1
I DIS1
I CH2
I DIS2

I CL

VSAT1

VSAT2

Items Test condition

FB threshold voltage

Latch mode "H" threshold voltage
Latch mode "L" threshold voltage

DTC charge current when start-up
DTC discharge current 1

DTC charge current when stable state

DTC discharge current 2

Collector output leak current

Collector output saturation voltage 1
Collector output saturation voltage 2

VIN =1V,VDTC=0.7V
VIN =1V,VFB =2.11V
VIN =1V,VFB =2.11V
VDTC=0.7V,VFB =2.11V
VDTC=0.7V,VFB =2.11V
VDTC=0.7V,VFB = 0.7V

VDTC=0.2V,VFB =2.11V

VCE=18V , VCC=18V

Emitter GND,
IC=150mA,VE=0V

Emitter follower,
IE=50mA,VC=12V

Limits

Min Typ Max

1.86

1.15

0.3

-45
50

-10
15

-1 1

0.3

1.6

1.1

Units

V
V

V
µA
µA
µA
µA
µA

V

V

( / 8 )

3

MITSUBISHI SEMICONDUCTORS <Standard Linear ICs>

M62212P/FP/GP

GENERAL PURPOSE DC-DC CONVERTER

1. Application Circuit (STEP-DOWN converter with current buffer transistor)

L

VIN

D

R1

R2

2

COUT

COSC

CIN

8

4

1

M62212

VOUT

7

6 5 3

( / 8 )

4

MITSUBISHI SEMICONDUCTORS <Standard Linear ICs>

M62212P/FP/GP

GENERAL PURPOSE DC-DC CONVERTER

2. FUNCTION DESCRIPION

1) Soft Start (The peripheral circuit is shown in Fig.1)
When the power is turned ON, input terminal IN is 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

OSC

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.

1.0V

0.45V

(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

12KΩÅ`25KΩ.

( / 8 )

5

MITSUBISHI SEMICONDUCTORS <Standard Linear ICs>

M62212P/FP/GP

GENERAL PURPOSE 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 1.86V 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 )

6

MITSUBISHI SEMICONDUCTORS <Standard Linear ICs>

FB

DTC

DTC set up value (Tentative)

OSC

ON

OFF

ON ON ON ON ON ON ON ON ON ON

ON

ON

ON

ON

ON ON

ONON

ON OFF OFF

OFF OFF

OFF OFF OFF OFF

OFF OFF

OFF

OFF

I 1

I 2

I 3

45µ

50µ 45µ 45µ10µ 50µ 50µ 15µ10µ 10µ

ON/OFF control --> Activate

M62212P/FP/GP

GENERAL PURPOSE DC-DC CONVERTER

Comp1

CDTC

FB

1.25V
I 1

10µ

DTC

RDTC
90KΩ

(900mV)

SW2

SW1

I 3
60µ

1.86V

Vcc

I 2

35µ

1.15V 0.3V

Comp2

(Initial RESET)

R

Q

S

* SW1 and SW2 are turned ON by "H" signal.

2.0

1.15

1.0

0.45

0

Charge Discharge

Charge

Activate

Output short

[ I ] [ II ]

Fig.3 Short Protection Circuit and the Timing Chart of the Modes

Discharge

50µ

Charge

Charge Charge Discharge

[ III ]

Charge Discharge Discharge

Output short (Latch)

[ IV ]

( / 8 )

7

MITSUBISHI SEMICONDUCTORS <Standard Linear ICs>

M62212P/FP/GP

GENERAL PURPOSE DC-DC CONVERTER

3.CONSTANT DEFINITION

CONSTANT Step-down converter Step-up converter Inverting converter

VO + VF - VIN

VIN - VCE(sat)

1

fOSC

TON + TOFF

TON

1+

TOFF

1

-TOFF

fOSC

TON(MAX)
TON + TOFF
1

75 * 10 * fosc

(VIN -VCE(sat)) * TON(MAX) * fOSC

3

-16 * 10

2 2

-12

2 * VO * IO
VO

-1 * R2

VREF

VDTC(MAX)

| ICH1 |

VDTC(MAX)

| ICH2 |

| ICH1 | * tstart

VDTC(MAX)

IDIS1 * tshort

VDTC(MAX) -VOSCL

|Vo| + VF

VIN - VCE(sat)

1

fOSC

TON + TOFF

TON

1+

TOFF

1

-TOFF

fOSC

TON(MAX)

TON + TOFF

1

75 * 10 * fosc

(VIN -VCE(sat)) * TON(MAX) * fOSC

3

2 2

2 * VO * IO

|VO|

VREF

-1 *R2

VDTC(MAX)

| ICH1 |

VDTC(MAX)

| ICH2 |

| ICH1 | * tstart

VDTC(MAX)

IDIS1 * tshort

VDTC(MAX) -VOSCL

TON + TOFF

TOFF (MIN)

TON (MAX)

RDTC

(*4)

CDTC

(*4)

TON

TOFF

D (MAX)

COSC

L (MIN)

(*1)

R1

(*1,*2)

not use short
protection

use short
protection

calicurate from
start-up time

calicurate from
shat down time

VO + VF

VIN - VCE(sat) - VO

1

fOSC

TON + TOFF

TON

1 +

TOFF

1

-TOFF

fOSC

TON(MAX)
TON + TOFF
1

75 * 10 * fosc

(VIN - VCE(sat) - VO) * TON(MAX)

3

-16 * 10

-12

∆IO

VO

-1 * R2

VREF

VDTC(MAX)

| ICH1 |

VDTC(MAX)

| ICH2 |

| ICH1 | * tstart

VDTC(MAX)
IDIS1 * tshort

VDTC(MAX) -VOSCL

-16 * 10

-12

VF : Forward Voltage of outer Diode.
VCE(sat) : Saturation Voltage of M62212 or Saturation Voltage of Current buffer Transistor.
Åô Please setting the Oscillation frequency first and calicurate each constant value.

*1 : Please setting ŢIo about 1/3 to 1/5 of maximum output current.
*2 :|Vo|= (1+ ) * VREF

*3 : Please settng R2 about few KÉ∂ to score of KÉ∂ because output voltage don't
undergo
a influence of input current (Terminla 7).

*4 : Please setting VDTC(MAX) to satisfy D(MAX), fixed from caracteristics of D(MAX) - VDTC(MAX).

R1
R2

ICH1 means DTC charge current when start-up(-45µA typ), ICH2 means DTC charge current
when stable state(-10µA typ), VOSCL means lower limit vlage of oscillation waveform
(0.45V typ), and IDIS1 means DTC discharge current 1(50µA typ).

tstart means time internval when terminal vltage of DTC increase to VOSCL from lower voltage
and to start switching at first.

tshort means time interval when output is shut down after output is shorted.

( / 8 )

8