ROHM BD8179MUV Technical data

Power Supply IC Series for TFT-LCD Panels

5V Input Multi-channel System Power Supply IC

BD8179MUV

●Description

The BD8179MUV is a system power supply IC for TFT panels. A 1-chip IC providing a total of three voltages required for TFT panels, i.e., source voltage, gate high-level, and gate low-level voltage, thus constructing a TFT panel power supply with minimal components required.

●Features

1) Step Up DC/DC Converter.

2) Incorporates 18V, 3.0A N-channel FET

3) Linear-Regulator Controllers for V

4) 5 channel Operational Amplifiers/±150mA Output Short-Circuit Current 40V / µs Slew Rate

5) Switching Frequency: 1200 kHz.

6) Gate Shading Function Included.

7) Protection Circuits

8) Over Current Protection

9) Timer Latch Mode Short Current Protection.

10) Thermal Shut Down.

11) Under Voltage Protection.

12) Over Voltage Protection

13) VQFN032V5050 Package

●Applications

Liquid crystal TV, PC monitor, and TFT-LCD panel

●Absolute maximum ratings (Ta = 25℃)

GON and VGOFF

No.09035EBT04

Parameter Symbol Limit Unit

Power Supply Voltage VIN 7 V VMAIN Voltage VMAIN 20 V SUP Voltage VSUP 20 V DRVP Voltage VDRVP 40 V DRVN Voltage VDRVN -30 V SRC Voltage VSRC 40 V CTL Voltage VCTL 7 V Junction Temperature Tjmax 150 ℃ Power Dissipation Pd 4560 mW Operating Temperature Range Topr -40～85 ℃ Storage Temperature Range Tstg -55～150 ℃

* Reduced by 19.52 mW/℃ over 25℃, when mounted on a glass epoxy board. (4-layer 74.2 mm  74.2 mm  1.6 mm).

●Operating Condition

Parameter Symbol

Power Supply Voltage VIN 2.6 5.5 V VMAIN Voltage VMAIN 8 18 V SUP Voltage VSUP - 18 V DRVP Voltage VDRVP - 38 V DRVN Voltage VDRVN - -20 V SRC Voltage VSRC - 38 V

Limit

Min. Max.

Unit

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1/12

2009.07 - Rev.B

BD8179MUV

●Electrical Characteristics (Unless otherwise specified, VIN = 3.3V; VSUP = 12 V; VGON = 25 V; VGOFF = -6V; Ta = 25℃)

1 DC/DC CONVERTER CONTROLLER BLOCK

Parameter Symbol

[ ERROR AMPLIFIER BLOCK ]

FB Input Bias Current IFB - 0.1 - µA

Feed Back Voltage VFB 1.221 1.233 1.245 V Buffer, No load

Comp Sink Current Ioi 1 5 10 µA VFB=1.5V VCOMP=0.5V

Comp Source Current Ioo -10 -5 -1 µA VFB=1.0V VCOMP=0.5V

[ LX BLOCK ]

LX ON-Resistance Ron - 200 - mΩ

LX Leak Current Ileak - 0 10 µA VLX=18V

MAX Duty Cycle DMAX - 90 - %

LX Current Limit ILX 2.5 - - A

[ INTERNAL SOFT START BLOCK ]

Soft Start Delay Time tss - 3.25 - ms

2. GATE-ON LINEAR REGULATOR CONTROLLER

Parameter Symbol

FBP Voltage VFBP 1.225 1.25 1.275

FBP Input Bias Current IFBP - 0.1 -

DRVP Current Limit IDRVP 1 5 10

3. GATE-OFF LINEAR REGULATOR CONTROLLER

Parameter Symbol

FBN Voltage VFBN 0.235 0.25 0.265 V

FBN Input Bias Current IFBN - 0.1 - µA

DRVN Current Limit IDRVN 1 5 10 mA

4. OPERATIONAL AMPLIFIERS

Parameter Symbol

Input Offset Voltage Voff - 0 - mV VPOS1～5 = 6V

Input Range VRANGE 0 VSUP V

DRIVE Current Idrv 50 - - mA

Slew Rate SR - 40 - V/us

5. GATE SHADING CONTROLLER BLOCK

Parameter Symbol

DEL Start Period tdd - 15 - ms

DEL Source Current Idls -8 -5 -2 µA

DEL Threshold Voltage Vdls 1.2 1.25 1.3 V

CTL Input Low Voltage Vctll - - VIN x 0.3 V

CTL Input High Voltage Vchlh VIN x 0.7 - - V

CTL Input Current Ictl 8 16.5 25 µA VCTL=3.3V

SRC ON Resistance RonSRC - 5 - Ω

DRN ON Resistance RonDRV - 30 - Ω

This product is not designed for protection against radioactive rays.

Min. Typ. Max.

Limit

Unit Conditions

V

µA

mA

Unit Conditions

Technical Note

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2/12

2009.07 - Rev.B

BD8179MUV

●Electrical Characteristics (Unless otherwise specified, VIN = 3.3V; VSUP = 12 V; VGON = 25 V; VGOFF = -6V; Ta = 25℃)

6. WHOLE DEVICE

Parameter Symbol

[ REFERENCE BLOCK ]

Reference Voltage VREF 1.231 1.25 1.269 V

[ OSCILLATION BLOCK ]

Oscillation Frequency FOSC 1020 1200 1380 kHz

[ VIN UNDER VOLTAGE LOCK OUT BLOCK ]

Detect Voltage Vuvlo 2.25 2.4 2.55 V

[ SUP OVER VOLTAGE LOCK OUT BLOCK ]

Detect Voltage Vovp 18 19 20 V

[ SHORT CURRENT PROTECTION BLOCK ]

Fault Delay Time Tscp - 150 - ms

[ DETECTOR BLOCK ]

VFB OFF Threshold Voltage Vthfb 0.9 1.0 1.1 V

VFBP OFF Threshold Voltage Vthfbp 0.9 1.0 1.1 V

VFBN OFF Threshold Voltage Vthfpn 0.4 0.5 0.6 V

This product is not designed for protection against radio active rays.

Min. Typ. Max.

Limit

Unit Conditions

Technical Note

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3/12

2009.07 - Rev.B

BD8179MUV

●Reference Data (Unless otherwise specified, Ta = 25℃, VIN=5V)

Technical Note

3

2.5

2

1.5

IIN (mA)

1

0.5

0

01234567

VIN (V)

Fig.1 Supply Current

(No switching)

94

92

90

88

86

84

efficency[%]

82

80

78

76

0 100 200 30 0 400 500

Io[mA]

Fig.4 Efficiency vs Output Current

(VMAIN)

1

0.8

0.6

0.4

0.2

0

VGH[%]

0 20 40 60 80 100

⊿

-0.2

-0.4

-0.6

-0.8

-1

Io[mA]

2

1.5

1

Frequency[MHz]

0.5

0

-40 10 60

Ta[℃]

Fig.2 Switching Frequency

vs Temperature

1

0.8

0.6

0.4

0.2

0

0 100 200 300 400 500

⊿VMAIN[%]

-0.2

-0.4

-0.6

-0.8

-1

Io[mA]

Fig.5 VMAIN Voltage

Load Regulation

1

0.8

0.6

0.4

0.2

0

VGL[%]

0 20406080100

⊿

-0.2

-0.4

-0.6

-0.8

-1

Io[mA]

1000

100

10

DELAY TIME [ms]

1

0.1

0.001 0.01 0.1 1

DEL CAPACIT OR [uF]

Fig.3 Delay Time

vs Capacitor

VIMAIN

LX

Fig.6 Over Voltage Protect

waveform

COM

CTL

Fig.7 Gate-ON Voltage

Load Regulation

IN

Fig.10 AMP Slew Rate

OUT

300Ω

100pF

OUT

(Rise)

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Fig.8 Gate-OFF Voltage

Load Regulation

IN OUT

IN

300Ω

100pF

Fig.11 AMP Slew Rate

(Fall)

4/12

Fig.9 Gate Shading Output

waveform

OUT

Fig.12 Start Up Sequence

waveform

2009.07 - Rev.B