Datasheet BA9755S Datasheet (ROHM)

1

Multimedia ICs

High voltage controller for CRT
displays

BA9755S

The BA9755S is an LSI chip with a chopper voltage controller designed to control the anode voltage of multiscan
monitors and other CRTs. There are two internal high-precision power supplies, each with an output voltage preci­sion of ±1%. Using a high-precision voltage detection resistor makes it possible to set anode voltage without adjust­ment. Other internal components include an output voltage error detector and an overcurrent detector, which detects
overcurrent when the power is turned on.

•

Applications

CRT displays and HDTV products

•

Features

1) Internal chopper voltage controller.

2) Two internal high-precision power supplies, each
with an output voltage precision of ±1%.

3) Internal output voltage error detector.

4) Internal buffer circuit that directly drives power MOS­FET for output drive.

•

Absolute maximum ratings (Ta = 25°C)

•

Recommended operating voltage (Ta = 25°C)

Parameter Symbol Limits Unit

Applied voltage 1

V

CC118

∗

1

V

Applied voltage 2

V

CC220

∗

2

V

Power dissipation

Pd 600

∗

1

mW

Operating temperature

Topr – 25 ~ + 75 °C

Storage temperature

Tstg – 55 ~ + 125 °C

∗

3 Reduced by 6.0mW for each increase in Ta of 1°C over 25°C.

∗

1 18pin ∗ 2 3pin

Parameter Symbol Limits Unit

Applied voltage 1 V

CC111 ~ 13 V

Applied voltage 2 V

CC211 ~ 16 V

∗

Used with condition

V

CC2 ⭌ VCC1

2

Multimedia ICs BA9755S

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Block diagram

1

2

3

4

5

6

7

8

9

18

17

16

15

14

13

12

11

10

PROTOUT

VREG9

VREG6

XREF

XRAYIN

ABLIN

PONDET

ERROUT

GND

PWMOUT

HDIN

MMCR

SAWOUT

AGC

ERRIN

ERRREF

+

–

SAW
GEN.

AGC
TYPE

+

–

REF

9.0V

REF

6.0V

+

–

LATCH

+

–

GND

Buffer

START

M. M.

PV

CC

Power VCC

VCC

Sig VCC

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Multimedia ICs BA9755S

Pin No.

Pin name

1

GND

Ground
This is the common ground for the small signal system and the power system, and so requires
a stable ground suitable for common impedance.

2

PWMOUT

PWM wave output
Output is fixed at the low level when the protector circuit or thermal shutdown circuit is activated.

3

PV

CC

Power supply for the power system. Place a decoupling capacitor in proximity to this pin.

4

HDIN

HD pulse input. The input signal should be shorter than the rise time (

µs).

5

MMCR

Shifts the phase of the serrated wave. Use a charge resistance higher than 4.7kΩ.

Internal mono-multi time constant setting.

6

SAWOUT

f

Max. 80kHz→C = 1500p, fMax. 60kHz→C = 2000p

7

AGC

Set capacity according to the linearity of the minimum oscillation frequency and the response
time during frequency change.

AGC time constant setting.

8

ERRIN

Input of the error amplifiers feedback voltage.

9

ERRREF

Input of the error amplifiers feedback voltage.
When this voltage is given a time constant, the IC soft-starts when the power is turned on.

10

ERROUT

Output of the error detection voltage.

11

PON DET

12

ABLIN

Beam protector input. When the protector is activated, the latch locks and PWM output is fixed
at the low level.

13

XRAYIN

X-ray protector input. When the protector is activated, the latch locks and PWM output is fixed
at the low level.

14

XREF

Input of the X-ray protector's reference voltage.

15

VREG6

Reference voltage output (6V). Output variation is guaranteed to be 1% or less (with trimming).
This circuit is completely separate from the 9V system. Output is stopped when the thermal
shutdown circuit is activated. Use a 47

µF bypass capacitor.

16

VREG9

Reference voltage output (9V). Output variation is guaranteed to be 1% or less (with trimming).
This circuit is completely separate from the 6V system. Output is stopped when the thermal
shutdown circuit is activated. Use a 10

µF bypass capacitor.

17

PROTOUT

Protector output.
Output changes to the high level when the protector circuit or thermal shutdown circuit is activated.

18

Power supply for the signal system.
Place a decoupling capacitor in proximity to this pin.

Function

Serrated wave output. Adjust maximum capacity by changing maximum oscillation frequency.

V

CC

Setting the time constant for the protector output suppression time and input of the beam
protectors reference voltage. This stops the protectors until the system stabilizes. The latch
can be unlocked by raising the voltage of this pin above 4.5V.

f

Max. 120kHz→C = 1000p, fMax. 100kHz→C = 1200p

•

Pin descriptions

4

Multimedia ICs BA9755S

•

Input / output circuits

GND

11k

2k

V

CC

PMWOUT

PVCC

HDIN

37.5k

37.5k

75k

75k

50k

VCC

MMCR

SAWOUT

AGC

5k

1k

3.5k

4k

330k

30k

2k 4k

7.5k

22.5k

VCC

VCC

9

ERRIN

ERRREF

1k

1k

VCC

ERROUT

2k

2k 2k

20k

5p

Ref 6V

13k

150

150

1 2 3

4

5

6 7

109

8

5

Multimedia ICs BA9755S

12

PONDET

ABLIN

10k

50k

4k

1k 1k

4k

VCC

1k 1k

4k

XRAYIN

XREF

1k

25k

20

R23

74.45k

1960

960

20.01k

295

590

50

VREG6

1k

25k

VREG9

200

144

10.01k

760

61.335k

55

20k

50k

PROTOUT

1k

380

20k

Ref 6V

ESD16

VCC

VCC

VCC

VCC

VCC

11 12 13 14

15

16

17

18

6

Multimedia ICs BA9755S

Parameter Symbol Min. Typ. Max. Unit

Supply current I

CC — 13 21 mA S6 = 2

Input bias current I

B — – 45 – 250 nA

Input offset voltage V

IO — ± 1 ± 5 mV S9b, 9c = 3 ; VIO = V10 × 10

– 2

VOL 0 0.2 0.5 V S9a, 9c = 2 ; Vs9 = 6V
V

OH 10 10.5 — V S9a, 9c = 2 ; Vs9 = 4V

Open loop gain Av 50 60 — dB f = 1kHz, guaranteed performance
Maximum output current I

OM ± 3 ± 5 ± 7 mA S10 = 2 ; Vs10 = 12V, 0V

〈 Protector 〉

Input bias current I

B — 0 – 50 nA Vs11, 12, 13, 14 = 0V

Input offset voltage V

IO — ± 1 ± 5mV

Common mode input voltage V

ICR 0 — 10 V

Output voltage, High V

OH 10.0 11.0 — V S17 = 2 ; Vs12 = 5V ; Is17 = – 50µA

Output voltage, Low V

OL — 1.0 2.0 V S17 = 2 ; Is17 = 3mA

Output voltage, High level V

OH 9.5 10.5 — VS2 = 2 ; Is2 = – 100mA

Output voltage, Low level V

OL — 12VS2 = 2 ; Vs8 = 3V ; Is2 = 100mA

Rise time T

r ——60 ns Guaranteed performance

Fall time T

d ——40 ns Guaranteed performance

Minimum pulse width

T

Min. 0.5 — 1.3 µs

S4 = 2 ; Vs8 = 0V ; SG4 = p1 (f = 90kHz) ; threshold = 5V

Input voltage, High level V

IH 4.0 — Vcc V Verify oscillation of SAW GEN. S4 = 2 ; Vs8 = 0V ; SG4 = p1

Input voltage, Low level V

IL ——1.5 V Verify oscillation of SAW GEN. S4 = 2 ; Vs8 = 0V ; SG4 = p1

Input current, High level I

OH — 285 420 µA Vs4 = 12V

Input current, Low level I

OL ——0 – 1 µA

Delay time T

dl 0.3 0.5 0.8 µs

H

OS 8.0 9.0 10.0 V

L

OS 0 0.15 0.35 V

Output frequency characteritic

FSAW 150 200 — kHz

Output voltage V

REF9 8.91 9.0 9.09 V

Maximum output current I

RMax. 10 ——mA S15 = 2 ; Is = 10mA ;

Output voltage
temperature characteristics

T

VREF – 0.7 — 0.7 % Ta = – 25°C ~ + 75°C

Output voltage V

REF6 5.94 6.0 6.06 V

Max. output current I

RMax. 10 —

—

—

— mA S15 = 2 ; Is = 10mA ;

Output voltage
temp. characteristics

T

VREF – 0.7 — 0.7 % Ta = – 25°C ~ + 75°C

Thermal shutdown

T

dow 100 —— —deg

Output voltage, Low
Output voltage, High

Output level, Low

Output level, High

∗

1 Time between rise of pin 4 input waveform and rise of pin 2 output waveform

Conditions

S4 = 2 ; Vs8 = 0V ; SG4 = p1
; (R = 4.7kΩ, C = 0pF)

∗

1

Verify: pin 17 = LO→HI when Vs12 = 6.005V→5.995V
Verify: pin 17 = LO→HI when Vs13 = 5.995V→6.005V

Verify: pin 17 = LO when Vs13 (Vs14 = Vs13 + 0.5V) = 0, 10V

Verify: pin 17 = LO when Vs11 (Vs12 = Vs11 + 0.5V) = 0, 10V

HI level of S4 = 2 ; SG4 = p1 ; 6pin output wave form
LO level of S4 = 2 ; SG4 = p1 ; 6pin output wave form
S4 = 2, SG4 = input frequency 1 dB lower than

HI level of pin 6 output waveform when SG4 = p2

S8, 9a, 9b, 9c = 2 ; Vs8, 9 = 0V
; I

B8 (IB9) = V8 (V9) × 10

– 5

〈 Error amplifier 〉

〈 PWM amplifier 〉

〈 Hd input pin 〉

〈 Monomulti 〉

〈 SAW GEN 〉

〈

Reference voltage source 1

〉

〈

Reference voltage source 2

〉

•

Electrical characteristics (unless otherwise noted, Ta = 25°C, VCC = 12V)

7

Multimedia ICs BA9755S

1 23456789

18 17 16 15 14 13 12 11 10

+

–

+–

REF

9.0V

+

–

LATCH

+

–

GND

START

S2

1

2

1

S2

V

12

V A

S4

SG4

V

S4

V

9V

4.7k
1200p

V

1

2

VS6 4V

S6

V

VS8

5V

1µ

2

1
S8
50

100k

100k

1

S9b

VS9

50

3

2

1 32

S9a

S9c

1

2

A

V

1

2

S17

I

S17

V

CC

V

1

2

S16

I

S16

15mA

+

V

1

2

15mA

+

A

A

S15

I

S15

6V
V

S14

A

6V

A

A

A

5V 7V
V

S13 VS12 VS11

V

1

2

A

Is10

S10

5k

M. M.

REF

6.0V

SAW GEN.

AGC TYPE

Power

VCC

Sig VCC

Universal

counter

Peak

voltmeter

Universal

counter

4V

V V

Fig. 1

•

Measurement circuit

SG4 input pulse

4.0V

1.5V
5µs

11µs

4.0V

1.5V
5µs

p1

p2

33µs

8

Multimedia ICs BA9755S

•

Application example

1 23456789

18 17 16 15 14 13 12 11 10

+

–

+–

+

–

LATCH

+

–

GND

START

Buffer

+

12V

+

+

+

+B

Hd

HRC

FBT

VCC 12V

M. M.

SAW GEN.
AGC TYPE

Power V

CC

Sig VCC

Anode Voltage

PROT OUT

REF

9.0V

REF

6.0V

Hd pulse

Fig. 2

9

Multimedia ICs BA9755S

•

Electrical characteristic curves

0 50 100 150 200 250

1

2

3

4

5

HIGH LEVEL OUTPUT VOLTAGE : VOH (V)

OUTPUT CURRENT : IO (mA)

Fig. 3 PWM HIGH output voltage vs.

output current

– 50 – 100 – 150 – 200 – 250

8

10

11

12

0

7

9

LOW LEVEL OUTPUT VOLTAGE : VOL (V)

OUTPUT CURRENT : IO (mA)

Fig. 4 PWM LOW output voltage vs.

output current

– 50 – 25 0 + 25 + 50 + 75 + 100

0.4

0.5

0.6

0.7

0.8

0.9

1.0

1.1

1.2

1.3

TEMPERATURE : Ta (°C)

PWM Min. PULSE WIDTH : TMin. (µs)

Fig. 5 PWM minimum pulse width vs.

temperature

– 50 – 25 0 + 25 + 50 + 75 + 100

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0.3

0.2

0.1

PWM Min. DELAY TIME : Tdl (µs)

TEMPERATURE : Ta (°C)

Fig. 6 PWM minimum delay time vs.

temperature

6.10

6.08

6.06

6.04

6.02

6.00

5.98

5.96

5.94

– 50 – 25 0 + 25 + 50 + 75 + 100

5.92

OUTPUT VOLTAGE : VREF 6 (V)

TEMPERATURE : Ta (°C)

Fig. 7 Output voltage

(6V reference voltage) vs.
temperature

– 50 – 25 0 + 25 + 50 + 75 + 100

9.08

9.06

9.04

9.02

9.00

8.98

8.96

8.94

8.92

8.90

OUTPUT VOLTAGE : VREF9 (V)

TEMPERATURE : Ta (°C)

Fig. 8 Output voltage
(9V reference voltage) vs.

temperature

9.6

9.4

9.2

9.0

8.8

8.6

8.4

8.2

8.0

7.8

10 20 30 50 70 100 200 300

SAW OUT HIGH PEAK LEVEL : HOS (V)

FREQUENCY : f (kHz)

Fig. 9 SAW H peak vs.

frequency

10

Multimedia ICs BA9755S

SDIP18

0.51Min.

0° ~ 15°

7.62

3.95 ± 0.3

1.778

10

9

6.5 ± 0.3

19.4 ± 0.3

18

1

0.5 ± 0.1

3.4 ± 0.2

0.3 ± 0.1

•

External dimensions (Units: mm)