Полупроводники. Каталог (2011 год)

WT8045

Synchronous Signal Discriminator and

Power Saving Detector for Green Monitor



Weltrend Semiconductor, Inc.

2F., No. 24, Industry E. 9th Rd.

Science-Based Industrial Park

Hsin-Chu, Taiwan, R.O.C.

Tel: 886-35-780241

Fax: 886-35-770419

MONO_STABLE DYNAMIC ELECTRICAL CHARACTERISTICS

(Ta=25

C; Input tr,tf=20ns, CL=50PF)

ITEM

MIN.

TYP.

MAX.

UNITS

Input H_SYNC Pulse Width

0.558

¡ Ð

£ g

Input V_SYNC Pulse Width

0.0384

¡ Ð

0.125

Output Pulse Transition Time

¡ Ð

100

200

Output Pulse Propagation Delay

¡ Ð

300

600

Output Pulse Width Adjust Range

¡ Ð

¢ M

H_MONO_STB:

31KHz

¡ Ð

37.5KHz

26.66

£ g

31KHz

¡ Ð

48KHz

20.83

£ g

31KHz

¡ Ð

57KHz

17.54

£ g

31KHz

¡ Ð

64KHz

15.62

£ g

V_MONO_STB:

(50Hz

¡ Ð

120Hz)*128

6.4KHz

¡ Ð

15.36KHz

65.10

£ g

(50Hz

¡ Ð

80Hz)*128

6.4KHz

¡ Ð

10.2KHz

97.66

£ g

(50Hz

¡ Ð

120Hz)*1

Typical Pulse width Variation as a
function of Temperature at 75

¢ J

¡ Ð

¡ Ó

¢ M

Typical Pulse Width Variation as a
function of Supply Voltage at
4.75V to 5.25V

¡ Ð

¡ Ó

¢ M

Output Low (Sink) Current

¡ Ð

Output Voltage Low-Level

¡ Ð

0.05

Output Voltage High-Level

4.95

¡ Ð

Output Jitter (Hout & Vout)

Hin & Vin Rise time and Fall time = 200ns

WT8045

Synchronous Signal Discriminator and

Power Saving Detector for Green Monitor



Weltrend Semiconductor, Inc.

2F., No. 24, Industry E. 9th Rd.

Science-Based Industrial Park

Hsin-Chu, Taiwan, R.O.C.

Tel: 886-35-780241

Fax: 886-35-770419

APPLICATION INFORMATION

Struncure

Name

Function

Terminal

OSCin

A clock generating circuit is built into the chip. So if a resonator is
connected to OSCin/OSCout, a clock signal can be obtained

OSCout

Refer to OSCin pin

Hsin

Input terminal of horizontal synchronous signal

I, TTL

compatible

Vsin

Input terminal of vertical synchronous signal

I, TTL

compatible

H_OUT

Output pin, fixed negative polarity of original H_SYNC signal with
same pulse width (but, positive for N28P2, N28P6,N28P7 and
N28P8)

I, TTL

compatible

V_OUT

Output pin, fixed negative polarity of original V_SYNC signal with
same pulse width (but, positive for N28P2, N28P6,N28P7 and
N28P8)

O, TTL

compatible

F43.5k

>43.5k then active low, <43.5k then high

O, open drain

F36.2k

>36.2k then active low, <36.2k then high

O, open drain

F33k

>33k then active low, <33k then high

O, open drain

Output pin, fixed positive polarity of vertical signal; pulse width
depend upon RV & CV.

O, open drain

QVRC

Input pin, connected to Vdd through RV & to ground through CV I

Vss

Ground

SELPIN

Input pin, to select which one of H_SYNC or V_SYNC appears on
the output pin of QV; N.C. selects the V-SYNC on the output,
grounding selects the H_SYNC.

(N.C.-no
connection)

-QH

Output pin, fixed negative polarity of horizontal signal; pulse width
depend upon RH & CH.

O, open drain

F52k

>52k then active low, <52k then high

O, open drain

F60k

>60k then active low, < 60k then high

O, open drain

PM1

Indicate in STAND-BY mode

O, open drain

WT8045

Synchronous Signal Discriminator and

Power Saving Detector for Green Monitor



Weltrend Semiconductor, Inc.

2F., No. 24, Industry E. 9th Rd.

Science-Based Industrial Park

Hsin-Chu, Taiwan, R.O.C.

Tel: 886-35-780241

Fax: 886-35-770419

Struncure

Name

Function

Terminal

PM2

Indicate in SUSPEND mode

O, open drain

PM3

Indicate in OFF mode

O, open drain

QHRC

Input pin, connected to Vdd through RH & to ground through CH.

Output pin, fixed positive polarity of horizontal signal; pulse width
depend upon RH & CH

O, open drain

640

¡ Ñ

350

Mode select control output, if IBM VGA 640

¡ Ñ

350 mode, or VESA

VGA 640

¡ Ñ

350 mode. Then active "low", else open state output

O, open drain

640

¡ Ñ

480

VESA VGA mode 640

¡ Ñ

480 (37.5k/72Hz)

O, open drain

640

¡ Ñ

400

If IBM VGA 640

¡ Ñ

400 mode, or VESA VGA 640

¡ Ñ

400 mode then

active "low" (640

¡ Ñ

400, 31.5k, for N24P4)

O, open drain

640

¡ Ñ

480

If IBM VGA 640

¡ Ñ

480 mode, or VESA VGA 640

¡ Ñ

480 mode then

active "low" (640

¡ Ñ

480, 31.5k, for N24P4)

O, open drain

800

¡ Ñ

600

VESA super VGA mode

(H_SYNC = 35.2k, V_SYNC = 56Hz)

O, open drain

800

¡ Ñ

600

European super VGA mode

(H_SYNC = 37.5k, V_SYNC = 60Hz)

O, open drain

800

¡ Ñ

600

VESA new super VGA mode

(H_SYNC = 48k, V_SYNC = 72Hz)

O, open drain

1024

¡ Ñ

768(I)

IBM 8512/A interlace mode

(H_SYNC = 35.5k, V_SYNC = 86Hz)

O, open drain

1280

¡ Ñ

1024

1280

¡ Ñ

1024 mode control output

(H_SYNC = 64k, V_SYNC = 60Hz)

O, open drain

1024

¡ Ñ

768(NI)

IBM 8514/A non-interlace mode

(H_SYNC = 48.5k, V_SYNC = 60Hz)

O, open drain

1024

¡ Ñ

768(57k)

XGA 1024

¡ Ñ

768 mode Hsync freq. 57kHz

(H_SYNC = 56.5k, V_SYNC = 72Hz)

O, open drain

Vdd

5 Volts power supply

WT8045

Synchronous Signal Discriminator and

Power Saving Detector for Green Monitor



Weltrend Semiconductor, Inc.

2F., No. 24, Industry E. 9th Rd.

Science-Based Industrial Park

Hsin-Chu, Taiwan, R.O.C.

Tel: 886-35-780241

Fax: 886-35-770419

APPLICATION DESCRIPTION

DPMS (Display Power Management Signaling) Detection

As per DPMS proposal version 1.0P, revision 0.54P, WT8045 provides Monitor Power
Management Detection Circuit for the convenience of monitor designers in designing power
saving monitors, or the so called "Green Monitors". Please refer to the table 1 as below for
power states defined in the DPMS.

DPMS requires at least 5 seconds delay before transition from ON state to any power saving
state, to avoid unintentionally entering a power saving state during display resolution changes
and timing mode changes. And it can be done instantaneously, for the transition between any
power saving state.

Table 1 Display Power Management Summary

State

Signals

DPMS

Compliance

Power

Savings

Recovery

Time

Horizontal

Vertical

Video

Requirement

Pulses

Active

Mandatory

None

Not

Applicable

Stand-by

No Pulses

Pulses

Blanked

Optional

Minimal

Short

Suspend

Pulses

No Pulses Blanked

Mandatory

Substantial

Longer

Off

No Pulses No Pulses Blanked

Mandatory

Maximum

System

Dependent

"No-Pulse" represents the frequency of Hsin or Vsin less than or equal to 10Hz, but
"Pulses" represents that frequency of Hsin greater than or equal to 10KHz and Vsin
greater than or equal to 40Hz

WT8045

Synchronous Signal Discriminator and

Power Saving Detector for Green Monitor



Weltrend Semiconductor, Inc.

2F., No. 24, Industry E. 9th Rd.

Science-Based Industrial Park

Hsin-Chu, Taiwan, R.O.C.

Tel: 886-35-780241

Fax: 886-35-770419

The way WT8045 implements VESA DPMS

As shown on Table 2, WT8045 use PM1 to represent Stand-by State, PM2 as Suspend State and
PM3 as OFF State. When H_SYNC / V_SYNC signals transition from ON State to any one of
the three power saving states, WT8045 will delay 5.9 seconds to meet the VESA DPMS
requirement: the minimum 5 seconds delay to avoid unintentionally entering a power saving
state during display resolution and timing mode changes. If during this delay time period,
H_SYN and V_SYN signals return to ON State, then all three power management pins (PM1,
PM2 and PM3) will remain ON state. If power management state of H_SYNC and V_SYNC
prolong for more than 5.9 seconds, then these three power management pins will change to the
corresponding states. While changing from any power saving state back to ON State will take
about 0.368 second for H_SYNC / VSYNC pulse checking. And transition between any power
saving state will be done immediately.

Table 2: The truth table of Power Saving Detector

MODE

Hsin

Vsin

PM1

PM2

PM3

Pulses

STAND_BY

No Pulses

Pulses

SUSPEND

Pulses

No Pulses

OFF

No Pulses

OVERRIDE

No Pulses

Manually PWR ON

OVERRIDE mode:

To initial override, both horizontal and vertical sync signals shall be in the no pulses condition
when the display is maintained during the entire time override is required. As soon as pulses are
detected on horizontal and vertical sync signal. The display shall enter DPMS operation.

Three power management pins are open drain structure and active low. If you do not need all
those three power saving states in your design. You can just short two or three pins of the pins
PM1/PM2/PM3. for example, by shorting pin PM1 and pin PM2, you will have only two power
saving states, that is OFF and Suspend states, so you have three states total, including ON State.
Please refer to Application Circuit 2.

WT8045

Synchronous Signal Discriminator and

Power Saving Detector for Green Monitor



Weltrend Semiconductor, Inc.

2F., No. 24, Industry E. 9th Rd.

Science-Based Industrial Park

Hsin-Chu, Taiwan, R.O.C.

Tel: 886-35-780241

Fax: 886-35-770419

Mono_Stable Circuit

WT8045 includes two sets of Mono_Stable Circuits, one uses H_SYNC as trigger signal, the
other uses either H_SYNC or V_SYNC as trigger signal (this only can be done on 32 pin
package, for 24 pin and 28 pin packages the trigger signal is fixed to H_SYNC); for N24p4
package, there is no mono-stable circuit. Please refer to the figure as below:

H-SYNC

V-SYNC

SELECT

SWITCH

vcc

Rx/Cx

QH-

vcc

Rx/Cx

Q-

SELECT=OPEN

SELECT=L

The Mono_Stable Circuit is triggered by positive edge, no matter H_SYNC or V_SYNC is used
as trigger signal. Please refer to the timing chart as below:

Trigger Pulse

Q-

positive

negative

The output of Mono_Stable Circuit is open drain structure, and can be pulled up to +12V
maximum.

WT8045

Synchronous Signal Discriminator and

Power Saving Detector for Green Monitor



Weltrend Semiconductor, Inc.

2F., No. 24, Industry E. 9th Rd.

Science-Based Industrial Park

Hsin-Chu, Taiwan, R.O.C.

Tel: 886-35-780241

Fax: 886-35-770419

In case of using output pulse of V_MONO_STABLE as voltage source, in order to prevent the
problem of slow response time, causing from the low frequency on vertical synchronous signal,
WT8045 internally increases the vertical signal frequency to 128 times the original frequency,
that is from 50Hz - 120 Hz to 6.4KHz - 15.36KHz. Then WT8045 uses this increased frequency
as the input signal of MONO_STABLE, so the leading edge of the signal of the increased
frequency will trigger the MONO_STABLE circuit.

An external resistor (Rx) and an external capacitor (Cx) control the timing and accuracy of the
circuit. Adjustment of Rx and Cx provides a wide range of output pulse widths from the Q and
Q-bar terminals. The delay time from trigger input to output transition is independent of Rx and
Cx.

The minimum value of external resistor Rx is 10k ohms. The typical value of external capacitor
Cx is 100 pF. The time period (T) for this multi-vibrator can be calculated with the formula: T

≈

1.1 Rx

•

Cx.

H/V Frequency Divisions and Video Modes

Figure 1 illustrates the typical frequency ranges of H and V sync signals for display monitors.
The operating video modes are determined by the H and V frequencies, and occasionally, by
their polarities. The typical video modes of display monitors include the IBM VGA, VESA VGA,
European VGA/super VGA, VESA super VGA, IBM 8514/A, XGA, and 1280x 1024.

WT8045 can determine 13 standard video modes for 32 pin package (refer to Table 3) according
to H and V frequencies and polarities. These standard video modes include the IBM VGA,
VESA VGA, VESA super VGA and IBM 8514/A. This provides the users with the capability to
adjust the screen size for different modes.

WT8045 pre-sets the discriminating points both on H and V frequencies. The discriminating
points for H sync are 33KHz, 36.2KHz, 43.5KHz, 52KHz and 60KHz (for 32 pin). These
discriminating points will be able to identify various video modes as shown in Fig. 1. WT8045
also provides the flexibility for users to define these discriminating points through mask option.

WT8045

Synchronous Signal Discriminator and

Power Saving Detector for Green Monitor



Weltrend Semiconductor, Inc.

2F., No. 24, Industry E. 9th Rd.

Science-Based Industrial Park

Hsin-Chu, Taiwan, R.O.C.

Tel: 886-35-780241

Fax: 886-35-770419

The tolerance for H sync frequency discrimination is

¡ Ó

0.1KHz. For instance, the 33KHz

discriminating point will be able to distinguish the H sync frequency that is either "less than or
equal to" 32.9KHz, or "greater than or equal to" 33.1KHz. There is an ambiguous region
between 32.9KHz and 33.1KHz.

WT8045 has two discriminating points, 64Hz and 78Hz, for the V sync signal as shown in Fig.1.
The tolerance is

¡ Ó

0.4Hz. The discrimination results of V sync frequency are used internally for

mode selection.

Base on the package consideration, IBM VGA mode and VESA VGA mode (both have same
resolution: 640x480, 640x400, 640x350) are decoded on same open Drain structure output pins.
In case of these whole six modes decoding is needed, the horizontal frequency discrimination pin
F33k or F36.2k must take into consideration. The horizontal frequency of IBM VGA mode is
31.5kHz, and VESA IBM VGA mode is 37.5kHz. Using F33k or F36.2k pin can clearly identify
these two standard modes. The decoding circuit is attached on application section for reference.

Graphic Standard

Resolution

Horizontal

Vertical

Polarities

640X350

31.5kHz

70Hz

+,-

IBM VGA

640X400

31.5kHz

70Hz

-,+

640X480

31.5kHz

60Hz

-.-

VESA Super VGA

800X600

35.2kHz

56Hz

IBM 8512/A Interlaced

1024X768

35.5kHz

86Hz

640X350

37.5kHz

83Hz

+,-

VESA VGA

640X400

37.5kHz

83Hz

-,+

640X480

37.5kHz

72Hz

-,-

European Super VGA

800X600

37.5kHz

60Hz

VESA New Super VGA

800X600

48.0kHz

72Hz

IBM 8514/A Non-Interlaced

1024X768

48.5kHz

60Hz

VESA New 1024X768

1024X768

56.5kHz

72Hz

Work Station 1280X1024

1280X1024

64.0kHz

60Hz

Table 3: Graphic Standard and Frequencies

WT8045

Synchronous Signal Discriminator and

Power Saving Detector for Green Monitor



Weltrend Semiconductor, Inc.

2F., No. 24, Industry E. 9th Rd.

Science-Based Industrial Park

Hsin-Chu, Taiwan, R.O.C.

Tel: 886-35-780241

Fax: 886-35-770419

640X350

(+,-)

640x400

(-,+)

1024X768

640X350

(+,-)

640x400

(-,+)

640X480

(-,-)

640X480

(-,-)

1024X768

800X600

1280X1024

Fv (Hz)

83.86

70.72

56.60

31.5

36.2

43.5

60
(58.5 for N28P2)

Fh(KHz)

Figure 1: H/V Frequency Division and Video Mode

640X480

640X400

640X350

Mode

IBM

640X480

640X400

VGA

640X350

VESA

640X480

640X400

VGA

640X350

Table 4: IBM VGA/ VESA VGA Decoding Table

WT8045

Synchronous Signal Discriminator and

Power Saving Detector for Green Monitor



Weltrend Semiconductor, Inc.

2F., No. 24, Industry E. 9th Rd.

Science-Based Industrial Park

Hsin-Chu, Taiwan, R.O.C.

Tel: 886-35-780241

Fax: 886-35-770419

Horizontal Frequency Discriminator

There are horizontal frequency discriminator pins on different type package: 33k, 36.2k (for
N24P4 package); 33k, 36.2k, 43.5k (for 24 pin); 33k, 36.2k, 43.5k, 52k (for 28 pin); 33k, 36.2k,
43.5k, 52k, 60k (for 32 pin); please refer to table 5 for the logical truth table of these pins. These
frequency discriminator pins output can be used for CS Capacitor Control directly as well as
other application.

Signa
l
Hsync

F33k

F36k

F43.5k

F52k

F60k

Hs<33k

36k>Hs>33k

43.5k>Hs>36k

52k>Hs>43.5k

60k>Hs>52k

Table 5: Truth table of Frequency discriminator

Mute function Timing Diagram

WT8045

Synchronous Signal Discriminator and

Power Saving Detector for Green Monitor



Weltrend Semiconductor, Inc.

2F., No. 24, Industry E. 9th Rd.

Science-Based Industrial Park

Hsin-Chu, Taiwan, R.O.C.

Tel: 886-35-780241

Fax: 886-35-770419

DIP OUTLINE DIMENSIONS

N24

1250

542

152

100

130

650

600

N28

SKINNY

1385

288

130

100

130

355

310

N32

1650

542

154

100

130

650

600

¡ ¯

Dimension in mil

¡ ¯

1mm = 39.37 mil

Полупроводники. Каталог (2011 год) - часть 11