The NTE7133 is an integrated circuit in a 20–Lead DIP type package. This device is designed to provide an economical solution in VGA/XGA and autosync monitors by incorporating complete horizontal and vertical small signal processing. VGA–dependent mode detection and setting are performed
on–chip.
Features:
DVGA Operation Fully Implemented Including Alignment–Free Vertical and E/W Amplitude
Pre–Settings
D4th VGA Mode Easy Applicable (XGA, Super VGA)
DAutosync Operation Externally Selectable
DLow Jitter
DAll Adjustments DC–Controllable
DAlignment–Free Oscillators
DSync Separators for Video or Horizontal and Vertical TTL Sync Levels Regardless or Polarity
DHorizontal Oscillator with P
DConstant Vertical and E/W Amplitude in Multi–Frequency Operation
DDC–Coupling to Vertical Power Amplifier
DInternal Supply Voltage Stabilization with Excellent Ripple Rejection to Ensure Stable Geometrical
Adjustments
for Sync and P
LL1
for Flyback
LL2
Absolute Maximum Ratings:
Supply Voltage (Pin1), V
Voltage (Pin3, Pin7), V3, V
Voltage (Pin8), V
8
Voltage (Pin5, Pin6, Pin9, Pin10, Pin13, Pin14, Pin18), V
Current (Pin2), I
Current (Pin3), I
Current (Pin7), I
Current (Pin8), I
2
3
7
8
Electrostatic Handling for All Pins (Note 1), V
Operating Junction Temperature, T
Operating Ambient Temperatrure Range, T
Storage Temperature Range, T
Thermal Resistance, Junction–to–Ambient (In Free Air), R
P
7
n
esd
J
A
stg
thJA
Note 1. Equivalent to discharging a 200pF capacitor through a 0Ω series resistor.
Temperature CoefficientTCTA = +20° to +100°C––±9010–6/K
Power Supply Ripple RejectionPSRRf = 1kHz Sine Wave6075–dB
f = 1MHz Sine Wave2535–dB
Supply Voltage (Pin1) to Ensure All Internal
V
P
Reference Voltages
Composite Sync Input (AC–Coupled, V10 = 5V)
Sync Amplitude of Video Input Signal (Pin9)V
i sync
Sync on Green–300–mV
Top Sync Clamping Level1.11.281.5V
Slicing Level Above Top Sync LevelSync on Green, RS = 50Ω90120150mV
Allowed Source Resistance for 7% Duty CycleR
Differential Input Resistancer
Charging Current of Coupling CapacitorI
Vertical Sync Integration Time to Generate
Vertical Free–Running Frequencyf
Nominal Vertical Sync Rangef
Voltage on Pin15V
Delay Between Sync Pulse and Start of Vertical
Scan in VGA/XGA Mode
Delay Between Sync Pulse and Start of Vertical
Scan in Autosync Mode
Control Current for Amplitude ControlI
Capacitor for Amplitude ControlC
Vertical Differential Output
Differential Output Current Between Pin5 and
Pin6 (Peak–to–Peak Value)
Maximum Offset Current ErrorIo = 1mA––±2.5%
Maximum Linearity Error––±1.5%
Vertical Amplitude Adjustment (In Percent of Output Signal)
Input VoltageV
Adjustment CurrentI
(VGA Operation Disabled)
E/W Output (Note 2)
Bottom Output Signal During Mid–Scan (Pin11)V
Top Output Signal During Flyback4.24.54.8V
Temperature Coefficient of Output SignalTC––25010–6/K
E/W Amplitude Adjustment (Parabola)
Input Voltage (Pin14)V
Adjustment CurrentI
= 6.25V)
ref
o
V
15
t
d
12
12
I
o
13
13
∆Io/∆t
11
14
14
R15 = 22kΩ, C16 = 0.1µF–42–Hz
No fo Adjustment50–110Hz
R15 = 22kΩ2.83.03.2V
Measured on Pin8,
500575650µs
Activated by an External
Resistor on Pin7
Note 2. ∆Io/∆t relative to value of Mode 3.
Note 3. Parabola amplitude tracks with mode–dependent vertical amplitude but not with vertical
amplitude adjustment. Tracking can be achieved by a resistor from ver tical am pli tude
potentiometer to Pin14.
Page 5
Functional Description:
Horizontal Sync Separator and Polarity Correction
An AC–coupled video signal or a DC–coupled TTL sync signal (H only or composite sync) is input
on Pin9. Video signals are clamped with top sync on 12.8V, and are sliced at 1.4V. This results in a
fixed absolute slicing level of 120mV relative to top sync.
DC–coupled TTL sync signals are also sliced at 1.4V, however with the clamping circuit in current limitation. The polarity of the separated sync is detected by internal integration of the signal, then the polarity is corrected.
The polarity information is fed to the VGA mode detector. The corrected sync is the input signal for
the vertical sync integrator and the P
LL1
stage.
Vertical Sync Separaztor, Polarity Correction and Vertical Sync Integrator
DC–coupled vertical TTL sync signals may be applied to Pin10. They are sliced at 1.4V. The polarity
of the separated sync is detected by internal integration, then polarity is corrected. The polarity information is fed to the VGA mode detector. If Pin10 is not used, it must be connected to GND.
The separated V
signal from Pin10, or the integrated composite sync signal from Pin9 (TTL or
i sync
video) directly triggers the vertical oscillator.
VGA Mode Detector and Mode Output
The three standard VGA modes and a 4th not fixed mode are decoded by the polarities of the horizontal and the vertical sync input signals. An external resistor (from VP to Pin7) is necessary to match
this function. In all three VGA modes the correxct amplitudes are activated. The presence of the 4th
mode is indicated by HIGH on Pin7. This signal can be used externally to switch any horizontal or
vertical parameters.
VGA Mode Detector Input
For autosync operation the voltage on Pin7 must be externally forced to a level of < 50mV. Vertical
amplitude pre–settings for VGA are then inhibited. The delay time between vertical trigger pulse and
the start of vertical deflection changes from 575 to 300µs (575µs is needed for VGA). The vertical
amplitude then remains constant in a frequency range from 50 to 110Hz.
Clamping and V–Blanking Generator
A combined clamping and V–blanking pulse is available on Pin8. The lower level of 1.9V is the blanking signal derived from the vertical blanking pulse from the internal vertical oscillator.
Vertical blanking equals the delay between vertical sync and the start of vertical scan. By this, an optimum blanking is acheived for VGA/XGA as well as for multi–frequency operation (selectable via
Pin7).
The upper level of 5.4V is the horizontal clamping pulse with internally fixed pulse width of 0.8µs. A
mono flop, which is triggered by the trailing edge of the horizontal sync pulse, generates this pulse.
If composite sync is applied one clamping pulse per H–period is generated during V–sync. The pahse
of the clamping pulse may change during V–sync.
P
Phase Detector
LL1
The phase detector is a standard one using switched current sources. The middle of the sync is
compared with a fixed point of the oscillator sawtooth voltage. The PLL filter is connected to Pin17.
If composite sync is applied, the distributed control voltage is corrected during V–sync.
Horizontal Oscillator
This oscillator is a relaxation type and requires a fixed capacitor of 10nF at Pin19. By changing the
current into Pin18 the whole frequency range from 13 to 100kHz can be covered.
The current can be generated either by a frequency to voltage converter or by a resistor. A frequency
adjustment may also be added if necessary.
The P
control voltage at Pin17 moduloates via a buffer stage the oscillator thresholds. A high DC–
LL1
loop gaqin ensures a stable phase relationship between horizontal sunc and line flyback pulses.
Page 6
Functional Description (Cont’d):
P
Phase Detector
LL2
This pahse detector is similar to the P
phase detector. Line flyback signals (Pin2) are compared
LL1
with a fixed point of the oscillator sawtooth voltage. Delays in the horizontal deflection circuit are compensated by adjusting the phase relationship between horizontal sync and horizontal output pulses.
A certain amount of phase adjustment is possible by injecting a DC current froma an external source
into the P
filter capacitor on Pin20.
LL2
Horizontal Driver
This open–collector output stage (Pin3) can directly drive an external driver transistor . The saturation
voltage is 300mV at 20mA. To protect the line deflection transistor, the horizontal output stage does
not conduct at VP < 6.4V (Pin1).
Vertical Oscillator and Amplitude Control
This stage is designed for fast stabilization of the vertical amplitude after changes in sync conditions.
The free–running frequency fo is determined by the values of R
VOS
and C
. The recommended
VOS
values should be altered marginally only to preserve the excellent linearity and noise performance.
The vertical drive currents I5 and I6 are in relation to the value of R
quency must be determined only by C
fo =
10.8 x R
1
VOS
x C
VOS
on Pin16.
VOS
. Therefore, the oscillator fre-
VOS
To acheive a stabilized amplitude the free–running frequency fo (without adjustment) must be lower
than the lowest occurring sync frequency. The contributions shown in Table 1 can be assumed.
Table 1. Calculation of fo Total Spread
Contributing Elements%
Minimum Frequency Offset Between fo and the Lowest Trigger Frequency10
Spread of IC±3
Spread of R (22kΩ)±1
Spread of C (0.1µF)±5
Total19
Results for 50 to 110Hz application: fo =
50Hz
1.19
= 42Hz
Table 2. VGA Modes
ModeHorizontal/Vertical
Sync Polarity
1+/–31.4570350LOW
2–/+31.4570400LOW
3–/–31.4560480LOW
4+/+Fixed by External Circuitry––HIGH
Autosync*/*Fixed by External Circuitry––Forced to GND
Horizontal
Frequency
(kHz)
Vertical
Frequency
(Hz)
Number of
Active Lines
Output
Mode Pin7
Page 7
Pin Connection Diagram
V
P
Horiz Flyback Input
Horiz Output
GND (0V)
Vert Output 1/Neg–Going Sawtooth
Vert Output 2/Pos–Going Sawtooth
4th Mode Output/Autosync In
Clamping/Blanking Pulse Out
Horiz Sync/Video In
Vert Sync In
1
2
3
4
5
6
7
8
20
19
18
17
16 Vert OSC Capacitor
15
14
13
1011
P
Phase
LL2
Horiz OSC Capacitor
Horiz OSC Resistor
P
Phase
LL1
Vert OSC Resistor
E/W Amp Adj Input (Parabola)
V ert Amp Adj Input
Cap for Amp Control912
E/W Output (Parabola to Driver Stage)
2011
.280 (7.12) Max
110
.995 (25.3) Max
.300 (7.62)
.280
(7.1)
.100 (2.54).125 (3.17) Min.385 (9.8)
Loading...
+ hidden pages
You need points to download manuals.
1 point = 1 manual.
You can buy points or you can get point for every manual you upload.