NJM2267

NJM2267
DUAL VIDEO 6dB AMPLIFIER WITH 75Ω DRIVER
■ GENERAL DESCRIPTION
NJM2267 is a dual video 6dB amplifier with 75Ω drivers for S-VHS
VCRs, HI-BAND VCRs, etc..Each channel has clamp function that
fixes DC level of video signal and 75Ω drivers to be connected to TV
monitors directly. Further more it has sag corrective circuits that
prevent the generation of sag with smaller capacitance than ever.
Its operating supply voltage is 4.85 to 9V and bandwidth is 7MHz.
■ FEATURES
● Wide Operating Voltage (4.85V to 9.0V)
● Dual Channel
● Internal Clamp Function
● Internal Driver Circuit For 75Ω Load
● SAG Corrective Function
● Wide Frequency Range (7MHz)
● Low Operating Current 14.0mA (Dual)
● Package Outline DIP8, DMP8, SSOP8
● Bipolar Technology
■ PACKAGE OUTLINE
NJM2267D
NJM2267M
NJM2267V
■ APPLICATIONS
●VCR, Video Camera, TV, Video Disc Player.
■ BLOCK DIAGRAM
Ver.2012-01-16
-1-
NJM2267
■ ABSOLUTE MAXIMUM RATINGS
PARAMETER
(Ta=25°C)
SYMBOL
+
RATINGS
UNIT
V
mW
mW
mW
Supply Voltage
Power Dissipation
V
PD
Operating Temperature Range
Topr
10
(DIP8) 500
(DMP8) 300
(SSOP8) 250
-40 to +85
Storage Temperature Range
Tstg
-40 to +125
°C
°C
(V+=5V, Ta=25±2°C)
■ ELECTRICAL CHARACTERISTICS
PARAMETER
SYMBOL
TEST CONDITION
MIN.
TYP.
MAX.
UNIT
-
14.0
18.2
mA
5.7
6.2
6.7
dB
Operating Current
ICC
No Signal
Voltage Gain
GV
VIN=1MHz, 1VP-PSinewave
Frequency Characteristics
Gf
VIN=1VP-P, Sinewave, 7MHz / 1MHz
-
-
±1.0
dB
Differential Gain
DG
VIN=1VP-P, Staircase
-
1.0
3.0
%
Differential Phase
DP
VIN=1VP-P, Staircase
-
1.0
3.0
deg
Crosstalk
CT
VIN=4.43MHz, 1VP-P, Sinewave
-
-70
-
dB
Gain Offset
GCH
VIN=1MHz, 1VP-P, GCH=VOUT1-VOUT2
-
-
±0.5
dB
Input Clamp Voltage
VCL
1.79
1.91
2.03
V
SAG Terminal Gain
GSAG
35
45
-
dB
■ APPLICATION
Oscillation Prevention
It is much effective to insert LPF (Cutoff Frequency 70MHz) under light loading conditions (RL » 1kΩ)
-2-
Ver.2012-01-16
NJM2267
(V+=5.0V, Ta=25°C)
■ TERMINAL FUNCTION
PIN No.
1
PIN NAME
Input
Clamp
Terminal
SYMBOL
VIN1
2
3
GND
SAG
correction
GND
VSAG1
Ground
SAG caused by a coupling capacitor of the output can be
prevented by connecting this terminal with the output terminal
through an external capacitor.(see block diagram)
When SAG correcting function is not necessary, this terminal
must be connected with pin “4” directly.
4
Video
Output1
VOUT1
Output terminal that can drive 75Ω line.
5
Video
Output2
VOUT2
Output terminal that can drive 75Ω line.
6
SAG
correction
VSAG2
SAG caused by a coupling capacitor of the output can be
prevented by connecting this terminal with the output terminal
through an external capacitor.(see block diagram)
When SAG correcting function is not necessary, this terminal
must be connected with pin “5” directly.
7
8
V+
Input
Clamp
Terminal
V+
VIN2
Supply Voltage
Input terminal of 1VP-P composite signal or Y signal.
Clamp level is 1.9V
Ver.2012-01-16
EQUIVALENT CIRCUIT
FUNCTIONS
Input terminal of 1VP-P composite signal or Y signal.
Clamp level is 1.9V
-3-
NJM2267
■ TEST CIRCUIT
■ TEST METHODES
PARAMETER
SYMBOL
SWITCH CONDITIONS
S1
S2
S3
S4
Supply Current
ICC
H
H
Voltage Gain
GV
H
H
ON
ON
Frequency
Characteristic
Gf
H
H
ON
ON
Differential Gain
DG
H
H
ON
ON
Differential Phase
DP
H
H
ON
ON
Crosstalk
CT
H
L
ON
ON
Gain Offset
GCH
H
H
ON
ON
Input Clamp Voltage
VCL
GSAG
H
H
H
H
H
H
SAG Terminal Gain
-4-
S5
S6
CONDITIONS
7PIN Sink Current
VOUT1 / VIN, VOUT2 / VIN2
at VIN1(VIN2)=1MHz, 1VP-P, Sinewave
GV1M; Voltage Gain at VIN1 (VIN2)=1MHz, 1VP-P
GV10M; Voltage Gain at VIN1 (VIN2)=7MHz, 1VP-P
Gf =GV10M-GV1M
Measuring VOUT3 at VIN1=Staircase Signal
ON
ON
Measuring VOUT3 at VIN1=Staircase Signal
VOUT2 / VOUT1 at VIN1=4.43MHz, 1VP-P, Sinewave
VOUT1 / VIN2 at VIN12=4.43MHz, 1VP-P, Sinewave
GV1=VOUT1 / VIN1, GV2=VOUT2 / VIN2
GCH=GV1-GV2
Measuring at TP1 (TP2)
TP3 (TP4) Voltage; Vo1A (Vo2A), TP5 (TP6) voltage;
Vso1A (Vso2A)
TP3 (TP4) Voltage; Vo1B(Vo2B), TP5 (TP6) voltage;
Vso1B (Vso2B)
GSAG=20log{ (Vo1B-Vo1A) / (Vso1A-Vso1B) }
GSAG=20log{ (Vo2B-Vo2A) / (Vso2A-Vso2B) }
Ver.2012-01-16
NJM2267
♦Clamp circuit
1. Operation of Sync-tip-clamp
Input circuit will be explained. Sync-tip clamp circuit (below the clamp circuit) operates to keep a sync tip of the minimum
potential of the video signal. Clamp circuit is a circuit of the capacitor charging and discharging of the external input Cin. It is
charged to the capacitor to the external input Cin at sync tip of the video signal. Therefore, the potential of the sync tip is fixed.
And it is discharged charge by capacitor Cin at period other than the video signal sync tip. This is due to a small discharge
current to the IC.
In this way, this clamp circuit is fixed sync tip of video signal to a constant potential from charging of Cin and discharging of
Cin at every one horizontal period of the video signal.
The minute current be discharged an electrical charge from the input capacitor at the period other than the sync tip of video
signals. Decrease of voltage on discharge is dependent on the size of the input capacitor Cin.
If you decrease the value of the input capacitor, will cause distortion, called the H sag. Therefore, the input capacitor
recommend on more than 0.1uF.
signal input
Cin
charge
current
Vin
Clamp circuit
diccharge
current
< Clamp circuit >
A. Cin is large
B. Cin is small (H sag experience)
clamp potential
clamp potential
charge period
discharge period
charge period
charge period
discharge period
charge period
< Waveform of input terminal >
2. Input impedance
The input impedance of the clamp circuit is different at the capacitor discharge period and the charge period.
The input impedance of the charging period is a few kΩ. On the other hand, the input impedance of the discharge period is
several MΩ. Because is a small discharge-current through to the IC.
Thus the input impedance will vary depending on the operating state of the clamp circuit.
3. Impedance of signal source
Source impedance to the input terminal, please lower than 200Ω. A high source impedance, the signal may be distorted. If
so, please to connect a buffer for impedance conversion.
Ver.2012-01-16
-5-
NJM2267
♦ SAG correction circuit
SAG correction circuit is a circuit to correct for low-frequency attenuation by high-pass filter consisting of the output coupling
capacitance and load resistance. Low-frequency attenuation raises the sag in the vertical period of the video signal.
Capacitor for Vsag (Csag) is connected to the negative feedback of the amplifier. This Csag increase the low frequency gain
to correct for the attenuation of low frequency gain.
Example SAG collection circuit
Vout
Cout
Vsag
Csag
resistance:RL
Vout1
Example of not using sag compensation circuit
Vout
Cout
resistance:RL
Vout1
Vsag
Waveform of Vout terminal and Vout1 terminal
using SAG correction circuit
Waveform of Vout
Waveform of Vout1
1Vertical period
-6-
not using SAG correction circuit
Waveform of Vout
Waveform of Vout1
1Vertical period
Ver.2012-01-16
NJM2267
SAG correction circuit generates a low frequency component signal amplified to Vout terminal.
Changes of the luminance signal will be low-frequency components, if you want to output a large signal luminance changes.
Therefore, generate correction signal of change of a luminance signal to Vout pin.
At this time, signal is over the dynamic range of Vout pin. This may cause a lack of sync signal, and waveform distortion.
Please see diagram below (green waveform), if you want to output large changes of a signal luminance, such as 100% white
video signal and black signal. Thus, output signal exceed dynamic range of Vout pin and may be the signal lack.
Input signal
Waveform of Vout
The sync signal is missing because exceed the dynamic
range of Vout.
Dynamic range of Vout
Waveform of Vout1
< Countermeasure for waveform distortion >
1. Please using small value the Sag compensation capacitor (VSAG).
It can ensure the dynamic range by using small value the capacitor (VSAG). It because of low-frequency variation of Vout pin
is smaller. However, the output (VOUT) must be use large capacitor for this reason sag characteristics become exacerbated.
2. Please do not use the sag correction circuit.
Signal can output within dynamic range for reason it does not change the DC level of the output terminal.
However, the output (VOUT) must be use large capacitor for this reason sag characteristics become exacerbated.
Ver.2012-01-16
-7-
NJM2267
Vcc=9.0V
Cout=330uF
Cout=220uF
Cout=100uF
Cout=47uF
Cout=33uF
< Using SAG correction circuit >
Csag=10uF, Input signal: bounce signal (IRE0%, IRE100%, 30Hz), resistance=150Ω
Waveform: yellow: input signal, green: Vout signal, purple: Vout1signa, red: clip length of waveform
Vcc=5.0V
Vcc=7.0V
-8-
Ver.2012-01-16
NJM2267
Vcc=9.0V
Cout=330uF
Cout=220uF
Cout=100uF
Cout=47uF
Cout=33uF
< Using SAG correction circuit >
Csag=22uF, Input signal: bounce signal (IRE0%, IRE100%, 30Hz), resistance=150Ω
Waveform: yellow: input signal, green: Vout signal, purple: Vout1signa, red: clip length of waveform
Vcc=5.0V
Vcc=7.0V
Ver.2012-01-16
-9-
NJM2267
Vcc=9.0V
Cout=330uF
Cout=220uF
Cout=100uF
Cout=47uF
Cout=33uF
< Using SAG correction circuit >
Csag=33uF, Input signal: bounce signal (IRE0%, IRE100%, 30Hz), resistance=150Ω
Waveform: yellow: input signal, green: Vout signal, purple: Vout1signa, red: clip length of waveform
Vcc=5.0V
Vcc=7.0V
- 10 -
Ver.2012-01-16
NJM2267
Vcc=9.0V
Cout=330uF
Cout=220uF
Cout=100uF
Cout=47uF
Cout=33uF
< Using SAG correction circuit >
Csag=10uF, Input signal: Black to White100%, resistance150Ω
Waveform: yellow: input signal, green: Vout signal, purple: Vout1signal, red: clip length of waveform
Vcc=5.0V
Vcc=7.0V
Ver.2012-01-16
- 11 -
NJM2267
Vcc=9.0V
Cout=330uF
Cout=220uF
Cout=100uF
Cout=47uF
Cout=33uF
< Using SAG correction circuit >
Csag=10uF, Input signal: White100% to Black, resistance150Ω
Waveform: yellow: input signal, green: Vout signal, purple: Vout1signal, red: clip length of waveform
Vcc=5.0V
Vcc=7.0V
- 12 -
Ver.2012-01-16
NJM2267
Vcc=9.0V
Cout=330uF
Cout=220uF
Cout=100uF
Cout=47uF
Cout=33uF
< Using SAG correction circuit >
Csag=22uF, Input signal: Black to White100%, resistance150Ω
Waveform: yellow: input signal, green: Vout signal, purple: Vout1signal, red: clip length of waveform
Vcc=5.0V
Vcc=7.0V
Ver.2012-01-16
- 13 -
NJM2267
Vcc=9.0V
Cout=330uF
Cout=220uF
Cout=100uF
Cout=47uF
Cout=33uF
< Using SAG correction circuit >
Csag=22uF, Input signal: White100% to Black, resistance150Ω
Waveform: yellow: input signal, green: Vout signal, purple: Vout1signal, red: clip length of waveform
Vcc=5.0V
Vcc=7.0V
- 14 -
Ver.2012-01-16
NJM2267
Vcc=9.0V
Cout=330uF
Cout=220uF
Cout=100uF
Cout=47uF
Cout=33uF
< Using SAG correction circuit >
Csag=33uF, Input signal: Black to White100%, resistance150Ω
Waveform: yellow: input signal, green: Vout signal, purple: Vout1signal, red: clip length of waveform
Vcc=5.0V
Vcc=7.0V
Ver.2012-01-16
- 15 -
NJM2267
Vcc=9.0V
Cout=330uF
Cout=220uF
Cout=100uF
Cout=47uF
Cout=33uF
< Using SAG correction circuit >
Csag=33uF, Input signal: White100% to Black, resistance150Ω
Waveform: yellow: input signal, green: Vout signal, purple: Vout1signal, red: clip length of waveform
Vcc=5.0V
Vcc=7.0V
- 16 -
Ver.2012-01-16
NJM2267
Cout=1000uF
Cout=470uF
Cout=330uF
Cout=220uF
Cout=100uF
< Not using SAG correction circuit >
Vcc=5V, Input signal: bounce signal (IRE0%, IRE100%, 30Hz), resistance=150Ω
Waveform: yellow: input signal, green: Vout signal, purple: Vout1signal
RL=150Ω
Ver.2012-01-16
- 17 -
NJM2267
■ TYPICAL CHARACTERISTICS
Operating Current vs. Ta
Output DC Level vs. Ta
SAG Terminal Gain vs. Ta
- 18 -
Input DC Level vs. Ta
SAG Terminal Voltage vs. Ta
Voltage Gain vs. Ta (Clamp Type INput)
Ver.2012-01-16
NJM2267
■ TYPICAL CHARACTERISTICS
Gain Frequency Characteristics
vs Ta (Clamp Type Input)
Ver.2012-01-16
Differential Gain vs. Ta
Differential Phase vs. Ta
Operating Current vs. Operating Voltage
Input DC Level vs. Operating Voltage
Output DC Level Vs. Operating Voltage
- 19 -
NJM2267
■ TYPICAL CHARACTERISTICS
SAG Terminal Voltage vs. Operating Voltage
Voltage Gain vs. Operating Voltage
Differential Gain vs. Operating Voltage
- 20 -
SAG Terminal Gain vs. Operating Voltage
Gain Frequency Characteristics
vs. Operating Voltage
Differential Phase vs. Operating Voltage
Ver.2012-01-16
NJM2267
■ TYPICAL CHARACTERISTICS
Voltage Gain vs. Frequency
Cross Talk vs. Frequency
Gain Frequency Characteristics vs. RL
Ver.2012-01-16
Small Signal Voltage Gain vs. Frequency
Voltage Gain vs. RL
Differential Gain vs. RL
- 21 -
NJM2267
■ TYPICAL CHARACTERISTICS
Differential Phase vs. RL
Differential Gain vs. APL
Differential Phase vs. APL
- 22 -
Ver.2012-01-16
NJM2267
■ APPLICATION
This IC requires 1MΩ resistance between INPUT and GND pin for clamp type input since the minute current
causes an unstable pin voltage.
[CAUTION]
The specifications on this databook are only
given for information , without any guarantee
as regards either mistakes or omissions. The
application circuits in this databook are
described only to show representative usages
of the product and not intended for the
guarantee or permission of any right including
the industrial rights.
Ver.2012-01-16
- 23 -