Datasheet

ManualsBrandsANALOG DEVICES ManualsLinear ICsLinear IC - Amplifier - Video buffering 80 MHz SOIC 8

CONNECTION DIAGRAM

8-Pin Plastic Mini-DIP (N), SOIC (R)

and Cerdip (Q) Packages

OFFSET

NULL

TOP VIEW

AD810

DISABLE

OUTPUT

OFFSET

NULL

–IN

+IN

–V

REV. A

Information furnished by Analog Devices is believed to be accurate and

reliable. However, no responsibility is assumed by Analog Devices for its

use, nor for any infringements of patents or other rights of third parties

which may result from its use. No license is granted by implication or

otherwise under any patent or patent rights of Analog Devices.

Low Power

Video Op Amp with Disable

AD810

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.

Tel: 617/329-4700 Fax: 617/326-8703

FEATURES

High Speed

80 MHz Bandwidth (3 dB, G = +1)

75 MHz Bandwidth (3 dB, G = +2)

1000 V/ms Slew Rate

50 ns Settling Time to 0.1% (V

= 10 V Step)

Ideal for Video Applications

30 MHz Bandwidth (0.1 dB, G = +2)

0.02% Differential Gain

0.048 Differential Phase

Low Noise

2.9 nV/√

Hz Input Voltage Noise

13 pA/√

Hz Inverting Input Current Noise

Low Power

8.0 mA Supply Current max

2.1 mA Supply Current (Power-Down Mode)

High Performance Disable Function

Turn-Off Time 100 ns

Break Before Make Guaranteed

Input to Output Isolation of 64 dB (OFF State)

Flexible Operation

Specified for 65 V and 615 V Operation

62.9 V Output Swing Into a 150 V Load (V

= 65 V)

APPLICATIONS

Professional Video Cameras

Multimedia Systems

NTSC, PAL & SECAM Compatible Systems

Video Line Driver

ADC/DAC Buffer

DC Restoration Circuits

PRODUCT DESCRIPTION

The AD810 is a composite and HDTV compatible, current

feedback, video operational amplifier, ideal for use in systems

such as multimedia, digital tape recorders and video cameras.

The 0.1 dB flatness specification at bandwidth of 30 MHz

(G = +2) and the differential gain and phase of 0.02% and

0.04° (NTSC) make the AD810 ideal for any broadcast quality

video system. All these specifications are under load conditions

of 150 Ω (one 75 Ω back terminated cable).

The AD810 is ideal for power sensitive applications such as

video cameras, offering a low power supply current of 8.0 mA

max. The disable feature reduces the power supply current to

only 2.1 mA, while the amplifier is not in use, to conserve

power. Furthermore the AD810 is specified over a power supply

range of ±5 V to ±15 V.

The AD810 works well as an ADC or DAC buffer in video

systems due to its unity gain bandwidth of 80 MHz. Because the

AD810 is a transimpedance amplifier, this bandwidth can be

maintained over a wide range of gains while featuring a low

noise of 2.9 nV/√

Hz for wide dynamic range applications.

0.10

0.03

0.01

0.02

0.06

0.04

0.05

0.07

0.08

0.09

1413121110987

0.20

0.18

0.16

0.14

0.12

0.10

0.08

0.06

0.04

0.02

GAIN

PHASE

GAIN = +2

= 715Ω

= 150Ω

= 3.58MHz

100 IRE

MODULATED RAMP

SUPPLY VOLTAGE – ± Volts

DIFFERENTIAL GAIN – %

DIFFERENTIAL PHASE – Degrees

Differential Gain and Phase vs. Supply Voltage

GAIN = +2

= 150Ω

±2.5V

±5V

±2.5V

PHASE

GAIN

–5

10 100

–1

–2

–3

–4

1 1000

–45

–90

–135

–180

–225

–270

CLOSED-LOOP GAIN – dB

PHASE SHIFT – Degrees

FREQUENCY – MHz

±5V

= ±15V

Closed-Loop Gain and Phase vs. Frequency, G = +2,

= 150, R

= 715

Ω

Summary of content (16 pages)

PAGE 1
a Low Power Video Op Amp with Disable AD810 FEATURES High Speed 80 MHz Bandwidth (3 dB, G = +1) 75 MHz Bandwidth (3 dB, G = +2) 1000 V/ms Slew Rate 50 ns Settling Time to 0.1% (VO = 10 V Step) Ideal for Video Applications 30 MHz Bandwidth (0.1 dB, G = +2) 0.02% Differential Gain 0.048 Differential Phase Low Noise 2.9 nV/√Hz Input Voltage Noise 13 pA/√Hz Inverting Input Current Noise Low Power 8.0 mA Supply Current max 2.
PAGE 2
AD810–SPECIFICATIONS (@ T = +258C and V = 615 V dc, R = 150 V unless otherwise noted) A Parameter DYNAMIC PERFORMANCE 3 dB Bandwidth 0.1 dB Bandwidth Full Power Bandwidth S L Conditions VS Min (G = +2) RFB = 715 (G = +2) RFB = 715 (G = +1) RFB = 1000 (G = +10) RFB = 270 (G = +2) RFB = 715 (G = +2) RFB = 715 VO = 20 V p-p, RL = 400 Ω RL = 150 Ω RL = 400 Ω 10 V Step, G = –1 10 V Step, G = –1 f = 3.58 MHz f - 3.58 MHz f = 3.58 MHz f = 3.
PAGE 3
AD810 Parameter Conditions 5 VS Turn On Time Turn Off Time Disable Pin Current ZOUT = Low, See Figure 54 ZOUT = High Disable Pin = 0 V Min Disable Pin Current to Disable TMIN–TMAX POWER SUPPLY Operating Range +25°C to TMAX TMIN ±5 V ± 15 V 170 100 50 290 ± 5 V, ± 15 V 30 ± 2.5 ± 3.0 ±5 V ± 15 V ± 5 V, ± 15 V ±5 V ± 15 V Quiescent Current TMIN–TMAX Power-Down Current AD810A Typ Max Min 6.7 6.8 8.3 1.8 2.1 Min AD810S1 Typ Max 170 100 50 290 75 400 75 400 ± 2.5 ± 3.5 6.7 6.8 9 1.8 2.
PAGE 4
20 MAGNITUDE OF THE OUTPUT VOLTAGE – ±Volts MAGNITUDE OF THE OUTPUT VOLTAGE – ±Volts AD810 –Typical Characteristics 20 15 NO LOAD 10 RL = 150Ω 5 15 NO LOAD 10 RL = 150Ω 5 0 0 0 5 10 15 SUPPLY VOLTAGE – ±Volts 0 20 Figure 1. Input Common-Mode Voltage Range vs. Supply Voltage 20 10 30 9 ±15V SUPPLY SUPPLY CURRENT – mA OUTPUT VOLTAGE – Volts p-p 10 15 SUPPLY VOLTAGE – ±Volts Figure 2. Output Voltage Swing vs.
PAGE 5
Typical Characteristics– AD810 120 100 200 VS = ± 15V OUTPUT CURRENT – mA SHORT CIRCUIT CURRENT – mA 250 VS = ±15V 150 100 80 60 VS = ± 5V 40 VS = ±5V 50 –60 –40 –20 0 +20 +40 +60 +80 +100 +120 20 –60 +140 –40 –20 +20 +40 +60 +80 +100 +120 +140 Figure 8. Linear Output Current vs. Temperature Figure 7. Short Circuit Current vs. Temperature 1M 10.
PAGE 6
AD810 –Typical Characteristics 90 70 POWER SUPPLY REJECTION – dB 80 COMMON-MODE REJECTION – dB 100 80 70 60 50 40 RF = 715Ω AV = +2 60 VS = ±15V 50 VS = ±5V 40 30 CURVES ARE FOR WORST CASE CONDITION WHERE ONE SUPPLY IS VARIED WHILE THE OTHER IS HELD CONSTANT 20 10 30 20 10k 100k 1M FREQUENCY – Hz 10M 100M 10k Figure 13. Common-Mode Rejection vs. Frequency 100k 1M FREQUENCY – Hz 10M 100M Figure 14. Power Supply Rejection vs.
PAGE 7
Typical Characteristics, Noninverting Connection–AD810 1V RF 20nS 100 +VS RG VIN 90 0.1µF VO TO TEKTRONIX P6201 FET PROBE 7 2 3 VO RL 0.1µF 10 50Ω 0% –VS 1V Figure 19. Noninverting Amplifier Connection Figure 20. Small Signal Pulse Response, Gain = +1, RF = 1 kΩ, RL = 150 Ω, VS = ± 15 V 0 –45 CLOSED-LOOP GAIN – dB –90 1 –135 VS = ±15V 0 –180 ±5V –1 –225 GAIN ±2.5V –270 –2 –3 VS = ±15V –4 ±5V ±2.
PAGE 8
AD810–Typical Characteristics, Noninverting Connection 100mV 100 90 100 VIN 90 VO VO 10 10 0% 0% 10V 1V Figure 26. Large Signal Pulse Response, Gain = +10, RF = 442 Ω, RL = 400 Ω, VS = ± 15 V Figure 25. Small Signal Pulse Response, Gain = +10, RF = 442 Ω, RL = 150 Ω, VS = ± 15 V GAIN = +10 RF = 270Ω 0 21 –135 20 –180 VS = ±15V 19 18 –225 ±5V GAIN VS = ±15V 17 ±5V 16 ±2.5V PHASE –270 ±2.5V 10 100 FREQUENCY – MHz ±5V 16 ±2.
PAGE 9
Typical Characteristics, Inverting Connection– AD810 1V 20nS RF 100 +VS RG VIN 90 0.1µF VO TO TEKTRONIX P6201 FET PROBE 7 2 VIN HP8130 PULSE GENERATOR 3 4 VO VO 6 AD810 RL 0.1µF 10 0% 1V –VS Figure 31. Inverting Amplifier Connection Figure 32. Small Signal Pulse Response, Gain = –1, RF = 681 Ω, RL = 150 Ω, VS = ± 5 V 45 CLOSED-LOOP GAIN – dB 0 –1 GAIN –2 0 –45 –90 VS = ±15V ±5V –4 ±2.5V 10 100 FREQUENCY – MHz –3dB BANDWIDTH – MHz 90 GAIN VS = ±15V –3 ±5V –4 ±2.
PAGE 10
AD810 –Typical Characteristics, Inverting Connection 100mV 1V 20nS 100 100 VIN 50nS VIN 90 90 VO VO 10 10 0% 0% 10V 1V Figure 38. Large Signal Pulse Response, Gain = –10, RF = 442 Ω, RL = 400 Ω, VS = ± 15 V Figure 37. Small Signal Pulse Response, Gain = –10, RF = 442 Ω, RL = 150 Ω, VS = ± 15 V 90 RL = 150Ω CLOSED-LOOP GAIN – dB 135 21 45 20 0 VS = ±15V 19 ±5V GAIN 18 17 ±5V ±2.5V 16 1 10 100 FREQUENCY – MHz 80 0 ±5V GAIN ±2.5V 18 ±5V 16 ±2.
PAGE 11
Applications– AD810 GENERAL DESIGN CONSIDERATIONS PRINTED CIRCUIT BOARD LAYOUT The AD810 is a current feedback amplifier optimized for use in high performance video and data acquisition systems. Since it uses a current feedback architecture, its closed-loop bandwidth depends on the value of the feedback resistor. Table I below contains recommended resistor values for some useful closedloop gains and supply voltages.
PAGE 12
AD810 CAPACITIVE LOADS LOAD CAPACITANCE – pF When used with the appropriate feedback resistor, the AD810 can drive capacitive loads exceeding 1000 pF directly without oscillation. By using the curves in Figure 45 to chose the resistor value, less than 1 dB of peaking can easily be achieved without sacrificing much bandwidth. Note that the curves were generated for the case of a 10 kΩ load resistor, for smaller load resistances, the peaking will be less than indicated by Figure 45.
PAGE 13
AD810 DIFFERENTIAL GAIN – % 0.09 When operated on ± 15 V supplies, the AD810 disable pin may be driven by open drain logic such as the 74C906. In this case, adding a 10 kΩ pull-up resistor from the disable pin to the plus supply will decrease the enable time to about 150 ns. If there is a nonzero voltage present on the amplifier's output at the time it is switched to the disabled state, some additional decay time will be required for the output voltage to relax to zero.
PAGE 14
AD810 2:1 VIDEO MULTIPLEXER 500mV 750Ω 750Ω The outputs of two AD810s can be wired together to form a 2:1 mux without degrading the flatness of the gain response. Figure 54 shows a recommended configuration which results in –0.1 dB bandwidth of 20 MHz and OFF channel isolation of 77 dB at 10 MHz on ± 5 V supplies. The time to switch between channels is about 0.75 µs when the disable pins are driven by open drain output logic.
PAGE 15
AD810 N:1 MULTIPLEXER 1kΩ A multiplexer of arbitrary size can be formed by combining the desired number of AD810s together with the appropriate selection logic. The schematic in Figure 58 shows a recommendation for a 4:1 mux which may be useful for driving a high impedance such as the input to a video A/D converter (such as the AD773).
PAGE 16
AD810 OUTLINE DIMENSIONS Dimensions shown in inches and (mm). Plastic Mini-DIP (N) Package 8 0.25 (6.35) PIN 1 1 C1737–24–10/92 5 0.31 (7.87) 4 0.30 (7.62) REF 0.39 (9.91) MAX 0.035 ±0.01 (0.89 ±0.25) 0.165 ±0.01 (4.19 ±0.25) 0.011 ±0.003 (0.28 ±0.08) 0.18 ±0.03 (4.57 ±0.76) 0.125 (3.18) MIN 0.018 ±0.003 (0.46 ±0.08) 0.10 (2.54) BSC 0.033 (0.84) NOM 15° 0° SEATING PLANE Cerdip (Q) Package 0.055 (1.40) MAX 0.005 (0.13) MIN 8 5 0.310 (7.87) 0.220 (5.59) PIN 1 1 4 0.320 (8.13) 0.290 (7.