SGM MHz Rail-to-Rail Composite Video Driver with 6dB Gain FEATURES PRODUCT DESCRIPTION APPLICATIONS BLOCK DIAGRAM. PIN CONFIGURATION (Top View)

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1 SGM9 PRODUCT DESCRIPTION The SGM9 is single rail-to-rail -pole output recotruction filter with a -db bandwidth of 8MHz and a slew rate of /µs. Operating from single supplies ranging from +. to +. and sinking an ultra-low.6ma quiescent current, the SGM9 is ideally suited for low power, battery-operated applicatio. The output swings within m of GND and 7m to + with a standard back-terminated video load (Ω). SGM9 employs an internal level shift circuit that avoids sync-pulse clipping and allows DC-coupled output. If AC-coupling is preferred, the SGM9 offers a sag-correction feature that significantly reduces the size of the output coupling capacitor. SGM9 has a power-down disable feature that reduces the supply current to µa, dramatically reducing power coumption and prolonging battery life. It is specified over the extended C to + C temperature range. BLOCK DIAGRAM -Pole Filter =. to. SGM9 Level Shifter GND DISABLE 6dB OUT SAG FEATURES Low Cost Excellent ideo Performance -Pole Recotruction Filter Internal Gain: 6dB Rail-to-Rail Output SAG Correction Reduces AC Coupling Capacitor size Input oltage Range Includes Ground AC-Coupled Input Operates on. to. Single-Supplies Low Power.6mA Typical Supply Current SGM9 µa when Disabled Small Packaging SGM9 Available in SC7-6 APPLICATIONS ideo amplifiers Cable and Satellite set top boxes Communicatio devices ideo on demand Portable and handheld products Personal video recorders DD players HDT P CONFIGURATION (Top iew) + GND SAG SGM9 9 6 SC7-6 DISABLE OUT RE. A

2 SGM9 PACKAGE/ORDERG FORMATION ORDER NUMBER PACKAGE DESCRIPTION TEMPERATURE RANGE PACKAGE OPTION MARKG FORMATION SGM9XC6/TR SC7-6 - to + Tape and Reel, 9 ABSOLUTE IMUM RATGS Supply oltage, + to Input oltage... GND -. to () +. Storage Temperature Range... 6 to + Junction Temperature...6 Operating Temperature Range... to + Power Dissipation, P T A = SC7-6...W Package Thermal Resistance SC7-6, θ JA... /W Lead Temperature Range (Soldering sec)...6 ESD Susceptibility HBM... MM... CAUTION This integrated circuit can be damaged by ESD. SGMICRO recommends that all integrated circuits be handled with appropriate precautio. Failure to observe proper handling and itallation procedures can cause damage. ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more susceptible to damage because very small parametric changes could cause the device not to meet its published specificatio. NOTES. Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only; functional operation of the device at these or any other conditio above those indicated in the operational section of this specification is not implied. Exposure to absolute maximum rating conditio for extended periods may affect device reliability.

3 SGM9 ELECTRICAL CHARACTERISTICS: S = +. (At R L = Ω connected to GND, and C =.µf, unless otherwise noted) SGM9 PARAMETER CONDITIONS + + / OER TEMPERATURE - - UNITS to7 to 8 to / PUT CHARACTERISTICS Output Level Shift oltage ( OLS ) =, no load 6 7 m Input oltage Clamp ( CLAMP) I = -ma m Clamp Charge Current = CLAMP -m ma Clamp Discharge Current = m µa oltage Gain ( A ) R L = Ω /....7 / OUTPUT CHARACTERISTICS Output oltage High Swing =, R L = Ω to GND..... Output Short-Circuit Current (I SC ) =, to GND through Ω 9 9 ma = m, out short to DD through Ω ma POWER SUPPLY Operating oltage Range Power Supply Rejection Ratio (PSRR) s = +.7 to db Quiescent Current (I Q) = m, Disable = s, no load ma Supply Current when Disabled Disable =. 6 µa DYNAMIC PERFORMANCE ±.db Bandwidth R L = Ω, C L = pf. MHz -db Bandwidth R L = Ω, C L = pf 8. MHz Filter Respoe Normalized Gain: f =.MHz +. db f = 7MHz - db Slew Rate % to 9%, = Step, /µs Differential Gain Error (DG) NTSC & PAL DC coupled.6 % NTSC & PAL AC coupled. % Differential Phase Error (DP) NTSC & PAL DC coupled.8 NTSC & PAL AC coupled. Group Delay ariation (D/DT) f = KHz, MHz 8 Fall Time. STEP, 8% to % Rise Time. STEP, 8% to % POWER-DOWN DISABLE Disabled (logic-low Threshold) s = +.7 to +..8 Disable (logic-high Threshold) s = +.7 to +..6 Disable Time = m, OUT to % 6 Disable Time = m, OUT to % 9 Disable Current Disable pin = na Specificatio subject to change without notice.

4 SGM9 ICAL PERFORMANCE CHARACTERISTICS At S = +., T A = +, R L = Ω, C L = pf unless otherwise noted. Frequency Respoe 7 Phase vs. Frequency Normalized Gain (db) Phase (degree) PSRR (db) PSRR vs. Frequency.. Group Delay () Group Delay vs. Frequency.. Gain (db) Gain vs. Frequency -db SAG Close -db 8MHz SAG Open -db Output oltage(m/div) Output oltage (m/div) Large-Signal Disable / Enable Respoe Enable Signal Output Signal Disable Signal Time (µs/div) 6 7 Time(µs/div)

5 SGM9 ICAL PERFORMANCE CHARACTERISTICS At S = +., T A = +, R L = Ω, C L = pf unless otherwise noted.. Large Signal Step Respoe. Small Signal Step Respoe Output oltage () Time () Output oltage ()... 6 Time () Quiescent Current (ma)..... Quiescent Current vs. Supply oltage No Load = m.... Supply oltage () Gain Error (%) Gain Error vs. Temperature Temperature ( ) Quiescent Current vs. Temperature Shutdown Current vs. Temperature Quiescent Current (ma).... Shutdown Current (µa) Temperature ( ) Temperature ( )

6 SGM9 ICAL PERFORMANCE CHARACTERISTICS At S = +., T A = +, R L = Ω, C L = pf unless otherwise noted. Output oltage (v) Output oltage Swing to The Positive Rail vs. Output Current Output Current (A) Output oltage (v) Output oltage Swing to The Negative Rail vs. Output Current = Output Current(A) 6

7 SGM9 Application Information The SGM9 low cost, integrated, -pole, video filter is intended to replace passive LC filters and drivers in low voltage portable video applicatio. The -pole filter provides better image quality compared to typical -pole solutio. The SGM9 input must be AC-coupled because the input capacitor stores the clamp voltage. It needs a typical value of.µf for the input clamp to meet the Line Droop specification. The SGM9 output can drive an AC or DC-coupled doubly terminated coax (Ω) load(see Figure ). DC-coupling the output removes the need for an expeive and large output coupling capacitor(see Figure ). If an AC-coupled output is needed, the SAG correction circuit can be used to reduce the AC output coupling capacitor value. Offering SAG correction, fixed gain of 6dB, and a -pole low pass filter in a tiny space saving package makes the SGM9 well suited for space seitive applicatio such as digital cameras,cellular phones and other portable devices. Enable/Shutdown The SGM9 has a shutdown feature that disables the output and reduces the quiescent current to µa. This feature is particularly useful in portable applicatio, such as video cameras, hand held gaming devices, cellular phones and requiring video filtering and drive capability. Internal Sync Clamp The typical embedded video DAC operates from a ground referenced single supply. This becomes an issue because the lower level of the sync pulse output may be at a reference level to some positive level. The problem is presenting a input to most single supply driven amplifiers will saturate the output stage of the amplifier resulting in a clipped sync tip and degrading the video image. A larger positive reference may offset the input above its positive range. The SGM9 features an internal sync clamp and offset function to level shift the entire video signal to the best level before it reaches the input of the amplifier stage. These features are also helpful to avoid saturation of the output stage of the amplifier by setting the signal closer to the best voltage range. The typical Application diagram of the SGM9 in Figure is divided into four sectio. The first, Section A is the Sync Clamp. The AC coupled video sync signal is pulled negative by a current source at the input of the comparator amplifier. When the sync tip goes below the comparator threshold the output comparator is driven negative, The PMOS device tur on clamping sync tip to near ground level. The network triggers on the sync tip of video signal. C R.µF C SYNC CLAMP R R C R DC C SALLEN KEY LOW PASS FILTER R R 6 OUT R SAG C = 7 µf C = µf AC COUPLG CAPACITOR R OUT 7 Ω R L 7 Ω DISABLE DISABLE = GND: SHUTDOWN I + ~ DISABLE = + S: ACTIE I + ~.6 ma R 7 GND SAG NETWORK Figure. Typical Application Diagram 7

8 SGM9 C R.µF C SYNC CLAMP R R C R DC C SALLEN KEY LOW PASS FILTER R R 6 OUT SAG R R OUT 7Ω R L 7Ω DISABLE DISABLE = GND: SHUTDOWN I+ ~ DISABLE = +S: ACTIE I+ ~.6mA R 7 GND SAG NETWORK Figure. AC-Coupled Input/DC-Coupled Output SAG Correction The SGM9 can use the SAG configuration if an AC-coupled output video signal is needed. SAG correction refers to the low-frequency compeation for the high pass filter formed by the Ω load and the output capacitor. In video applicatio, the cutoff frequency must be low enough to pass the vertical sync interval to avoid field tilt. This cutoff frequency should be less than Hz, and the coupling capacitor must be very large in normal configuration, typically is µf. In SAG configuration, the SGM9 removes the need for large coupling capacitors, and itead needs one µf and one 7µF capacitors (Figure ) to reach the same performance as the large capacitor. The Sallen Key Low Pass Filter The Sallen Key in a classic low pass configuration illustrated in Figure. The filter provides a very stable low pass function, and in the case of the SGM9, a -pole roll-off at around 8MHz. The -pole function is accomplished with an RC low pass network placed in series with and before the Sallen Key. One pole provided by the RC network and poles two and three provided by the Sallen Key for a nice -pole roll-off at around 8MHz. Layout and Power-Supply Bypassing The SGM9 operates from single. to. supply. Bypass the supply with a.µf capacitor as close to the pin as possible. SGMC recommends using microstrip and stripline techniques to obtain full bandwidth. To eure that the PC board does not degrade the device s performance, design it for a frequency greater than GHz. Pay careful attention to inputs and outputs to avoid large parasitic capacitance. Whether or not you use a cotant-impedance board, observe the following design guidelines: Do not use IC sockets; they increase parasitic capacitance and inductance. Do not use wire-wrap boards; they are too inductive. Use surface-mount itead of through-hole components for better, high-frequency performance. Use a PC board with at least two layers; it should be as free from voids as possible. Keep signal lines as short and as straight as possible. Do not make 9 tur; round all corners. 8

9 SGM9 PACKAGE OUTLE DIMENSIONS SC7-6 D e e E L θ E b A A Symbol Dimeio In Millimeters Dimeio In Inches Min Max Min Max A.9... A.... A b...6. C D E.... E A L C. e.6.6 e...7. L.REF.REF L θ 8 8 /6 RE. A SGMICRO is dedicated to provide high quality and high performance analog IC products to customers. All SGMICRO products meet the highest industry standards with strict and compreheive test and quality control systems to achieve world-class coistency and reliability. For information regarding SGMICRO Corporation and its products, see 9