Home

ANALOG DEVICES ADA4431-1 handbook

1. DC COUPLED 43 OUTPUT Connecting the center pin to the GND position short circuits the output causing the ADA4431 1 to power down and the LDO pin to go low If an external video load is connected to the OUT connector the jumper should be removed With the jumper removed disconnecting the external load also causes the ADA4431 1 to power down Jumper Block J4 exercises the disable pin DIS When a jumper is connected from the center pin to V the charge pump is enabled Connecting the center pin to GND forces the ADA4431 1 into low power mode With the jumper removed the ADA4431 1 is enabled but the charge pump is disabled A schematic of the ADA4431 1 evaluation board with output coupling options is shown in Figure 17 Figure 18 and Figure 19 show the front and back layout of the evaluation board AC COUPLED OUTPUT WITH SAG CORRECTION 06734 018 Figure 17 Evaluation Board Schematic Rev 0 Page 10 of 12 ADA4431 1 NC A 94V 0 3606 LO Wf Dies 8 ANALOG DEVICES EN ADAS431 1 EVAL BOARD Z ee GO Ong s v A014994 5 Figure 18 Evaluation Board Front Figure 19 Evaluation Board Back WN B ALI 06743 019 06743 020 Rev 0 Page 11 of 12 ADA4431 1 OUTLINE DIMENSIONS INDEX ie PIN 1 AREA pr INDICATOR 16 1 EXPOSED 1 80 i PAD 1 70 SQ 1 55 0 50 4 BSC TOP VIEW BOTTOM VIEW 0 40 MAX 30 NOM 2 60 0 05 MAX 0 55 Y T S 0 02 NOM i gt e SEATING 0 30 08
2. Each of these conditions occurs for a video load an audio load and no load respectively Only in the video load condition will the ADA4431 1 power up from 0 1 mA to 4 7 mA A single I O pin LDO notifies the system by either being high for a video load or low for a short and open load With this information it is intended that the system controller power down any power intensive video processing blocks to realize substantial power savings The ADA4431 1 operates autonomously requiring no inputs to monitor the condition of the output load Rev 0 Page 9 of 12 ADA4431 1 EVALUATION BOARD The ADA4431 1 evaluation board allows designers to assess the performance of the part in their particular application The board includes input and output SMA coaxial connectors and 75 Q controlled impedance signal traces Power 2 5 V to 3 6 V is applied to the red V loop connector and ground is connected to the black GND loop connector The output signal can be configured for dc coupling or ac coupling When ac coupled two options are available the standard single capacitor configuration minimum of 220 uF and the SAG corrected configuration using two smaller capacitors 47 uF and 22 uF Jumper Block J2 allows the load detect feature to be evaluated without connecting an external video load Connecting a jumper from the center pin to the 75 position applies a 75 Q load to the output and causes the LDO pin to go high OUTPUT OPTION 1
3. Pin 14 OUT Video Output 15 FB2 Load Detect Feedback Pin 2 Connect to device side of series termination resistor 16 FB1 Load Detect Feedback Pin 1 Connect to load side of series termination resistor Rev 0 Page 6 of 12 ADA4431 1 TYPICAL PERFORMANCE CHARACTERISTICS Vs 3 0 V Ta 25 C Vin 1 V p p Ri 150 Q unless otherwise noted CHARGE a T z 5 z E a ul ul A N a z 2 x o z fa oO z CHARGE PUMP ON 0 1 1 10 100 8 FREQUENCY MHz 5 FREQUENCY MHz 5 Figure 5 Large Signal Frequency Response Figure 8 Group Delay vs Frequency Vin 100mV p p 5 DIS 3V H e lA 10 Td E CHARGE PUMP ON m 15 z X ao 20 3 n m y CHARGE PUMP OFF a ay aj 25 2 a 230 z amp o 35 z 40 45 2 50 2 0 1 1 10 0 1 1 10 100 FREQUENCY MHz 8 FREQUENCY MHz S Figure 6 Frequency Response Flatness Figure 9 PSRR vs Frequency T T 2 z z lt q lt q oO a a ul ul N N d d q q 4 4 o o z z E 1 E FREQUENCY MHz 5 FREQUENCY MHz 5 Figure 7 Input to Output Isolation vs Frequency Figure 10
4. W 1 0 40 30 20 10 0 10 20 30 40 50 60 70 80 90 100 AMBIENT TEMPERATURE C 06743 003 Figure 3 Maximum Power Dissipation vs Temperature for a 4 Layer Board ESD CAUTION ESD electrostatic discharge sensitive device Charged devices and circuit boards can discharge y Y without detection Although this product features patented or proprietary protection circuitry damage dy A may occur on devices subjected to high energy ESD Therefore proper ESD precautions should be taken to avoid performance degradation or loss of functionality Rev 0 Page 5 of 12 ADA4431 1 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS E a a gt Ei uu O o Se Vs 1 D C 12 GND IN2 5 ADA4431 1 11 SUBS TOP VIEW DIS 3 DO Not to Scale C 10 Vs LDO 4 D C 9 CAP1 M a z o CAP4 5 D CAP3 6 CAP2 8 06743 004 Figure 4 Pin Configuration Table 5 Pin Function Descriptions Pin No Mnemonic Description 1 Vs Supply Voltage 2 IN Video Input 3 DIS Disable Pin High charge pump on floating charge pump off low disabled 4 LDO Load Detect Output High video load present 5 CAP4 Capacitor 2 Lead 2 6 CAP3 Capacitor 2 Lead 1 7 GND Ground 8 CAP2 i j Capacitor 1 Lead 2 A i 9 CAP1 T Capacitor Ledo 10 Vs Supply Voltage 11 SUBS Substrate Voltage Pin Bypass to GND with 1 0 uF capacitor 12 GND Ground 13 SAG SAG Feedback
5. low as 2 5 V The ADA4431 1 also features a load detect circuit which senses current through the external 75 Q back termination resistor When either no video load or a short circuit is detected the ADA4431 1 enters a low power state In this state it draws 0 1 mA continues to monitor the load current and powers up automatically when a video load is connected Optionally the ADA4431 1 can be powered down via the disable pin DIS Another external pin LDO outputs the load detection state for example to an external system controller This pin is high Vs when a video load is present and low 0 V in the absence of a video load or when the output is short circuited The ADA4431 1 is intended for use in applications that have both ac and dc coupled inputs and outputs The rail to rail buffer on the ADA4431 1 output is able to drive 2 V p p video signals into two doubly terminated video loads 150 each on a single 2 5 V supply The ADA4431 1 has a gaimof2 when the SAG correction pin is tied directly tofthe output Which makes up for the 6 dB termination loss see Figure47 Output ption P When the SAG feature is used the ADA4431 1 has a low frequency gain of 2 5 8 dB and a high frequency gain of 2 see Figure 17 Output Option 2 Signal offsets and supply levels must be considered when using the SAG correction feature to ensure that there are no headroom issues The input range of the ADA4431 1 includes ground while the
6. output range is limited by the saturation of the output devices Saturation occurs several tens of mV from the positive and negative supply rails The high input impedance and low input capacitance of the ADA4431 1 offer advantages in a number of low power applications In reconstruction filter applications the DAC can be placed in its lowest power mode allowing the use of a large valued load resistor Using a large valued load resistor does not interfere with the frequency response of the ADA4431 1 CHARGE PUMP OPERATION The on board charge pump creates a virtual negative supply for the output driver which allows the output signal to be dc coupled with its black level at 0 V and sync tip at 300 mV The charge pump is enabled whenever the disable pin DIS is held high If DIS is left floating or placed in a high impedance state the ADA4431 1 is powered up but the charge pump is disabled which is typically the case for ac coupling of the output When DIS is driven to 0 V the entire device is powered down Table 6 Disable DIS Pin Function Summary DIS Pin Device State Charge Pump State Low Disabled Disabled High Enabled Enabled High Z Enabled Disabled LOAD DETECT The ldad detetffeature pu additional system power management to Keep thelpewer consumption of a portable device to the absolute minimum The ADA4431 1 monitors the output load for three conditions a normal load a shorted load and an open load
7. the ADA4431 1 package is limited by the associated rise in junction temperature Tj on the die At approximately 150 C which is the glass transition temperature the plastic changes its properties Even temporarily exceeding this temperature limit can change the stresses that the package exerts on the die permanently shifting the parametric performance of the ADA4431 1 Exceeding a junction temperature of 150 C for an extended period can result in changes in the silicon devices potentially causing failure ADA4431 1 The power dissipated in the package Pp is the sum of the quiescent power dissipation and the power dissipated in the package due to the load drive The quiescent power is the voltage between the supply pins Vs times the quiescent current Is The power dissipated due to the load drive depends upon the particular application The power due to load drive is calculated by multiplying the load current by the associated voltage drop across the device RMS voltages and currents must be used in these calculations Airflow increases heat dissipation effectively reducing 074 In addition more metal directly in contact with the package leads and exposed pad from metal traces through holes ground and power planes reduces the Oya Figure 3 shows the maximum safe power dissipation in the package vs the ambient temperature for the 16 lead LFCSP package 43 C W on a JEDEC standard 4 layer board MAXIMUM POWER DISSIPATION
8. ANALOG DEVICES Ultralow Power SD Video Filter with Load Detection ADA4431 1 FEATURES Third order low pass video filter 1 dB flatness out to 6 MHz 27 dB rejection at 27 MHz Low quiescent current 4 7 mA typical Low power down current 24 pA typical Load detection capability SAG correction Allows use of smaller capacitors in ac coupled outputs Low supply voltage 2 5 V to 3 6 V Charge pump Creates a negative voltage from single positive supply Allows capless output coupling with no dc offset Rail to rail output High input to output isolation in disabled state 89 dB 1 MHz Small package 3mm x 3 mm LFCSP Low 0 55 mm package height Wide operating temperature range 40 C to 85 C h 1 APPLICATIONS UWV Portable media players Portable gaming consoles Cell phones Digital still cameras Portable DVD players Portable video cameras GENERAL DESCRIPTION The ADA4431 1 is a fully integrated video reconstruction filter that combines excellent video specifications with low power consumption making it ideal for portable video filtering applications The ADA4431 1 is able to detect whether a video load is present at the output powering down the device when the load is disconnected The ADA4431 1 operates on single supplies as low as 2 5 V while providing the dynamic range required by the most demanding video systems The on board charge pump provides a virtual negative supply allowing the video signal to be dc coupled and
9. BEE PLANE 025 0 18 053106 B COMPLIANT TO JEDEC STANDARDS MO 248 UEED Figure 20 16 Lead Lead Frame Chip Scale Package LFCSP_UQ 3mm x 3 mm Body Ultra Thin Quad CP 16 12 Dimensions shown in millimeters ORDERING GUIDE Model A M bcidion Peete E Ordering Quantity ADA4431 1YCPZ R2 40 C to 85 C T6 Lead LFCSP_UQ CP 16 12 250 ADAA431 1YCPZ R7 40 C to 85 C 16 Lead LFCSP_UQ CP 16 12 3 000 ADA4431 1YCPZ RL 40 C to 85 C 16 Lead LFCSP_UQ CP 16 12 10 000 1 Z RoHS Compliant Part 2007 Analog Devices Inc All rights reserved Trademarks and ANALOG registered trademarks are the property of their respective owners D06734 0 8 07 0 DEVICES www analo g com Rev 0 Page 12 of 12
10. Frequency Response for Various Temperatures Rev 0 Page 7 of 12 ADA4431 1 SUPPLY CURRENT mA SUPPLY CURRENT mA wo 0 85 C a 25 c S eC Zz 2 40 c lt a 3 N al 3 4a x o Z 5 6 7 0 1 1 10 FREQUENCY MHz Figure 11 Flatness Response for Various Temperatures 0 0 5 1 0 1 5 2 0 2 5 3 0 DISABLE DIS PIN VOLTAGE V Figure 12 Supply Current vs Disable DIS Pin Voltage 0 0 40 30 20 10 0 10 20 30 40 50 60 70 80 90 TEMPERATURE C Figure 13 Supply Current vs Temperature 06734 011 06734 012 DISABLED SUPPLY CURRENT yA 06734 014 Rev 0 Page 8 of 12 200mv M100ns A CH1 J 316mV Figure 14 Transient Response 2 00V CH2 500mV M10 0ms Figure 15 Output Enable A CH1 JS 1 72V CH2 500mV M40 0ns Figure 16 Output Disable A CH1 V 1 72V 06734 015 06734 016 06734 017 ADA4431 1 THEORY OF OPERATION OVERVIEW The ADA4431 1 is designed for exceptional performance as both a filter and a low power driver for portable video applications This performance is achieved by providing third order filtering without trading off power consumption or device size While consuming only 4 7 mA quiescent supply current the ADA4431 1 provides video output on a single supply as
11. f 27 MHz 26 29 dB Differential Gain Modulated 10 step ramp sync tip at OV 0 4 Differential Phase Modulated 10 step ramp sync tip at OV 0 3 Degrees Linear Output Current q 7 mA Group Delay Variation 9 xj ns fa TOOlkHz to 5 MHz T Rev 0 Page 4 of 12 ABSOLUTE MAXIMUM RATINGS Table 3 Parameter Rating Supply Voltage 4 0V Power Dissipation See Figure 3 Storage Temperature Range 65 C to 125 C Operating Temperature Range 40 C to 85 C Lead Temperature Soldering 10 sec 300 C Junction Temperature 150 C 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 conditions above those indicated in the operational section of this specification is not implied Exposure to absolute maximum rating conditions for extended periods may affect device reliability THERMAL RESISTANCE Oya is specified for the device including exposed pad soldered to a high thermal conductivity 2s2p circuit board as described in EIA JESD 51 7 The exposed pad is not electrically connected to the device It is typically soldered to a pad on the PCB that is thermally and electrically connected to an internal ground plane Table 4 Thermal Resistance i 4 Package Type Osa Unit 16 lead LFCSP UQ CP 16 12 43 C W MAXIMUM POWER DISSIPATION The maximum safe power dissipation in
12. ion and Function Descriptions 6 Applications issie t spse iiaei a aa E EE aaa E ARa 1 Typical Performance Characteristics sees 7 Pin Configurations ie ttl Eee e aet enet de ien tnt brtesd 1 Theory OL Operations eterne a tede etna 9 General Description scient ett tiene o a 1 OVErVIEW Gucci e RO ROO eae 9 ReVISIOtDEDIStOEY Lesen esie to sid ie E 2 Charge Pump Operation seen 9 Sp cifications 4er tte RD ere ere 3 Load Detectar E PEE 9 Absolute Maximum Ratings seen 5 Evaluation Board cnet eene 10 Thermal R sistatice eid nette itn eie ite edet 5 Outline Dimensions sse 12 Maximum Power Dissipation seen 5 Ordering Guide t REN FS 12 ESD Cautiona ceni RR REN RERUM 5 REVISION HISTORY 8 07 Revision 0 Initial Version IN D ALI Rev 0 Page 2 of 12 SPECIFICATIONS Vs 3 0 V Ta 25 C Vin 1 V p p Ri 150 Q DIS 3 0 V charge pump on unless otherwise noted ADA4431 1 Table 1 Parameter Test Conditions Comments Min Typ Max Unit ELECTRICAL SPECIFICATIONS Quiescent Supply Current Normal Mode Video load present 4 7 7 2 mA Load Searching Mode No video load 0 1 mA Disabled Mode DIS 0V 24 pA Disable Pin Current DIS 3 0 V enabled and charge pump on 3 6 pA DIS 0 V disabled 17 30 yA Supply Voltage Range 2 5 3 6 V Input Voltage Limited by output range 1 3 V Input Resistance 10 MO In
13. put Capacitance 1 pF Output Voltage Range 0 8 to 42 8 V Output Offset Voltage 650 600 560 mV Power Supply Rejection f 100 kHz output referred 36 42 dB Pass Band Gain 5 7 6 0 6 2 dB Input to Output Isolation Disabled f 1 MHz DIS 0V 89 dB FILTER CHARACTERISTICS 3 dB Bandwidth 7 1 7 9 9 1 MHz 1 dB Flatness 6 MHz Out of Band Rejection T227MHz 25 7 dB Differential Gain i Mogulated 10 step ramp sync tip at0V v 96 Differential Phase Modulated 10 step ramp sync tip at OV 0 3 Degrees Linear Output Current 40 mA Group Delay Variation f 100 kHz to 5 MHz 30 ns Rev 0 Page 3 of 12 ADA4431 1 Vs 3 0 V Ta 25 C Vin 1 V p p Ri 150 Q DIS floating charge pump off unless otherwise noted Table 2 Parameter Test Conditions Comments Min Typ Max Unit ELECTRICAL SPECIFICATIONS Quiescent Supply Current Normal Mode Video load present 1 6 2 2 mA Load Searching Mode No video load 0 1 mA Disabled Mode DIS 0V 24 yA Disable Pin Current DIS 0V 17 30 yA Supply Voltage Range 2 5 3 6 V Input Voltage Limited by output range 13 V Input Resistance 10 MO Input Capacitance 1 pF Output Voltage Range 0 to 2 8 V Output Offset Voltage 0 1 0 2 V Power Supply Rejection f 100 kHz output referred 38 48 dB Pass Band Gain 5 8 6 0 6 2 dB Input to Output Isolation Disabled f 1 MHz DIS 0V 89 dB FILTER CHARACTERISTICS 3 dB Bandwidth 6 7 7 5 8 4 MHz 1 dB Flatness 6 MHz Out of Band Rejection
14. the black level to be set to ground while the sync passes cleanly at 300 mV below ground Rev 0 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 that may result from its use Specifications subject to change without notice No license is granted by implication or otherwise under any patent or patent rights of Analog Devices Trademarks and registered trademarks are the property of their respective owners PIN CONFIGURATION C 12 GND C 11 SUBS C 10 Vs LDO 4 C 9 CAP4 CHARGE PUMP N e N ggg o o0 9 SG s Figure 1 Vs SYSTEM CONTROLLER 06734 002 0 1pF 0 1pF 1 0pF Figure 2 Typical Application Circuit When operating with the charge pump off the ADA4431 1 provides a dc offset to keep the sync tip approximately 100 mV above ground In addition the part features SAG correction which permits the use of smaller capacitors in applications with ac coupled outputs The ADA4431 1 is packaged in a low profile 16 lead LFCSP and operates in the industrial temperature range of 40 C to 85 C One Technology Way P O Box 9106 Norwood MA 02062 9106 U S A Tel 781 329 4700 www analog com Fax 781 461 3113 2007 Analog Devices Inc All rights reserved ADA4431 1 TABLE OF CONTENTS inl 1 Pin Configurat

ANALOG DEVICES ADA4431-1 handbook

Contents

Download Pdf Manuals

Related Search

Related Contents