temperature compensating gamma trimster? att3209 proprietary and confidential rev 2/7/2005 pr eliminary information features 9 programmable buffered gamma correction outputs (v gma 0 ? v gma 8) - v gma output range 0 to 14v - v gma output accuracy better than 1% of a vdd reference - v gma output drive > 100 m a nonvolatile storage of 32 gamma reference providing - dynamic gamma correct ion and gamma correction based on programmed temperature profiles 2 programmable buffered v com outputs in system programmability digital programming interface applications yield improvement through gamma programming at test simple implementation of dynami c gamma compensation lcd panel color calibration optimized temperature dependent gamma correction description the att3209 is a programmable gamma reference that is designed to address gamma correction in high - resolution lcd panels. the gamma voltage out puts are programmable with their individual output values saved in a nonvolatile analog storage cell. the storage cells are arranged in a 9 x 32 array allowing thirty - two gamma correc tion profiles to be stored. depending upon the application requirements the att3209 is configured to provide either two or three temperature compensated bank select outputs that would be used to drive the respective bank select inputs of the ag t3209 gamma trimster. in addition to the v gma outputs there are two programmable v c om outputs providing independent multiple v com trim points to minimize flicker on the lcd panel. typical application
alta analog att3209 proprietary and confidential page 2 revision 2/7/2005 absolute maximum ratings over operating free - air temperature range unless otherwise specified (1) parameter max unit analog supply, a v dd (2) 14.5 v delta v ref 1 and v ref 2, delta v ref 9 v programming supply v pp 14 v digital supply v cc 5 v continuous total power dissipation ma operating free - air temperature range, t a - 25 to +125 oc maximum junction temperature, t j 150 oc storage temp erature, t stg - 65 to 150 oc lead temperature 1.6mm (1/16 inch) from case for 10 seconds 260 oc (1) stresses beyond those listed under ?absolute maximum ratings? may cause permanent damage to the device. these are stress ratings only and functional operatio n of the device at these or any other conditions beyond those indicated under ?recommended operating conditions? is not implied. exposure to absolute maximum rated conditions for extended periods may affect device reliability. (2) all voltage values are with respect to v ss . dissipation rating table package type package designator theta jc theta ja 32 lead mlf (qfn) 1.1 o c/w 34 o c/w recommended operating conditions symbol parameter min typ max units t a operating free air temperature 0 85 o c a vdd analog supp ly voltage (with respect to v ss ) 10 13 14 v v pp programming supply voltage (with respect to v ss ) 9 10 14 v v cc digital supply voltage (with respect to v ss ) 2.7 3.3 3.6 v
alta analog att3209 proprietary and confidential page 3 revision 2/7/2005 electrical character istics operating over free - air temperature range, v pp = 9v t o 14v, v cc = 3.3v, a vdd = 14v supplies symbol parameter test condition min typ max units i avdd analog supply current v gma 0 thru v gma 8 = nominal setting v ref 1/v ref 2 delta 9v 9 ma i cc digital supply current active vcc = 3.3v, b0 - b5, sda, v pp = gnd 300 m a analog characteristics symbol parameter test condition min typ max units v com vcom1, vcom2 output voltage, low i o = 100 a v com - 1v vcom in v com +1v v v prog vgma p rogramming precision - 5 2.5 +5 mv v drift vgma drift 10 years @ 70 deg. c. - 5 5 mv v stab vgma stability over operating conditions - 5 5 mv v ref delta1 v ref 1 - v ref 2 9 v v ref delta2 v ref 2 - v ref 1 9 v dc operating characteristics symbol parameter test condition min typ max units v il sda, b0 - b5 input low voltage v cc x.20 v v ih sda, b0 - b5 input highvoltage v cc x0.8 v t dly delay b0 - b5 change to vgma output ms note: detailed programming information is available from alta analog in the att32 09 addendum.
alta analog att3209 proprietary and confidential page 4 revision 2/7/2005 nominal v gma is dependent upon v ref 1 and v ref 2 and is calculated as follows: r ratio x(v ref 2 - v ref 1)+v ref 1 first order ga mma curve values symbol parameter test condition min. trim nom max trim units v gma 0 gamma 0 output r ratio 0 = 0.909 v ref 2 = 14v, v ref 1 = 7v 12.363 13.363 14.363 v v gma 1 gamma 1 output r ratio 1 = 0.660 v ref 2 = 14v, v ref 1 = 7v 10.618 11.618 12.618 v v gma 2 gamma 2 output r ratio 2 = 0.525 v ref 2 = 14v, v ref 1 = 7v 9.672 10.672 11.672 v v gma 3 gamma 3 output r ratio 3 = 0.393 v ref 2 = 14v, v ref 1 = 7v 8.754 9.754 10.754 v v gma 4 gamma 4 output r ratio 4 = 0.319 v ref 2 = 14v, v ref 1 = 7v 8.231 9.231 10.231 v v gma 5 gamma 5 output r ratio 5 = 0.264 v ref 2 = 14v, v ref 1 = 7v 7.849 8.849 9.849 v v gma 6 gamma 6 output r ratio 6 = 0.180 v ref 2 = 14v, v ref 1 = 7v 7.262 8.262 9.262 v v gma 7 gamma 7 output r ratio 7 = 0.024 v ref 2 = 14v, v ref 1 = 7v 6.168 7.168 8.168 v v gma 8 gamma 8 output r ratio 8 = 0 v ref 2 = 14v, v ref 1 = 7v 6 7 8 v v gma 9 gamma 8 output r ratio 8 = 0 v ref 2 = 0v, v ref 1 = 7v 6 7 8 v v gma 10 gamma 7 output r ratio 7 = 0.024 v ref 2 = 0v, v ref 1 = 7v 5.832 6.832 7.832 v v gma 11 gamma 6 output r ratio 6 = 0.180 v ref 2 = 0v, v ref 1 = 7v 4.74 5.74 6.74 v v gma 12 gamma 5 output r ratio 5 = 0.264 v ref 2 = 0v, v ref 1 = 7v 4.152 5.152 6.152 v v gma 13 gamma 4 output r ratio 4 = 0.319 v ref 2 = 0v, v ref 1 = 7v 3.767 4.767 5.767 v v gma 14 gamma 3 output r ratio 3 = 0.393 v ref 2 = 0v, v ref 1 = 7v 3.249 4.249 5 .249 v v gma 15 gamma 2 output r ratio 2 = 0.525 v ref 2 = 0v, v ref 1 = 7v 2.325 3.325 4.325 v v gma 16 gamma 1 output r ratio 1 = 0.660 v ref 2 = 0v, v ref 1 = 7v 1.38 2.38 3.38 v v gma 17 gamma 0 output r ratio 0 = 0.909 v ref 2 = 0v, v ref 1 = 7v 0 0.637 1.637 v
alta analog att3209 proprietary and confidential page 5 revision 2/7/2005 input / output function description name description value range function v dd digital supply input 3v to 3.3v a vd d analog supply 10 - 14 v v gma 0 - v gma 8 analog outputs v ref 1 to v ref 2 analog gamma output channels b0 ? b2 bank select i/o?s during normal att3209 operation the b0 ? b2 pins are outputs that output the result of the temperature profile logic. b3 ? b5 bank select cmos inputs the b3 - b5 inputs are the dynamic bank select inputs. the state of dtsel determines whether the banks are arranged as 8 banks of 4 profiles or 4 banks of 8 profiles. v ref 1/ v ref 2 input reference voltages 0 - 14 volts reference voltages fo r generating vgma outputs. a out analog output outputs the current value of the selected channel of the selected bank during programming v pp programming voltage & serial clock 10 - 14volts v il to v ih dual function: programming mode - input for vpp pulses for adjusting the vgma output values. digital mode ? clock input for serial interface. dtsel temperature profile select cmos input internally this input tied to ground through a 100k ohm resistor. the state of dtsel selects the five b inputs that will be used by the att3209. dtsel low configures the array 4 banks of 8 temperature profiles. dtsel high configures the array 8 dynamic banks of 4 temperature profiles. vtemp temperature sensor input internally this input tied to ground through a 100k ohm res istor. temperature sensor input to the programmable temperature profile array. atten att enable input cmos input internally this input tied to ground through a 100k ohm resistor. this input should be tied directly to vcc for normal device operation. osc oscillator output osc is an output used during test and will be a no ? connect during normal device operation. ben bank enable
alta analog att3209 proprietary and confidential page 6 revision 2/7/2005 functional description the att3209 is a programmable gamma correction reference device with high drive output buffers. the device can be easil y programmed prior to or during any phase of the lcd - panel manufacturing process. the gamma reference voltages are programmed and saved on nonvolatile storage cells. vgma figure 1 shows a typical gamma correction curve with 18 reference points. the att 3209 v gma outputs can be programmed to match any point on the curve. the 9 outputs (v gma 0 through v gma 8 ) approximate one half of the curve. internal to the att3209, between v ref 1 and v ref 2, there is a resistor string along which are tap points that appr oximate a first order gamma curve. the nominal v gma reference voltages are a ratio of the voltage differential between the v ref inputs and are calculated by the following: r ratio * (v ref 2 - v ref 1) +v ref 1 . the r ratio values are shown in table 1. the nomina l v gma value can be trimmed 1v by programming, with the final value being stored on a nonvolatile storage cell. because the resistor string is fixed to approximate one half of the gamma curve the v ref inputs are reversible with respect to which is more po sitive. as an example: in order to generate the points on the gamma curve shown in figure 1the att3209 generating v gma 0 - v gma 8 would have its v ref 1 tied to v com and v ref 2 tied to a vdd . the att3209 generating v gma 9 - v gma 17 would have its v ref 1 tied to v com and v ref 2 tied to v ss . the v gma buffers can drive the outputs to within 200mv of a vdd and v ss . figure 1: typical gamma correction curve.
alta analog att3209 proprietary and confidential page 7 revision 2/7/2005 vgma r ratio v gma 0 0.909 v gma 1 0.660 v gma 2 0.525 v gma 3 0.393 v gma 4 0.319 v gma 5 0.264 v gma 6 0.180 v gma 7 0.024 v gma 8 0.000 table1: r ratio table. dynamic gamma compensation in many applications, especially those which involve the display of video information such as movies or television programming, it is desirable to be able to change the gamma curve based on the active frame information. the att3209 sto res thirty - two individual gamma curves that can be dynamically ?switched in? by the panel?s timing controller in response to the frame data. temperature and gamma profiles the att3209 has two nonvolatile arrays. one is the temperature profile. this array stores up to eight programmable voltage references against which the vtemp input is compared. as the vtemp changes and transitions through the preset temperature profile the low order bank select (b0:b1 or b0:b2) will change, effectively selecting a new gamma profile optimal for the current temperature. these signals used internally will also be output on the b0:b2 pins. the gamma profile array is comprised of thirty - two (32) banks of nine (9) programmable gamma outputs. the active bank, or profile, i s selected by 5 of the 6 bank select inputs. the active bank select inputs are determined by the state of dtsel as shown in table 2. att3209 active and inactive bank pins dtsel b0 b1 b2 b3 b4 b5 vss a a a a a ia vcc a a ia a a a table 2. active bank select pins. when dtsel is tied low, the att3209 is configured with b0:b2 being used internally and as active outputs reflecting the temperature input , and b3 & b4 are used as the dynamic gamma inputs. when dtsel is tied high, the att3209 is configured w ith b0 & b1 being used internally and as active outputs reflecting the temperature input, and b3:b5 are used as the dynamic gamma inputs. att3209 and AGT3209 the att3209 is designed to work in conjunction with the AGT3209. when they are paired the, the b ank select pins are connected as shown in table 3. AGT3209 pins b0 b1 b2 b3 b4 vss b0 b1 b2 b3 b4 att3209 dtsel vcc b0 b1 b3 b4 b5 table 3 . shared pins. vcom the att3209 also provides two ?trimmable? v com outputs. the nominal output is equiv alent to panel a vdd /2. the v com output voltage can be trimmed to a vdd /2 1v. for example; assume a lcd panel with a 14v panel a vdd , then v com can be trimmed anywhere between 6v and 8v effectively in 8mv increments. the att3209 is easily programmed either by alta analog or the end user. it can be programmed as a standalone device in most any test fixture or in - circuit on the assembled lcd - panel. programming the programming interface is a set of three inputs plus a digital supply (v cc ). sda is the seri al data input pin used to input instructions to the att3209. v pp is a dual function pin. it is first used to clock in the serial data stream. once the instruction has been issued v pp will then be used as the programming voltage input pin. a out is a buffe red analog voltage output that reflects the v gma voltage level of the cell
alta analog att3209 proprietary and confidential page 8 revision 2/7/2005 currently being programmed. this output is only used during the programming operation. operation once the att3209 is programmed it will power - up with the v gma and v com outputs at th eir selected (state of b0 - b4) program levels.
alta analog att3209 proprietary and confidential page 9 revision 2/7/2005 att3209 functional block diagram
alta analog att3209 proprietary and confidential page 10 revision 2/7/2005 this is a preliminary information data sheet that describes an alta analog product currently in development. it is meant solely as a product description and should not be used as a design tool. alta ana log, inc. reserves the right to make changes to the products contained in this publication in order to improve design, performance or reliability. alta analog, inc. assumes no responsibility for the use of any circuits described herein, conveys no license under any patent or other right, and makes no representation that the circuits are free of patent infringement. charts and schedules contained herein reflect representative operating parameters, and may vary depending upon a user?s specific application. wh ile the information in this publication has been carefully checked, alta analog, inc. shall not be liable for any damages arising as a result of any error or omission. alta analog, inc. does not recommend the use of any of its products in life support or a viation applications where the failure or malfunction of the product can reasonably be expected to cause any failure of either system or to significantly affect their safety or effectiveness. products are not authorized for use in such applications unless alta analog, inc. receives written assurances, to its satisfaction, that: (a) the risk of injury or damage has been minimized; (b) the user assumes all such risks; and (c) potential liability of alta analog, inc. is adequately protected under the circumst ances. this document supersedes all previous versions. ? copyright 2004 alta analog, inc.
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