LM8207MTX/NOPB National Semiconductor, LM8207MTX/NOPB Datasheet
LM8207MTX/NOPB
Specifications of LM8207MTX/NOPB
Related parts for LM8207MTX/NOPB
LM8207MTX/NOPB Summary of contents
Page 1
... In combination with the internal amplifier, the reference voltage can be programmed to voltages up to the positive rail. The LM8207 is offered in a 48-pin TSSOP package. TFT Panel Block Diagram © 2005 National Semiconductor Corporation Driver + Voltage Reference COM Features n Gamma buffers 1-2 swing to V ...
Page 2
... Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. ESD Tolerance (Note 3) Human Body Machine Model Supply Voltage ( Storage Temperature Range Junction Temperature (Note 4) 16V Electrical Characteristics Unless otherwise specified, all limits guaranteed for T Buffers) ...
Page 3
Electrical Characteristics Unless otherwise specified, all limits guaranteed for T Buffers). Boldface limits apply at the temperature extremes. (Note 5) Symbol Parameter I _Gamma Linear Output Current OUT (Note 10) PSRR Power Supply Rejection Ratio V Driver COM BW_V ...
Page 4
Electrical Characteristics Note 6: All limits are guaranteed by design or statistical analysis. Note 7: Typical values represent the parametric norm at the time of characterization. Note 8: Slew Rate is measured for Note ...
Page 5
Pin Descriptions (Continued) 22, IN_V COM 25 OUT_V COM 26, OUT_18 29 OUT_17 30 OUT_16 31 OUT_15 32 OUT_14 33 OUT_13 34 OUT_12 35 OUT_11 36 OUT_10 OUT_9 39 OUT_8 40 OUT_7 ...
Page 6
Typical Performance Characteristics specified. Output Voltage Swing (Negative rail) Voltage Drop vs. Output Current (V Voltage Drop vs. Output Current (Gamma Buffer) www.national.com 25˚ 16V Output Voltage Swing (Positive rail) 20137907 Buffer) ...
Page 7
Typical Performance Characteristics specified. (Continued) Offset Voltage vs. Supply Voltage (Gamma Buffer) Recovery Time (V Buffer) Negative Slope COM (C = 100 pF) L Large Signal Transient Response (V Negative Slope (C = 100 pF 25˚C, ...
Page 8
Typical Performance Characteristics specified. (Continued) Frequency Response for Various Temperature (V Buffer) COM Gain/Phase (Gamma Buffer 100 pF) L Recovery Time (Gamma Buffer 3-16) Negative Slope (C = 100 pF) L www.national.com 25˚ ...
Page 9
Typical Performance Characteristics specified. (Continued) Large Signal Transient Response (Gamma Buffer 3-16) Negative slope (C = 100 pF) L Frequency Response for Various Load (Gamma Buffer) Gain/Phase (Gamma Buffer 100 pF 25˚ ...
Page 10
Typical Performance Characteristics specified. (Continued) Supply Current vs. Supply Voltage Voltage Reference vs. Supply Voltage www.national.com 25˚ 16V Voltage Reference vs. Output Current 20137939 Voltage Reference PSRR (Line Regulation) 20137936 10 = ...
Page 11
Application Section INTRODUCTION The performance capabilities of TFT-LCD’s increase rapidly, with constant improvements such as larger sizes, higher resolution, and greater brightness. Today’s LCD’s have screen resolutions of over 1 Mega pixel and higher. The LM8207 can be used to ...
Page 12
Application Section (Continued) Figure 3 shows how the display information is refreshed. Using the row and column drivers, one pixel is addressed at the display. The column driver receives the digital color data from the timing controller. The corresponding gamma ...
Page 13
Application Section (Continued) FIGURE 4. Typical Application Circuit for V To calculate the output voltage of the Voltage Reference Amplifier (OUT_V ) use the following equation: REF As can be seen in the Electrical Characteristics Table on page 3, I ...
Page 14
Application Section (Continued) FIGURE 7. Voltage Reference Headroom vs. Load Current GAMMA BUFFERS This section gives an overview for the applications of the gamma buffers and also defines the gamma correction curve. Specifications for the buffers are derived from their ...
Page 15
Application Section (Continued) FIGURE 9. Typical TFT Display Application Diagram Using the LM8207 The values of the resistors in the gamma correction curve are calculated such that a current flows in the resistor chain. Where x is ...
Page 16
Application Section (Continued) TABLE 1. Resistor Values for Defining the Gamma Correction Curve Gamma Curve Definition VGMA VGMA Voltage Calculated Resistance (Ω) Node 1 11.59 210 2 11.38 2200 3 9.18 670 4 8.51 670 5 7.84 430 6 7.41 ...
Page 17
Application Section (Continued) V BUFFER COM The V buffer supplies a common voltage to the back COM plate of all the pixels in a TFT panel. When column drivers write to the pixels, current pulses will occur onto the V ...
Page 18
Application Section (Continued) www.national.com FIGURE 12. LM8207 Configuration 18 20137929 ...
Page 19
... Each optimal value can be achieved by using two series resistors for fine-tuning. • The V COM National Semiconductor’s LM8342 programmable V calibrator, or using an external supply. • For testing, an additional dummy load can be connected to all outputs of the gamma buffers. will be 49˚C. ...
Page 20
Application Section (Continued) www.national.com FIGURE 13. Schematic LM8207 Evaluation Board 20 20137950 ...
Page 21
Application Section (Continued) FIGURE 14. Layout of LM8207 Evaluation Board (Actual Size) FIGURE 15. Layout of LM8207 Evaluation Board (Actual Size) LAYOUT RECOMMENDATIONS A proper layout is necessary for optimum performance of the LM8207. A low impedance and clean ground ...
Page 22
... BANNED SUBSTANCE COMPLIANCE National Semiconductor manufactures products and uses packing materials that meet the provisions of the Customer Products Stewardship Specification (CSP-9-111C2) and the Banned Substances and Materials of Interest Specification (CSP-9-111S2) and contain no ‘‘Banned Substances’’ as defined in CSP-9-111S2. ...