LM8400 National Semiconductor, LM8400 Datasheet
LM8400
Related parts for LM8400
LM8400 Summary of contents
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... In the Devices included in this datasheet: Operating Brownout Device Voltage Voltage LM8300 2.7 to 2.9 V LM8400 Brownout LM8500 5 V 4.17V to 4.5V Features KEY FEATURES n Supports 4 wire resistive touch panels n Low power standby current typically less than 2 µ ...
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... Block Diagram * This pin is available in the LM8500 unused in the LM8300/LM8400. Ordering Information LM Family and Feature Set Indicator 8300 = Low Brownout Voltage 8400 = No Brownout 8500 = High Brownout Voltage www.national.com Part Numbering Scheme 8300 H No. Of Pins Pin LQ = LLP Pin MT = TSSOP ...
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General Description ............................................................................................................................................ 1 Features ............................................................................................................................................................. 1 Block Diagram .................................................................................................................................................... 2 Ordering Information .......................................................................................................................................... 2 Connection Diagrams ......................................................................................................................................... 4 2.0 Pin Descriptions ........................................................................................................................................... 5 Absolute Maximum Ratings ............................................................................................................................... 7 3.0 Electrical Characteristics .............................................................................................................................. 7 4.0 Functional Description .................................................................................................................................. 8 4.1 ...
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... See NS Package Number V44A * This pin is available in the LM8500 unused in the LM8300/LM8400. Top View LLP Package See NS Package Number LQA44A www.national.com 20037202 * This pin is available in the LM8500 unused in the LM8300/LM8400. Top View TSSOP Package See NS Package Number MTD48 20037203 4 20037204 ...
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Pin Descriptions Pin Name Direction RESET I DTR I WD_OUT O 1 CLK_SET I 2 Unused 2 Unused 2 Unused 2 Unused OSC_OUT O OSC_IN I 2 Unused 2 Unused UART_TX O UART_RX I SHUTDOWN I 2 Unused 2 ...
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Pin Descriptions Pin Name Direction 2 Unused LED Output 2 Unused 2 Unused 2 Unused Note 1: This is available in the LM8500 only. Note 2: These pins are for future functional expansions. www.national.com (Continued) Pinouts for 44- and ...
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... Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Supply Voltage ( Voltage at Any Pin Total Current into V Pin (Source) CC 3.0 Electrical Characteristics TABLE 1. DC Electrical Characteristics (0˚C ≤ T Datasheet min/max specification limits are guaranteed by design, test, or statistical analysis. ...
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... RESET — Reset pin. When pulled low, a manual reset is executed. For normal operation, this pin must be pulled high. Under no circumstances should the pin be left floating. Note: For the LM8400, an external reset must be used as outlined in the Brownout Reset section. TTL_TX — UART transmit pin. The signal is inverted for use with standard RS-232 drivers. TTL_RX — ...
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Functional Description WD_Out — Watch dog output. For correct operation, this pin should be connected to the RESET pin. OSC_OUT — Clock oscillator output pin. OSC_IN — Clock oscillator input pin GND — Digital Ground AGND — Analog ground ...
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Functional Description Command Byte 1 Byte 2 Set max delta $BC $00-$ pixels from predicted coordinate) Set calibration $BD 4.3.3 points Advanced Command Bytes Descriptions Set minimum $BE $00-$7F pressure Toggle $A0 disable/enable external ...
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Functional Description $B2: Read software version number Reply Byte #1: $C7 (Software version number) Byte #2: First byte in version number, year 20 (00-99) Byte #3: Second byte in version number, month (1-12) Byte #4: Third byte in version ...
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Functional Description The default setting is Echo mode disabled. $A4: Toggle disable/enable pressure measurement Reply Byte #1: $CA (Acknowledge) Byte # now disabled now enabled) The pressure measurement sets the touch screen to also sample ...
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Power Save Mode (Low Power Stand-by) The power consumption of the controller can be minimized by enabling the low power stand by mode. The power save mode can be controlled internally by sending a command of $A2 to the ...
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... The device is initialized when the RESET pin is pulled low or the On-chip Brownout Reset is activated. The Brownout Reset feature is not available on the LM8400. The RESET input initializes the device when pulled low. The RESET pin must be held low for a minimum of 0.5µs for the LM8500 and a minimum of 1.5µ ...
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... LM8300 low voltage range. bor LM8400, BOR is disabled. Refer to the device specifications for the actual V ages. High brownout voltage devices are guaranteed to operate at 10MHz down to the high brownout voltage. Low brownout voltage devices are guaranteed to operate at 3.33MHz down to the low brownout voltage ...
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Calibration (Continued) FIGURE 5. Two Points Calibration Mapping FIGURE 6. Five Points Calibration Mapping FIGURE 7. Thirteen Points Calibration Mapping www.national.com TABLE 4. Two Points Calibration Calibration point Theoretical X-value Theoretical Y-value 1 127 2 895 TABLE 5. Five ...
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Calibration (Continued) 9.1 General Calibration Procedures Calibration is invoked by sending a command byte of $BD followed by a command byte to the device. The command byte is broken into two parts: the high nibble states the number of ...
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Calibration (Continued) 9.2 Calibration Procedures with Coordinates Checking Enabled calibration with coordinates checking enabled, first ensure the Calibration Coordinates Checking is enabled on the device. This can be accomplished by sending a com- mand byte of ...
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... Physical Dimensions inches (millimeters) unless otherwise noted Order Number LM8300HLQ9 or LM8400HLQ9 or LM8500HLQ9 Order Number LM8300IMT9 or LM8400IMT9 or LM85009IMT9 LLP Package (LQA) NS Package Number LQA44A TSSOP Package (MTD) NS Package Number MTD48 19 www.national.com ...
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... Physical Dimensions Order Number LM8300HVA9 or LM8400HVA9 or LM8500HVA9 LIFE SUPPORT POLICY NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or ...