LM8500-REF-01 National Semiconductor, LM8500-REF-01 Datasheet
LM8500-REF-01
Specifications of LM8500-REF-01
Related parts for LM8500-REF-01
LM8500-REF-01 Summary of contents
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... Devices included in this datasheet: Operating Brownout Device Voltage Voltage LM8300 2.7 to 2.9 V LM8500 5 V 4.17V to 4.5V 2.0 Features KEY FEATURES n Supports 4 wire resistive touch panels n Low power standby current typically less than 2 µA at 5.5V n Maximum speed of 500 coordinate pairs per second ...
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... Block Diagram * This pin is available in the LM8500 unused in the LM8300. 4.0 Ordering Information LM Family and Feature Set Indicator 8300 = Low Brownout Voltage 8500 = High Brownout Voltage www.national.com Part Numbering Scheme 8300 H No. Of Pins Pin LQ = LLP Pin MT = TSSOP VA = PLCC 2 20037201 VA 9 Package Type Temperature +70˚ ...
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General Description ..................................................................................................................................... 1 2.0 Features ....................................................................................................................................................... 1 3.0 Block Diagram .............................................................................................................................................. 2 4.0 Ordering Information .................................................................................................................................... 2 5.0 Connection Diagrams ................................................................................................................................... 4 6.0 Pin Descriptions ........................................................................................................................................... 5 7.0 Absolute Maximum Ratings ......................................................................................................................... 7 8.0 Electrical Characteristics .............................................................................................................................. 7 ...
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... Plastic Chip Package See NS Package Number V44A * This pin is available in the LM8500 unused in the LM8300. Top View LLP Package See NS Package Number LQA44A www.national.com 20037202 * This pin is available in the LM8500 unused in the LM8300. 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 Name Direction 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 48-Pin Packages (Continued) Pin Description Optional LED output, low when running, high in halt-mode 6 44-Pin LLP ...
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... Absolute Maximum Ratings 3) 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 8.0 Electrical Characteristics DC Electrical Characteristics (0˚C ≤ T Datasheet min/max specification limits are guaranteed by design, test, or statistical analysis. ...
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... MHz. If the pin is tied low, then the operating frequency is set to 3.3 MHz. Note: This is available on the LM8500 only. SHUTDOWN — This is the external shut down pin. When pulled low, the controller goes into power saving mode. This selection pin state has higher priority than the internal power save mode settings ...
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Functional Description LED — Optional LED output. When the controller is oper- ating in normal (non power save) mode, a low is output to the pin. When the controller is in power save mode, a high is output to ...
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... Note: This is available in the LM8500 only. $B1: Read parameters Reply Byte #1: $CA (Acknowledge) Reply Byte #2: First byte in software version number, $CA $00, $01 ...
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Functional Description Byte #11: Number of calibration coordinates ( 13) Byte #12: Toggle-flags: Bit #5: calibration coordinates check (0=disabled, 1=enabled) Bit #4: Pressure measurement 1=enabled) Bit #3: Echo mode (0=disabled, 1=enabled) Bit #2: Self Power-Down mode ...
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Functional Description lines. This option can be used in high noise environments to significantly improve performance and accuracy of the touch screen controller. The default setting is filter path enabled. $A2: Toggle disable/enable self-power down Reply Byte #1: $CA ...
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... UART, the wake up command byte must be sent, followed by a minimum time delay of 1ms for the LM8500 and 3ms for the LM8300 before sending any command byte. The delay time is needed to allow the oscil- lator to restart and stabilize. Table 2. Startup Times shows the average startup time for a given operating frequency ...
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... At this time the brownout circuit becomes active and holds the device in RESET. As the supply passes a level of about 1.8V, a delay of about 3 ms (td) is started and t preset with 120-128 µs for the LM8500 or 360-384 µs for the LM8300. Once starts to count down ...
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... CC output of the brownout reset detector will always preset t FIGURE 4. Brownout Reset Operation counts down a value between 120-128µs for the LM8500 and 360-384µs id for the LM8300. At this time, the internal reset will be gener- ated. The device has a built in watchdog monitoring module to prevent runaway code ...
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Calibration (Continued) in Table 3. Two Points Calibration, Table 4. Five Points Calibration, and Table 5. Thirteen Points Calibration respec- tively. FIGURE 5. Two Points Calibration Mapping FIGURE 6. Five Points Calibration Mapping FIGURE 7. Thirteen Points Calibration Mapping ...
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Calibration (Continued) FIGURE 8. Calibration Procedures with Coordinates Checking Enabled 14.2 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 ...
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Calibration (Continued) send a reply byte of $CC to the TS driver. At this point, the TS driver should either notify the user to redo the calibration point or automatically redo the calibration again. If the self- test was ...
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... Physical Dimensions inches (millimeters) unless otherwise noted LLP Package (LQA) Order Number LM8300HLQ9 or LM8500HLQ9 NS Package Number LQA44A TSSOP Package (MTD) Order Number LM8300IMT9 or LM85009IMT9 NS Package Number MTD48 19 www.national.com ...
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... National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications. inches (millimeters) unless otherwise noted (Continued) Plastic Leaded Chip Carrier (VA) Order Number LM8300HVA9 or LM8500HVA9 NS Package Number V44A 2. A critical component is any component of a life ...