AS1108-WL ams, AS1108-WL Datasheet
AS1108-WL
Specifications of AS1108-WL
Related parts for AS1108-WL
AS1108-WL Summary of contents
Page 1
... General Description The AS1108 is a compact display driver for 7-segment numeric displays digits. The device can be programmed via SPI, QSPI, and Microwire as well as a conventional 4-wire serial interface. ...
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... Serial-Clock Input. 10MHz maximum rate. Data is shifted into the internal shift register on the rising edge of this pin. Data is clocked out of DOUT on the falling edge of this pin. On the AS1108 SPI-enabled, the CLK input is active only while pin LOAD/CSN is low. Seven Segment and Decimal Point Drive Lines. 8 seven-segment drives and decimal point drive that source current to the display ...
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... The reflow peak soldering temperature (body temperature) is specified according to IPC/JEDEC J-STD-020D “Moisture/Reflow Sensitivity Classification for non-hermetic Solid State Surface Mount Devices”. 2. Specified according JESD22-B106 “Resistance to Soldering Temperature for Through-Hole Mounted Devices”. 3. Norm: MIL 883 E method 3015. 4. Norm: JEDEC 17. www.austriamicrosystems.com/LED-Driver-ICs/AS1108 Min Max Units V -0 ...
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... Parameter CLK Clock Period CLK Pulse Width High CLK Pulse Width Low CSMFall-to-CLK Rise Setup Time (AS1108 SPI-programmed) CLK Rise-to -LOAD/CSN Rise Hold Time DIN Setup Time DIN Hold Time Output Data Propagation Delay LOAD Rising Edge-to-Next Clock Rising Edge ...
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... SET 20kΩ SET 40kΩ SET 0.5 1 1.5 2 2.5 3 3.5 V (V) OUT www.austriamicrosystems.com/LED-Driver-ICs/AS1108 Figure 4. Scan Frequency vs. V 1960 1940 1920 1900 1880 1860 1840 1820 1800 80 2 Figure 6. I vs. V SEG OUT ...
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... Datasheet - Figure 9. I vs. R SEG SET 2.4V OUT OUT = OUT 1.7V OUT Ω SET www.austriamicrosystems.com/LED-Driver-ICs/AS1108 70 80 Revision 2. ...
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... Register Address (see Table 7) MSB Initial Power-Up On initial power-up, the AS1108 registers are reset to their default values, the display is blanked, and the device goes into shutdown mode. All registers should be programmed for normal operation at this time. Note: The default settings enable only scanning of one digit; the internal decoder is disabled and the Intensity Control Register (see page 11) is set to the minimum values ...
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... When entering or leaving shutdown mode, the Feature Register is reset to its default values (all 0s) when Shutdown Register bit D7 (page When bit the Feature Register is left unchanged when entering or leaving shut- down mode. Note: If the AS1108 is used with an external clock, Shutdown Register bit D7 should be set to 1 when writing to the Shutdown Register. Digit- and Control-Registers The AS1108 contains four Digit-Registers and six control-registers, which are listed in Table 7 ...
Page 9
... turns the decimal point on). Table 10 lists the code-B font; Table 11 lists the HEX font. When no-decode mode is selected, data bits D7:D0 of the Digit-Registers correspond to the segment lines of the AS1108. Table 12 shows the 1:1 pairing of each data bit and the appropriate segment line. Table 9. Decode Enable Register Format (Address (HEX) = 0xX9)) ...
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... DP Display-Test Register (0xXF) The AS1108 can operate in two modes: normal mode and display test mode. In display test mode all LEDs are switched on at maximum brightness (duty cycle is 15/16). The device remains in display-test mode until the Display- Test Register is set for normal operation. ...
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... Table 15. Scan-Limit Register Format (Address (HEX) = 0xXB)) Scan Limit Display digit 0 only (see Table 16) Display digits 0:1 (see Table 16) Display digits 0:2 (see Table 16) Display digits 0:3 Table 16. Maximum Segment Current for 1-, 2-, or 3-Digit Displays Number of Digits Displayed www.austriamicrosystems.com/LED-Driver-ICs/AS1108 . SET Register Data ...
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... The No-Op Register is used when multiple AS1108 devices are cascaded in order to support displays with more than 4 digits. The cascading must be done in such a way that all DOUT pins are connected to DIN of the next AS1108 (see Figure 12 on page 15). The LOAD/CSN and CLK signals are connected to all devices. ...
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... Datasheet - Typical Application Supply Bypassing and Wiring In order to achieve optimal performance the AS1108 should be placed very close to the LED display to minimize effects of electromagnetic interference and wiring inductance. Furthermore, a 10µF electrolytic and a 0.1µF ceramic capacitor should be connected between pins V avoid power supply ripple (see Figure 12 on page 15) ...
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... SET I (mA) SEG 1.5 2.0 40 11.35kΩ 11.12kΩ 30 15.4kΩ 15.1kΩ 20 23.6kΩ 23.1kΩ 10 48.9kΩ 47.8kΩ Table 24. Package Thermal Data Package Thermal Resistance ( 20 Narrow DIP 20 Wide SOIC www.austriamicrosystems.com/LED-Driver-ICs/AS1108 = 4.0V (Continued (V) LED 2.0 2.5 16.6kΩ 15.6kΩ 34.5kΩ 32.5kΩ (V) LED 2.5 3.0 10.84kΩ 10.49kΩ 14.7kΩ 14.4kΩ 22.6kΩ ...
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... GND GND Cascading Drivers If more than 4 digits or 32 LEDs are needed recommended to use the AS1106/AS1107, although several AS1108 devices can be cascaded. The example in Figure 4 drives 2 dot matrix digits using a 4-wire microprocessor interface. All Scan-Limit Registers should be set to the same value so that one display will not appear brighter than the other. ...
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... AS1108 Datasheet - Package Drawings and Markings The AS1108 is available in a PDIP 20-pin Figure 13. PDIP 20-pin Package 1. For more Information on the PDIP 20-pin package www.austriamicrosystems.com/LED-Driver-ICs/AS1108 1 and a SOIC 20-pin package. ...
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... Lead coplanarity should 0.10mm (.004”) max. 2. Package surface finishing: (2.1) Top: matte (charmilles #18-30). (2.2) All sides: matte (charmilles #18-30). (2.3) Bottom: smooth or matte (charmilles #18-30). 3. All dimensions exclusive of mold flash, and end flash from the pack- age body shall not exceed 0.24mm (0.10”) per side (D). www.austriamicrosystems.com/LED-Driver-ICs/AS1108 Millimeters Symbol Min A 2.44 A1 ...
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... AS1108 Datasheet - Ordering Information The AS1108 is available as the standard products shown in Table 25. Table 25. Ordering Information Ordering Code Description AS1108PL* 4-Digit LED Display Driver AS1108WL 4-Digit LED Display Driver AS1108WL-T 4-Digit LED Display Driver *) The PDIP 20-pin Package reached end of life ...
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... No obligation or liability to recipient or any third party shall arise or flow out of austriamicrosystems AG rendering of technical or other services. Contact Information Headquarters austriamicrosystems AG Tobelbaderstrasse 30 A-8141 Unterpremstaetten, Austria Tel: +43 (0) 3136 500 0 Fax: +43 (0) 3136 525 01 For Sales Offices, Distributors and Representatives, please visit: http://www.austriamicrosystems.com/contact www.austriamicrosystems.com/LED-Driver-ICs/AS1108 Revision 2. ...