MAX6957 MAXIM [Maxim Integrated Products], MAX6957 Datasheet
MAX6957
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MAX6957 Summary of contents
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... Schmitt logic input with optional internal pullup. Seven ports feature configurable transition detection logic, which generates an interrupt upon change of port logic level. The MAX6957 is controlled through an SPI™-compatible 4-wire serial interface. The MAX6957AAX and MAX6957AGL have 28 ports and are available in 36-pin SSOP and 40-pin QFN packages, respectively ...
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LED Display Driver and I/O Expander ABSOLUTE MAXIMUM RATINGS Voltage (with Respect to GND) V+ .............................................................................-0.3V to +6V All Other pins................................................-0.3V to (V+ + 0.3V) P4–P31 Current ................................................................±30mA GND Current .....................................................................800mA Continuous Power ...
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LED Display Driver and I/O Expander ELECTRICAL CHARACTERISTICS (continued) (Typical Operating Circuit 2.5V to 5.5V, T PARAMETER SYMBOL Port Sink Current Output Short-Circuit Current I OLSC Port Drive LED Sink Current, ...
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LED Display Driver and I/O Expander __________________________________________Typical Operating Characteristics (R = 39kΩ +25°C, unless otherwise noted.) ISET A OPERATING SUPPLY CURRENT vs. TEMPERATURE 0. 2.5V TO 5.5V 0.36 NO ...
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... This example requires two MAX6957s, with one digit being driven by both devices, half by one MAX6957, half by the other (digit 4 in this example). The two drivers are static, and therefore do not need to be synchronized. The MAX6957 sees CA digits as multiple discrete LEDs ...
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... Active-high logic output Schmitt logic input Schmitt logic input with pullup When the MAX6957 is in shutdown mode, all ports are forced to inputs, and the pullup current sources are turned off. Data in the port and control registers remain unaltered so port configuration and output levels are restored when the MAX6957 is taken out of shutdown ...
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... SCLK. Note that the SPI protocol expects DOUT to be high impedance when the MAX6957 is not being accessed; DOUT on the MAX6957 is never high impedance. SCLK and DIN may be used to transmit data to other peripherals, so the MAX6957 ignores all activity on _______________________________________________________________________________________ INTENSITY TEST CONFIGURATION ...
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... VIRTUAL SEGMENTS P10 P11 P12 P13 P14 P15 P16 P17 P18 P19 P20 P21 P22 P23 P24 P25 P26 P27 P28 P29 P30 P31 Figure 2. Two MAX6957s Controlling Seven 7-Segment Displays CS t CSS t CSH SCLK ...
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... MAX6957 between taking CS low and taking CS high again. In this case, only the last 16 bits clocked into the MAX6957 are retained. Any register data within the MAX6957 may be read by sending a logic high to bit D15. The sequence is: 1) Take SCLK low. 2) Take CS low (this enables the internal 16-bit shift register). 3) Clock 16 bits of data into DIN— ...
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... Ports are monitored regardless of their I/O configuration, both input and output. The MAX6957 maintains an internal 7-bit snapshot reg- ister to hold the comparison copy of the logic states of ports P24 through P30. The snapshot register is updat- ed with the condition of P24 through P31 whenever the ...
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LED Display Driver and I/O Expander Table 3. Register Address Map REGISTER No-Op Global Current Configuration Transition Detect Mask Display Test Port Configuration P7, P6, P5, P4 Port Configuration P11, P10, P9, P8 ...
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LED Display Driver and I/O Expander Table 3. Register Address Map (continued) REGISTER Port 11 only Port 12 only Port 13 only Port 14 only Port 15 only Port 16 only Port 17 ...
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... LED with a 2.4V forward-voltage drop when operated from a supply voltage of at least 3.0V. The minimum voltage drop across the internal LED drivers is there- fore (3.0V - 2.4V) = 0.6V. The MAX6957 can sink 28 x 24mA = 672mA when all outputs are operating as LED segment drivers at full current 3.3V supply, a MAX6957 dissipates (3 ...
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LED Display Driver and I/O Expander P31 GPIO INPUT CONDITIONING P30 GPIO/PORT OUTPUT LATCH GPIO INPUT CONDITIONING P29 GPIO/PORT OUTPUT LATCH GPIO INPUT CONDITIONING P28 GPIO/PORT OUTPUT LATCH GPIO INPUT CONDITIONING P27 GPIO/PORT ...
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LED Display Driver and I/O Expander Table 4. Power-Up Configuration REGISTER POWER-UP CONDITION FUNCTION Port Register LED Off; GPIO Output Low Bits Global 1/16 (minimum on) Current Shutdown Enabled Configuration ...
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LED Display Driver and I/O Expander Table 5. Configuration Register Format ADDRESS CODE FUNCTION (HEX) Configuration Register 0x04 X = Don’t care bit. Table 6. Shutdown Control (S Data Bit D0) Format ADDRESS ...
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LED Display Driver and I/O Expander Table 9. Global Segment Current Register Format (continued) LED DRIVE TYPICAL SEGMENT FRACTION CURRENT (mA) 6/16 9 7/16 10.5 8/16 12 9/16 13.5 10/16 15 11/16 16.5 ...
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... The MAX6957 operates with power-supply voltages of 2 (82Ω ✕ 2.5V to 5.5V. Bypass the power supply to GND with a 0.047µF capacitor as close to the device as possible. Add a 1µF capacitor if the MAX6957 is far away from the board's input bulk decoupling capacitor HEX CODE ...
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LED Display Driver and I/O Expander Table 12. Odd Individual Segment Current Format SEGMENT LED CONSTANT DRIVE CURRENT WITH FRACTION R = 39kΩ (mA) ISET 1/16 1.5 2/16 3 3/16 4.5 4/16 6 ...
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... LED Display Driver and I/O Expander Pin Configurations (continued) TOP VIEW ISET 1 GND 2 GND 3 DOUT P12 P13 8 MAX6957 P10 9 P14 10 P11 11 P15 12 P16 13 P17 14 P18 15 P19 16 P20 17 P21 18 SSOP 20 ______________________________________________________________________________________ TRANSISTOR COUNT: 30,316 PROCESS: CMOS 36 V+ ...
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... P25 P22 20 P24 P23 GND 26 P7 GND 5 P8 ISET P10 11 DIN P11 U2 6 SCLK P12 8 CS MAX6957AAX P13 10 DOUT P14 12 P15 13 P31 P16 14 P30 P17 15 P29 P18 16 P28 P19 17 P27 P20 18 P26 P21 19 P25 P22 20 P24 P23 3V ...
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LED Display Driver and I/O Expander (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information www.maxim-ic.com/packages.) 22 ______________________________________________________________________________________ Package Information ...
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LED Display Driver and I/O Expander (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information www.maxim-ic.com/packages.) Maxim cannot assume responsibility ...