MAX7321 Maxim, MAX7321 Datasheet
MAX7321
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MAX7321 Summary of contents
Page 1
... I/O ports, and enables or disables internal 40kΩ pullups in groups of four ports. The MAX7321 is one device in a family of pin-compatible port expanders with a choice of input ports, open-drain I/O ports, and push-pull output ports (see Table 1). ...
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... Total GND Current ...........................................................100mA Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability ...
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I C Port Expander with 8 Open-Drain I/Os PORT AND INTERRUPT INT TIMING CHARACTERISTICS (V+ = +1.71V to +5.5V -40°C to +125°C, unless otherwise noted. Typical values are +3.3V PARAMETER SYMBOL Port ...
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I C Port Expander with 8 Open-Drain I/ +25°C, unless otherwise noted.) A STANDBY CURRENT vs. TEMPERATURE 2 0kHz SCL 1.8 1.6 1.4 1 +5.0V 1 +3. +2.5V 0.8 ...
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... The outputs drive loads connected to supplies up to +5.5V, independent of the MAX7321’s supply voltage. The MAX7321 is set to one (0x60 to 0x6F) using the address select inputs AD0 and AD2, and is accessed over an I 400kHz. The RST input clears the serial interface in ...
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... MAX7321. Any port can be configured as a logic input by setting the port output logic-high (logic-high for an open-drain output is high impedance). When the MAX7321 is read through the serial interface, the actual logic levels at the ports are read back. The open-drain ports offer latching transition detection when used as inputs ...
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... C transaction involving the MAX7321, forcing the MAX7321 into the I dition. A reset does not affect the interrupt output (INT). When the serial interface is idle, the MAX7321 automat- ically enters standby mode, drawing minimal supply current. Slave Address, Power-Up Default Logic Levels, and Input Pullup Selection ...
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... I C transmission (to any device, not neces- sarily the MAX7321) is put on the bus, and an unex- pected combination of ports may initialize as logic-low outputs instead of inputs or logic-high outputs. 8 _______________________________________________________________________________________ DEVICE ADDRESS ...
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... The master initiates all data transfers to and from the MAX7321 and generates the SCL clock that synchronizes the data transfer (Figure 1). SDA operates as both an input and an open-drain out- put. A pullup resistor, typically 4.7kΩ ...
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... Typically, the master reads bytes from the MAX7321, each byte being acknowledged by the mas- ter upon reception with the exception of the last byte. When the master reads 1 byte from the MAX7321 and subsequently issues a STOP condition (Figure 6), the MAX7321 transmits the current port data, clears the change flags, and resets the transition detection ...
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... SCL PORT I INT OUTPUT Figure 6. Reading the MAX7321 (1 Data Byte MAX7321 SLAVE ADDRESS SCL PORTS t IV INT OUTPUT Figure 7. Reading the MAX7321 (2 Data Bytes) ______________________________________________________________________________________ R/W PORT SNAPSHOT INT REMAINS HIGH UNTIL STOP CONDITION ...
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... Translation from Higher or Lower The MAX7321’s SDA, SCL, AD0, AD2, RST, INT, and I/O ports P0–P7 are overvoltage protected to +6V indepen- dent of V+. This allows the MAX7321 to operate from a lower supply voltage, such as +3.3V, while the I face and/or any of the eight I/O ports are driven as inputs driven from a higher logic level, such as +5V ...
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... Driving LED Loads When driving LEDs, a resistor must be fitted in series with the LED to limit the LED current to no more than 20mA. Connect the LED cathode to the MAX7321 port, and the LED anode to V+ through the series current- limiting resistor Set the port output low to illumi- LED nate the LED ...
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... I C Port Expander with 8 Open-Drain I/Os Driving Load Currents Higher than 20mA The MAX7321 can be used to drive loads, such as relays, that draw more than 20mA by paralleling out- puts. Use at least one output per 20mA of load current; for example, a 5V, 330mW relay draws 66mA, and therefore, requires four paralleled outputs ...
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... I2C Port Expander with 8 Open-Drain I/Os (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.) ______________________________________________________________________________________ Package Information 15 ...
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... I2C Port Expander with 8 Open-Drain I/Os (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.) E MARKING E/2 AAAA D 0. ______________________________________________________________________________________ Package Information (continued) ( 0.08 C ...
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... NUMBER OF LEADS SHOWN ARE FOR REFERENCE ONLY. 12. WARPAGE NOT TO EXCEED 0.10mm. Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. ...