MAX7325 Maxim, MAX7325 Datasheet
MAX7325
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MAX7325 Summary of contents
Page 1
... I/O ports, and enables or disables internal 40kΩ pullups in groups of four ports. The MAX7325 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 V+ Current..................................................................50mA 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 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 Output Data Valid Port Input Setup Time ...
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I C Port Expander with 8 Push-Pull and 8 Open-Drain I/ +25°C, unless otherwise noted.) A STANDBY CURRENT vs. TEMPERATURE 2.0 1.8 1.6 1.4 1.2 1 +3. +2.5V 0.8 0.6 0 ...
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... _______________________________________________________________________________________ C Port Expander with 8 Push-Pull and 8 Open-Drain I/Os The MAX7325 is set to two (see Tables 2 and 3) using the address select inputs AD0 and AD2, and is accessed over an I face up to 400kHz. The eight outputs and eight I/Os have different slave addresses. The eight push-pull out- puts have the 101xxxx addresses and the eight inputs have addresses with 110xxxx ...
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... Yes — 12 Offers maximum versatility for automatic input monitoring. An interrupt mask selects which inputs cause an interrupt on transitions, and transition flags identify which inputs have changed (even if only for a transient) since the ports were last read. ...
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... I/O state for the ports, and select which inputs have pullup resistors. Internal pullups and power-up default states are set in groups of four (see Table 2). The MAX7325 slave address is determined on each I Initial Power-Up transmission, regardless of whether the transmission is actually addressing the MAX7325. The MAX7325 distin- ...
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... SDA and SCL behavior. If one of the other 12 address combinations is used, an unexpected combination of pullups might be asserted until the first I sarily the MAX7325) is put on the bus, and an unex- pected combination of ports can initialize as logic-low outputs instead of inputs or logic-high outputs. PORT POWER-UP DEFAULT ...
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... I edge of every MAX7325 read and write access. The previ- ous port transition flags are read through the serial interface as the second byte of a 2-byte read sequence. ...
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... The master initiates all data transfers to and from the MAX7325 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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... A 2-byte read from the I/O ports (P0–P7) of the MAX7325 returns the status of the eight I/O ports (as for a single-byte read), followed by the transition flags. Again, the internal transition flags and the INT output ...
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... SCL PORT t IV INT OUTPUT Figure 6. Reading Open-Drain Ports of the MAX7325 (1 Data Byte) 12 ______________________________________________________________________________________ 2 C STOP A read from the open-drain I/O ports of the MAX7325 starts with the master transmitting the port group’s slave address with the R/W bit set to high. The ...
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... MAX7325 SLAVE ADDRESS SCL PORTS t IV INT OUTPUT Figure 7. Reading Open-Drain Ports of the MAX7325 (2 Data Bytes) ACKNOWLEDGE FROM MAX7325 S MAX7325 SLAVE ADDRESS SCL Figure 8. Reading Push-Pull Ports of MAX7325 ______________________________________________________________________________________ C Port Expander with 8 Push-Pull and 8 Open-Drain I/Os A read from the push-pull ports of the MAX7325 starts with the master transmitting the group’ ...
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... Writing the MAX7325 A write to either output port groups of the MAX7325 starts with the master transmitting the group’s slave address with the R/W bit set low. The MAX7325 acknowledges the slave address and samples the ports during the acknowledge bit ...
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... Any combination of outputs can be used as part of a load-sharing design because any combination of ports can be set or cleared at the same time by writing to the MAX7325. Do not exceed a total sink current of 100mA for the device. The MAX7325 must be protected from the negative- voltage transient generated when switching off induc- ...
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... INT PROCESS: BiCMOS SDA 22 SCL 21 AD0 20 O15 19 O14 18 O13 17 O12 16 O11 15 O10 Typical Application Circuit 3.3V V+ SCL MAX7325 SDA O15 RST O14 INT O13 O12 O11 OUTPUT O10 OUTPUT O9 OUTPUT O8 OUTPUT P7 INPUT/OUTPUT P6 INPUT/OUTPUT P5 INPUT/OUTPUT P4 INPUT/OUTPUT P3 INPUT/OUTPUT P2 INPUT/OUTPUT AD0 P1 INPUT/OUTPUT ...
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... I (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.) ______________________________________________________________________________________ C Port Expander with 8 Push-Pull and 8 Open-Drain I/Os Package Information PACKAGE OUTLINE, 12, 16, 20, 24, 28L THIN QFN, 4x4x0.8mm 1 E 21-0139 ...
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... I C Port Expander with 8 Push-Pull and 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.) 18 ______________________________________________________________________________________ Package Information (continued) PACKAGE OUTLINE, 12, 16, 20, 24, 28L THIN QFN, 4x4x0.8mm ...
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... For the latest package outline information www.maxim-ic.com/packages.) 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. ...