MAX7370 Maxim, MAX7370 Datasheet
MAX7370
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MAX7370 Summary of contents
Page 1
... Interface and High Level of ESD Protection General Description 2 The MAX7370 I C-interfaced peripheral provides micro- processors with management key switches, with optional GPIO and PWM-controlled LED drivers. The key-switch drivers interface with metallic or resistive switches with on-resistances up to 5kI. Key inputs are monitored statically, not dynamically, to ensure low-EMI operation ...
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... All key switches open, oscillator running keys pressed I Not using GPO or LED configuration SL V POR I KEY V KEY R (Note 4) KEY t START V LED V = 3.3V 1V 10mA output mode MAX7370 = +70° 3.3V +25NC.) (Notes MIN TYP MAX 1.62 3.3 3.6 V 3.3 3 1.8 1.2 28 0.45 0.5 2 2.7 ...
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... CC SOURCE 1.62V and I CC SOURCE 6mA OL SINK f Derived from oscillator clock PWM Input voltage = 5. LEAKAGE 6mA OL SINK C (Notes MAX7370 = 3.3V +25NC.) (Notes MIN TYP MAX 8.6 11.4 9.04 10 10.96 9.5 18.13 21.52 18.47 20 21.34 19. GND - 500 50 100 ...
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... (Notes (Note TIMEOUT IEC 61000-4-2 Air-Gap Discharge IEC 61000-4-2 Contact Discharge Human Body Model = +25°C. Specifications over temperature are guaranteed by design. A and t measured between 0.8V and 2.1V and t R MAX7370 = 3.3V +25NC.) (Notes MIN TYP 0.05 0 1.3 0.6 0.6 0.6 100 1 ...
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... CONSTANT-CURRENT GPIO OUTPUT SINK CURRENT vs. OUTPUT VOLTAGE (COL7–COL4 +85° 3. -40° 3.0 0 0.5 1.0 1.5 2.0 OUTPUT VOLTAGE (V) MAX7370 GPO OUTPUT LOW VOLTAGE vs. SINK CURRENT (COL7–COL4) 120 V = 3.6V CC 100 T = +85° ...
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... Maxim Integrated Products 6 (BUMP SIDE DOWN COL0 11 COL1 10 COL2 COL3 9 GND 8 EP* COL4 MAX7370 Pin Configurations TOP VIEW MAX7370 ROW5 ROW7 COL6 A ROW4 ROW6 COL7 COL4 B GND ROW2 GND COL2 C ROW3 D ROW1 V ...
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... LED ENABLE LOGIC PWM SIGNAL COLUMN ENABLE CURRENT DETECT GPIO ENABLE GPIO INPUT KEY-SCAN LOGIC CONTROL ROW ENABLE ROW DETECT GPIO ENABLE GPIO INPUT POR MAX7370 Pin Description (continued) FUNCTION 3.6V Functional Block Diagram COL0 COL1 CURRENT COL2 ...
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... Interface and High Level of ESD Protection Detailed Description The MAX7370 is a microprocessor peripheral low-noise key-switch controller that monitors key switches with optional autorepeat, and key events that are pre- sented in a 16-byte FIFO. Key-switch functionality can be traded to provide logic inputs. The device ...
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... Interrupt 0xFF mask 2 GPI trigger 0x00 mode 1 GPI trigger 0x00 mode 2 MAX7370 DESCRIPTION GPIO voltages supplied ROW7–ROW0 GPIO voltages supplied COL7–COL0 Debounced input or output values of ROW7–ROW0 Debounced input or output values of COL7–COL0 ...
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... KEY 26 KEY 34 KEY 19 KEY 27 KEY 35 KEY 20 KEY 28 KEY 36 KEY 21 KEY 29 KEY 37 KEY 22 KEY 30 KEY 38 KEY 23 KEY 31 KEY 39 MAX7370 Configuration Register (0x01) Table 8. Debounce Register (0x02) Table 9. Interrupt Register (0x03) Autorepeat Register (0x05) COL4 COL5 COL6 KEY 40 KEY 48 KEY 41 KEY 49 KEY 42 KEY 50 ...
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... When the port is initially programmed as an input, there Autowake is a delay of one debounce period prior to detecting a transition on the input port. This is to prevent a false interrupt from occurring when changing a port from an output to an input. MAX7370 FIFO Overflow The GPIO ports’ inputs CC LA ...
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... Common PWM Ratio register (0x45). New PWM settings take place at the beginning of a PWM cycle, to allow changes from common intensity to individual intensity with 24. Bit D5 enables no interruption in the PWM cycle. MAX7370 2 C timeouts the main GPIO Debounce Configuration Register (0x42) LED Constant-Current Setting Register (0x43) Table 26 ...
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... PWM settings are affected. • Take the part out of sleep mode to cause all ports to fade in. Changing an individual PWM intensity dur- ing fade in automatically cancels that port’s fade and immediately outputs at its newly programmed intensity. MAX7370 Sleep Mode 24. Fade in increases an LED’s PWM intensity LED Fade ...
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... INT. Figure 1 t SU, DAT t SU, STA t HD, DAT t HIGH t F REPEATED START CONDITION MAX7370 2 C timeout, or GPIOs Serial Interface shows the two-wire serial interface timing details BUF t HD, STA ...
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... When the device is transmitting to the master, the master generates the acknowledge bit because the master is the recipient. CHANGE OF DATA DATA VALID ALLOWED MAX7370 3). The data on SDA must remain stable while Acknowledge (Figure P STOP CONDITION ...
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... The first data byte goes into the internal register of the device selected by the command byte If multiple data bytes are transmitted before a STOP condi- tion is detected, these bytes are generally stored in sub- sequent internal registers of the device, because the com- mand-byte address generally autoincrements MAX7370 CLOCK PULSE FOR ACKNOWLEDGE ...
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... Table 4. Autoincrement Rules REGISTER FUNCTION Keys FIFO Autosleep All other key switches (Figure 6). All other GPIOs MAX7370 COMMAND BYTE A P ACKNOWLEDGE FROM MAX7370 ACKNOWLEDGE FROM MAX7370 DATA BYTE 1 BYTE ACKNOWLEDGE FROM MAX7370 ...
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... GHOST-KEY EVENT Figure 10. Valid Three-Key Combinations MAX7370 (Figure 9). Because the key 10). There is no limit on the number of keys Low-EMI Operation . This reduces ...
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... FIRST PEAK RISE TIME ( WITH OF CURRENT DISCHARGE SWITCH (ns) (A) 7 22 MAX7370 Power-Supply Considerations ) to GND with a CC ESD Protection and 6 are taken from the IEC 61000-4-2: CURRENT CURRENT (Q30%) (Q30%) AT 30ns AT 60ns ( ...
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... KEYS FIFO REGISTER DATA Key- FIFO not- release flag MAX7370 Register Tables Key number/key event ...
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... Enable keypress wakeup timeout enabled timeout disabled. MAX7370 FUNCTION 2 C write to this bit. When constant-current PWM is disabled (bit 4 of register 0x40 is low write, autosleep, and autowake all can change this bit. This bit can be read back by I any time for current status ...
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... FIFO-BASED INT Not all zero MAX7370 PRESS DEBOUNCE TIME REGISTER DATA TIME-BASED INT ...
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... REGISTER DATA RESERVED MAX7370 REGISTER DATA AUTOREPEAT DELAY Autorepeat delay AUTOSHUTDOWN TIME D3 ...
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... VALUE FUNCTION 0000 — 0 GPIO function 1 LED driver enable 0 GPIO function 1 LED driver enable 0 GPIO function 1 LED driver enable 0 GPIO function 1 LED driver enable MAX7370 REGISTER DATA COLUMNS ...
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... Set as input pin 1 Set as output pin 0 Set as input pin 1 Set as output pin 0 Set as input pin 1 Set as output pin 0 Set as input pin 1 Set as output pin 0 Set as input pin 1 Set as output pin MAX7370 DEFAULT VALUE DEFAULT VALUE ...
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... Port is an open-drain output 1 Port is a push-pull output 0 Port is an open-drain output 1 Port is a push-pull output 0 Port is an open-drain output 1 Port is a push-pull output 0 Port is an open-drain output 1 Port is a push-pull output MAX7370 DEFAULT VALUE DEFAULT VALUE ...
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... COL3 supplied COL3 supplied COL2 supplied COL2 supplied COL1 supplied COL1 supplied COL0 supplied COL0 supplied MAX7370 DEFAULT VALUE DEFAULT VALUE ...
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... Clear COL4 low 1 Set COL4 high* 0 Clear COL3 low 1 Set COL3 high 0 Clear COL2 low 1 Set COL2 high 0 Clear COL1 low 1 Set COL1 high 0 Clear COL0 low 1 Set COL0 high MAX7370 DEFAULT VALUE DEFAULT VALUE ...
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... GPIO direction 2 register (0x35) 0 Level shifting disabled Level shift between COL1 and ROW1 enabled; 1 direction controlled by GPIO direction 2 register (0x35) 0 Level shifting disabled Level shift between COL0 and ROW0 enabled; 1 direction controlled by GPIO direction 2 register (0x35) MAX7370 DEFAULT VALUE ...
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... D[2:0] = 101 = 4096ms D[2:0] = 110/111 = Undefined REGISTER DATA RESERVED ⋮ MAX7370 DEFAULT VALUE DEBOUNCE TIME ...
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... C timeout has occurred since last read or 0 POR timeout has occurred since last read or POR. This bit is reset to zero when a read is performed 1 on this register timeouts must be enabled for this function to work (see Table 8). MAX7370 DEFAULT VALUE REGISTER DATA COMMON PWM ...
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... Port blink period is 4096ms 110/111 Undefined 00 LED is on for 50% of the blink period 01 LED is on for 25% of the blink period 10 LED is on for 12.5% of the blink period 11 LED is on for 6.25% of the blink period MAX7370 REGISTER DATA PORT PWM ...
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... Interrupt is not masked 1 Interrupt is masked 0 Interrupt is not masked 1 Interrupt is masked 0 Interrupt is not masked 1 Interrupt is masked 0 Interrupt is not masked 1 Interrupt is masked 0 Interrupt is not masked 1 Interrupt is masked 0 Interrupt is not masked 1 Interrupt is masked MAX7370 DEFAULT VALUE DEFAULT VALUE ...
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... Rising-edge-triggered interrupts 1 Rising- and falling-edge-triggered interrupts 0 Rising-edge-triggered interrupts 1 Rising- and falling-edge-triggered interrupts 0 Rising-edge-triggered interrupts 1 Rising- and falling-edge-triggered interrupts 0 Rising-edge-triggered interrupts 1 Rising- and falling-edge-triggered interrupts 0 Rising-edge-triggered interrupts 1 Rising- and falling-edge-triggered interrupts MAX7370 DEFAULT VALUE DEFAULT VALUE ...
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... COL7 I/O COL6 COL5 I/O COL4 I/O COL3 COL2 COL1 COL0 MAX7370 ROW7 ROW6 ROW5 ROW4 ROW3 ROW2 ROW1 ROW0 GND MAX7370 Typical Application Circuit KEY 7 KEY 15 KEY 23 KEY 6 KEY 14 KEY 22 KEY 5 KEY 13 KEY 21 KEY 4 KEY 12 KEY 20 KEY 3 KEY 11 KEY 19 KEY 2 KEY 10 KEY 18 KEY 1 ...
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... Maxim Integrated Products 36 PROCESS: BiCMOS PART MAX7370ETG+ MAX7370EWA+** +Denotes a lead(Pb)-free/RoHS-compliant package. *EP = Exposed. pad. **Future product—contact factory for availability. LAND PATTERN NO. 90-0122 Refer to Application Note 1891 MAX7370 Chip Information Ordering Information TEMP RANGE PIN-PACKAGE -40NC to +85NC 24 TQFN-EP* 25 WLP -40NC to +85NC ...
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... Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 2011 Maxim Integrated Products © DESCRIPTION Maxim is a registered trademark of Maxim Integrated Products, Inc. MAX7370 Revision History PAGES CHANGED — 37 ...