MAX6967 MAXIM [Maxim Integrated Products], MAX6967 Datasheet
MAX6967
Related parts for MAX6967
MAX6967 Summary of contents
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... The DOUT/OSC pin can be configured as either the serial interface data output or optional PWM clock input. The MAX6966 powers up defaulting as DOUT output. The MAX6967 defaults as OSC input. For a similar part without the constant-current controls, refer to the MAX7317 data sheet. LCD Backlights ...
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Constant-Current LED Drivers and I/O Expanders with PWM Intensity Control ABSOLUTE MAXIMUM RATINGS Voltage (with respect to GND) V+ .............................................................................-0.3V to +4V SCLK, DIN, CS, DOUT/OSC.........................-0.3V to (V+ + 0.3V) P_ .............................................................................-0.3V to +8V DC Current into P_ .............................................................24mA ...
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Constant-Current LED Drivers and I/O Expanders with PWM Intensity Control ELECTRICAL CHARACTERISTICS (continued) (Typical Operating Circuit 2.25V to 3.6V, T +25°C.) (Note 1) PARAMETER SYMBOL Input High Voltage (P0–P9, DIN, SCLK, CS, OSC) Input Low Voltage (P0–P9, ...
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Constant-Current LED Drivers and I/O Expanders with PWM Intensity Control TIMING CHARACTERISTICS (Typical Operating Circuit 2.25V to 3.6V, T +25°C.) (Note 1) PARAMETER SYMBOL Internal PWM Clock Frequency External PWM Clock Frequency SCLK Clock Period SCLK Pulse ...
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Constant-Current LED Drivers and I/O Expanders with PWM Intensity Control (T = +25°C, unless otherwise noted.) A STANDBY CURRENT (I ) STBY1 vs. TEMPERATURE 1.2 1 3.6V 1 3.3V 0 2.7V 0.8 0.7 ...
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... OSC Input. Apply a square-wave CMOS clock up to 100kHz as alternate PWM clock source. The MAX6966 powers up with DOUT/OSC defaulting as DOUT output. The MAX6967 powers up with DOUT/OSC defaulting as OSC input. Serial-Data Input. Data from DIN loads into the internal 16-bit shift register on SCLK’s rising ...
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... LED from a port configured as a logic output is unlikely to damage the LED. The MAX6966/MAX6967 are rated for all 10 outputs to carry their maximum 20mA loads at the same time. The port configuration options are shown in BEHAVIOR OUT OF ...
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... GLOBAL CURRENT REGISTER Figure 1. Simplified Schematic of I/O Ports Figure 1 shows the I/O port structure of the MAX6966/ MAX6967. I/O ports default to high impedance on power-up, so LED or other port loads connected draw no current, and ports used as inputs do not load their source signals. Standby Mode and Operating Current ...
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... GPIO output. When shut- down mode is exited, the new GPIO output is unaffect- ed just like any other GPIO outputs. The MAX6966/MAX6967 can be configured so that a relatively long pulse on the CS input brings the driver out of shutdown alternative method to the normal method of writing the configuration register through the serial interface ...
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... The no-op address, 0x20, causes no action when written or read, and is used as a dummy register when accessing one (Table 2). Two MAX6966/MAX6967 out of multiple cascaded devices. COMMAND ADDRESS D15 D14 D13 ...
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... Power-up status sets I/O ports high imped- ance, and puts the device into shutdown mode. This means that any LED (or other) loads are effectively turned off, and the MAX6966/MAX6967 start in its low- est power condition. An internal 32kHz oscillator generates PWM timing. If all output ports are set to static levels, the internal oscil- Table 3 ...
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Constant-Current LED Drivers and I/O Expanders with PWM Intensity Control PWM Timing and Phasing A PWM period comprises 256 cycles of the nominal 32kHz PWM clock (Figure 2). Ports can be set individu- ally to a PWM duty between ...
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Constant-Current LED Drivers and I/O Expanders with PWM Intensity Control Table 4. Configuration Register REGISTER CONFIGURATION Write device configuration Read-back device configuration Shutdown mode (CS run disabled) Put or keep device in shutdown, disable CS run Shutdown mode (CS ...
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... Constant-Current LED Drivers and I/O Expanders with PWM Intensity Control The stagger bit is ideally set or cleared when the MAX6966/MAX6967 are in shutdown. If not, there may be a perceived transient flicker in any PWM-controlled LEDs because the fundamental PWM timing is being changed. Configuration Register The configuration register is used to select PWM phas- ...
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Constant-Current LED Drivers and I/O Expanders with PWM Intensity Control Table 6. Output Registers Format REGISTER PORT P0 LEVEL OR PWM Port P0 is static-low logic-level logic port with logic input buffer enabled; reading this port returns 0. Still ...
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Constant-Current LED Drivers and I/O Expanders with PWM Intensity Control Table 6. Output Registers Format (continued) REGISTER Port P1 level or PWM Port P2 level or PWM Port P3 level or PWM Port P4 level or PWM Port P5 ...
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Constant-Current LED Drivers and I/O Expanders with PWM Intensity Control Output Current Registers Each output port’s individual constant-current sink can be set to be either half or full global current. The indi- vidual currents are set by the output ...
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... By default, maximum current is 20mA, so the default half current is 10mA. Ramp-Up and Ramp-Down Controls The MAX6966/MAX6967 provide automatic controls that allow the currents’ outputs to be ramped down into automatic shutdown (ramp-down), and ramped up again out of shutdown (ramp-up) without further inter- action (Figures 4 and 5) ...
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... MAX6966/MAX6967 are in hold-off, fade-off, or ramp- up condition (Table 4). The configuration register also enables or disables ramp-up. One write to the configura- tion register can put the MAX6966/MAX6967 into shut- down (using hold-off and fade-off settings in the fade Table 9. Ramp-Down Register Format REGISTER ...
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Constant-Current LED Drivers and I/O Expanders with PWM Intensity Control Table 10. Ramp-Up Register Format REGISTER Write ramp-up Read ramp-up Ramp-up time (f = 32768Hz) PWM Instant full current coming out from shutdown 1/16s ramp-up to full current coming ...
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... The first byte, D15 through D8, is the com- mand, and the second byte, D7 through D0, is the data byte (Table 11). Connecting Multiple MAX6966/MAX6967s Multiple MAX6966/MAX6967s can be interfaced to a common SPI bus by connecting DIN inputs together, connecting SCLK inputs together, and providing an individual CS per MAX6966/MAX6967 device (Figure 8) ...
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... DOUT of one device to the DIN of the next, and driving SCLK and CS lines in paral- lel (Figure 9). This connection allows the MAX6966/ MAX6967s to be read. Data at DIN propagates through the internal shift registers and appears at DOUT 15.5 clock cycles later, clocked out on the falling edge of SCLK ...
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... N- DOUT N-31 N-30 N-29 Figure 12. Transmission of More than 16 Bits to the MAX6966/MAX6967 ______________________________________________________________________________________ Any register data within the MAX6966/MAX6967 can 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, D15 first to D0 last. ...
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... Differences Between the MAX6966 and The MAX6966 powers up with DOUT/OSC configured as DOUT output by default. The MAX6967 powers up with DOUT/OSC configured as OSC input by default. Both parts allow the DOUT/OSC pin function to be changed through the configuration register (Table 4). If ...
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... An I/O port can be used to automatically generate a shutdown/run output from the MAX6966/MAX6967. The shutdown/run output is active low when the MAX6966/MAX6967 are in run mode, hold-off, fade-off, or ramp-up, and go high automatically when the MAX6966/MAX6967 finally enter shutdown after fade- off. Program the port’s output register to value 0x00, which puts the output into static constant-current mode (Table 6). Program the port’ ...
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... Driving Load Currents Higher than 20mA The MAX6966/MAX6967 can be used to drive loads needing more than 20mA, like high-current white LEDs, by paralleling outputs. For example, consider a white LED that needs to be driven with 70mA. This LED can µ ...
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Constant-Current LED Drivers and I/O Expanders with PWM Intensity Control CURRENT REFERENCE INTERNAL OSCILLATOR EXTERNAL CLOCK INPUT OSC CONFIGURATION CLK CS DIN DOUT ______________________________________________________________________________________ RAMP-UP/RAMP-DOWN CONTROLS PWM CONTROLLER REGISTER I/O REGISTER 4-WIRE SERIAL INTERFACE TRANSISTOR COUNT: 14,865 PROCESS: BiCMOS ...
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Constant-Current LED Drivers and I/O Expanders with PWM Intensity Control (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.) 28 ______________________________________________________________________________________ Package Information PACKAGE OUTLINE, ...
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Constant-Current LED Drivers and I/O Expanders with PWM Intensity Control (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 0.10 C PKG 12L ...