STEVAL-ILL029V2 STMicroelectronics, STEVAL-ILL029V2 Datasheet

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I²C interfaced, advanced LED controller/driver with keyscan, standby power management and real time clock (RTC) Features ■ LED controller driver with 13 outputs (8 segments/5 digits) ■ Standby power management to host ■ Integrated low-power, accurate RTC ■ Integrated remote ...

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Contents Contents 1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

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STLED325 3.16 GPIO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

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Contents 10.2 ISET variation with RSET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

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STLED325 List of tables Table 1. Device summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

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List of figures List of figures Figure 1. Functional block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

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STLED325 1 Description The STLED325 is a compact LED controller/driver that interfaces microprocessors to LED displays through serial I figuration. The STLED325 drives discrete LEDs in 8 segment/5 digit configuration while functioning from a supply voltage of ...

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Functional and application diagram 2 Functional and application diagram Figure 1. Functional block diagram ISET Current source Vcc Voltage regulator SCL SDA WAKE_UP GPIO1 GPIO2 VREG MUTE KEY1-KEY2 XIN XOUT 8/62 POR & Output Soft-start segments Bandgap Internal and UVLO ...

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STLED325 Figure 2. Application diagram Microcontroller or CPU External 32.768KHz crystal From remote control sensor STLED325 SCL SDA LED 4-digit 7-segment (+dot-point) display panel READY 4 STBY DIG1-DIG4 IRQ_N 8 SEG1/KS1- MUTE SEG8/KS8 WAKE_UP XIN DIG5 XOUT VBAT IR_IN GPIO1 ...

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Functional and application diagram Figure 3. Pin configurations 10/62 MUTE 1 IRQ_N 2 GPIO1 3 GPIO2 4 STLED325 IR_IN 5 SDA 6 SCL 7 WAKE_UP 8 Doc ID 17576 Rev 1 STLED325 24 SEG1/KS1 23 SEG2/KS2 22 SEG3/KS3 21 SEG4/KS4 ...

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STLED325 3 Functional description The STLED325 is a common anode LED driver controller which can be used to drive red, green or blue LEDs as the current is adjustable through the external resistor. In the common anode configuration, the digit ...

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Functional description 3.4 Display types Figure 4. Display types 3.5 Keyscan The full keyscan is illustrated in the later section of the datasheet. One diode is required per key switch. The keyscan circuit detects any combination of keys being pressed ...

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STLED325 3.6.2 Watchdog timer Another watchdog timer is present in the Watchdog timer register at address 09h of the RTC register map. This watchdog timer can be used to program timer values of greater than 15s. Bits BMB4-BMB0 store a ...

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Functional description 3.8 LED drivers The constant current capability per output segment and is set for all the outputs using a single external resistor. When acting as digit drivers, the outputs source current to the ...

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STLED325 3.10.1 Cold boot up When power is first applied to the system, the STLED325 is reset. It will then manage the power to the main board by bringing the STBY pin to a low level. This wakes up the ...

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Functional description Figure 5. Power-up condition VCC to STLED325I Internal POR VCC to STLED325I Internal POR STBY READY MUTE Note: 1 Guard timer is turned off by default upon READY assertion Guard timer kept on ...

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STLED325 3.10.2 Entering standby mode The STLED325 controls the power to the main board using the STBY pin. During normal operation, the STBY pin is a low level which externally controls a Power MOS switch to enable power to the ...

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Functional description 3.10.3 Wake-up The STLED325 can wake-up from any one of the following sources: – Front-panel keys – Remote-control keys – Real time clock (RTC conditions (alarm, watchdog timer, oscillator fail) – External wake-up pin (by a ...

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STLED325 3.11 Real time clock (RTC) The STLED325 integrates a low power Serial RTC with a built-in 32.768 kHz oscillator (external crystal controlled). Eight bytes of the SRAM are used for the clock/calendar function and are configured in binary coded ...

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Functional description 3.11.2 Writing to the real time clock The time and date may be set by writing to the RTC registers. The new RTC time can be updated by writing to the RTC registers. The new time only takes ...

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STLED325 WDFEn = watchdog flag enable 12/ hour or 24 hour format (‘0’ for 24-hour format and ‘1’ for 12-hour format). For 12 hour PM display, the 8th segment of last digit (digit 4) is driven to indicate ...

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Functional description Table 3. Alarm repeat modes RPT5 RPT4 the RPT value is other than the valid ones listed in the table, the default repeat ...

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STLED325 3.11.6 Initial power-on defaults Upon application of power to the device, the register bits in the RTC initially power-on in the state indicated in table below. Table 5. Initial power-on defaults OSC_ST 0 Initial power-on defaults value of the ...

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Functional description 3.11.7 Programmable display The default display of the RTC time is the 2 MSB digit for hour and the 2 LSB digit for minutes. However, if the MD_HM_MS bit is set, then the RTC display for the digits ...

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STLED325 Table 7. LUT with ppm against the calibration register values (continued) Sign bit ...

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Functional description 3.12 Remote control decoder The remote control (RC) decoder module decodes the signal coming from IR_IN pin. The IR remote control protocols recognized by STLED325 are Philips-RC-5, RCMM, Thomson RCA, R2000, NEC and R-STEP protocols. The selection of ...

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STLED325 While the interrupt is being read by the MCU and a new GPIO or key data comes in, no new interrupt is generated but the register for GPIO and KEY data is updated so that the MCU does not ...

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Functional description Figure 10. Power sense circuit For the STLED325 itself, there is the normal operational mode where the supply is from the When the V CC from the V to the battery or super-cap supply. ...

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STLED325 Figure 11. Circuit The minimum operating voltage of STLED325 is 2.5 V with a typical VBAT voltage of VCC- VF (diode). Therefore, the typical delta voltage swing across the capacitor is Δ – V – ...

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Functional description spike is very low into the battery. The battery must be protected against such spikes. This is not relevant for super-cap. During the switching from V 3.17.2 Battery low warning The STLED325 automatically performs battery voltage monitoring upon ...

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... In this case the transmitter must leave the data line High to enable the master to generate the STOP condition. 2 Note: Refer to Philips I C specification or contact STMicroelectronics for more information on I Doc ID 17576 Rev 1 Functional description 2 C. 31/62 ...

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Functional description Table 9. Pin description Pin number WAKE_UP DIG4 –DIG1 14 15, 16 KEY2-KEY1 SEG8/KS8 SEG1/KS1 ...

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STLED325 4 Electrical ratings 4.1 Absolute maximum ratings (T Absolute maximum ratings are those values above which damage to the device may occur. Functional operation under these conditions is not implied. Exposure to absolute maximum rating conditions for extended periods ...

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Electrical ratings 4.2 Recommended operating conditions 4.2.1 DC electrical characteristics (T = -40 to +85 ° Table 12. DC electrical characteristics Symbol V External supply voltage CC Internal logic supply voltage and V REG regulator output HIGH level ...

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STLED325 4.3 Power consumption estimation Each port of the STLED325 can sink a maximum current into an LED with a 3.4 V forward voltage drop when operated from a supply voltage of 5.0 V. The minimum voltage ...

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Electrical ratings Table 15. Power supply characteristics (T Symbol Operating power supply Quiescent supply current CC(Q) ) Table 16. Dynamic switching characteristics (T GND=0.0V, Typical values are at 25°C) Symbol f SCL clock frequency SCL t Clock ...

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STLED325 Table 17. Timing characteristics typical values are at 25 °C Parameter Propagation delay time Rise time Fall time Input capacitance Mute active to standby active GPIO edge to interrupt trigger (T = -40 to +85 ° ...

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Electrical ratings 4.4 Oscillator and crystal characteristics Table 18. Oscillator characteristics Symbol V Oscillator start voltage STA tSTA Oscillator start time CL1 X IN CL2 X OUT IC-to-IC frequency variation 1. Reference value. T Table 19. Crystal electrical characteristics Symbol ...

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... Battery range and battery detect Symbol (1) VBAT Battery supply voltage I Battery supply current BAT 1. STMicroelectronics recommends the RAYOVAC BR1225 or BR1632 (or equivalent) as the battery supply. 2. For rechargeable back-up, V Figure 13. Power down/up mode ac waveforms Table 22. Power down/up AC characteristics Symbol tpD SCL and SDA at V trec 1 ...

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Electrical ratings 1. All voltages are referenced to GND. 2. Valid for ambient operating temperature: T Table 24. Thermal shutdown characteristics Symbol Thermal shutdown TSD threshold THYS Hysteresis 1. Thermal shutdown is not production tested. Figure 14 40/62 ...

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STLED325 5 Display RAM address and display mode The display RAM stores the data transmitted from an external device to the STLED325 through the serial interface. The addresses are as follows, in 8-bits unit: Table 25. Bit map for segment ...

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KEY matrix and key-input data storage RAM 6 KEY matrix and key-input data storage RAM The key matrix is of 8x2 configuration, as shown below: Figure 15. KEY matrix and key-input data storage RAM The data of each key are ...

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STLED325 7 Commands A command sets the display mode and status of the LED driver. The first 1 byte input to the STLED325 through the SDA pin after the slave address is regarded as a command. If slave address is ...

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Commands 001: Philips RC-6 (optional only enabled for Philips) 010: Philips RC-5 011: Philips RCMM 100: NEC 101: R-STEP 110: Thomson R2000 111: Thomson RCA When b7=‘0’, incoming RC data is output on SDA in decoded format where the Device ...

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STLED325 enables the GPIO0 as input enables the GPIO0 as output b4: configuration for the GPIO1 enables the GPIO1 as input enables the GPIO1 as output b5 = ...

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Commands 7.2 Data setting command This command sets the data-write and data-read modes. MSB 0 1 Description: Bits b7- decoded as a data setting command. The subsequent bits are decoded as follows 00: data ...

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STLED325 Table 27. Data Write 2 command. B5 b4: 01 B1- Any subsequent data bytes in this case will be ignored. Table 28. Data Read 1 command. b5 b4: 10 b1- Table ...

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Commands In fixed address mode, the address command has to be sent followed by the display data. When next byte of data written, address command has to be sent again before new display data byte. When the ...

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STLED325 incremented. Upon reaching the last display memory address, the address jumps to 0x10 represents the first address location of the display memory. In fixed address mode, the address command has to be sent followed by the display ...

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Commands Figure 18. Interrupt bit mapping in Byte 2 Byte 2: MSB b7-b4 = Normal operation In the normal mode of operation, when any key is pressed or when alarm/watchdog is triggered, the STLED325 sets the flags ...

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STLED325 7.5 Display control and hotkey setting command 1 0 Bits b7- decoded as a display control and hotkey setting command. The subsequent bits are decoded as follows sets display control for dimming setting ...

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Commands 0: Display off (keyscan continues) 1: Display on When the decoding is based on bits b1-b0 as illustrated below 01: IR hot-key configuration of ADR and DATA. After this 3 bytes are sent ...

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STLED325 7.6 Keyscanning and display timing Figure 20. Keyscanning and display timing Grid DIG1 Outputs tDISP=500us SEG1 t=1/16 of SEG2 tDISP SEG3 SEGn The value is fixed by the internal clock from the oscillator. One cycle of keyscanning consists of ...

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State 8 State 8.1 Default state upon power-up Table below shows the default state of the STLED325 upon power-up. Table 30. Power-up defaults Serial number 8.2 Initial state On power application, ...

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... STLED325 9 Remote control protocols Contact STMicroelectronics for more information on RC protocols or refer to separate document (TBD). Doc ID 17576 Rev 1 Remote control protocols 55/62 ...

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Application information 10 Application information 10.1 Power supply sequencing Proper power-supply sequencing is advised for all CMOS devices recommended to always apply V CC 10.2 I variation with R SET The graph of I SET Figure 21. Rext ...

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STLED325 10.3 Application diagram Figure 22. Application schematic ain rem ote control sensor C rystal (32.768K Resistors: RSET = external ...

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Package mechanical data 11 Package mechanical data In order to meet environmental requirements, ST offers these devices in different grades of ® ECOPACK packages, depending on their level of environmental compliance. ECOPACK specifications, grade definitions and product status are available ...

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STLED325 Figure 23. QFN32 package dimensions Doc ID 17576 Rev 1 Package mechanical data 59/62 ...

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Package mechanical data Figure 24. QFN32 carrier tape 60/62 Doc ID 17576 Rev 1 STLED325 ...

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STLED325 12 Revision history Table 32. Document revision history Date 27-Apr-2011 Revision 1 Initial release. Doc ID 17576 Rev 1 Revision history Changes 61/62 ...

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