stled325 STMicroelectronics, stled325 Datasheet
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stled325 Summary of contents
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... Table 1. Device summary Order code STLED325QTR April 2011 Description The STLED325 is a compact LED controller/ driver that interfaces microprocessors to LED displays through serial I LEDs connected in common anode configuration and includes keyscanning for key matrix which automatically scans and de-bounces a matrix switches ...
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... Entering standby mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Wake- Reading the real time clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Writing to the real time clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Register table for RTC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Setting alarm clock registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Century bits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Initial power-on defaults . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Programmable display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Lookup table with ppm against the calibration register values . . . . . . . . 24 Doc ID 17576 Rev 1 STLED325 ...
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... STLED325 3.16 GPIO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 3.17 Power sense circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 3.17.1 3.17.2 3.17.3 3.18 Bus characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 4 Electrical ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 4.1 Absolute maximum ratings ( °C, GND = 4.2 Recommended operating conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 4.2.1 4.3 Power consumption estimation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 4.4 Oscillator and crystal characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 4.5 ESD performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 5 Display RAM address and display mode . . . . . . . . . . . . . . . . . . . . . . . 41 6 KEY matrix and key-input data storage RAM . . . . . . . . . . . . . . . . . . . . 42 7 Commands ...
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... Contents 10.2 ISET variation with RSET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 10.3 Application diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 11 Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 12 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61 4/62 Doc ID 17576 Rev 1 STLED325 ...
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... STLED325 List of tables Table 1. Device summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Table 2. Register table for RTC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Table 3. Alarm repeat modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Table 4. Century bits examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Table 5. Initial power-on defaults . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Table 6. RTC display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Table 7. LUT with ppm against the calibration register values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Table 8. Different power operation modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Table 9. ...
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... Data write command (b7 b6) for GPIO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46 Figure 17. Interrupt bit mapping in Byte Figure 18. Interrupt bit mapping in Byte Figure 19. Blanking time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 Figure 20. Keyscanning and display timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 Figure 21. Rext versus Iseg curve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 Figure 22. Application schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 Figure 23. QFN32 package dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59 Figure 24. QFN32 carrier tape . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60 6/62 Doc ID 17576 Rev 1 STLED325 ...
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... 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 The maximum segment current for the display digits is set through a single external resistor. Individual digits may be addressed and updated without rewriting the entire display ...
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... Dimming Dimming Freq) KeyData Mem KeyData Mem ( RTC + IR_IN RC 32KHz decoder Osc VBAT Doc ID 17576 Rev 1 STLED325 Thermal Remote Ctrl Internal protection Decoder & reset Guard VCC timer Detect Vbat Detect SEG1/KS1 8 8-bit 20- bit output Output ...
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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 GPIO2 ISET VREG KEY1-KEY2 R 2 Key scan ...
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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 20 SEG5/KS5 19 SEG6/KS6 18 SEG7/KS7 17 SEG8/KS8 ...
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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 outputs source the current to the anodes while the segment outputs sink the current from the cathodes ...
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... The keyscan circuit detects any combination of keys being pressed during each de-bounce cycle. The keyscan matrix on the STLED325 passes command from the front panel to the host processor through the SDA pin on STLED325. The STLED325 can be programmed to wake-up the system from standby using any of the 16 keys pressed on the front panel. ...
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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 binary multiplier and the three bits RB2-RB0 select the resolution where: 000 = 1/16 second (16 Hz) ...
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... STLED325 supports multiple remote control protocols decoding by setting the appropriate register. The STLED325 is able to cut-off the power to the main board for standby operation for good power management. STBY will be set to high when READY signal goes from high to low, I command for standby is seen or when the guard timer has finished counting down to 0, whichever occurs first ...
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... If the microprocessor does not assert the READY pin to a high within 10s (default), the STLED325 cuts off the power to the Host by asserting the STBY pin. The high level on READY pin signifies that the processor is ready. After this, the processor can configure the STLED325 by sending the various I RTC display mapping, hot-keys ...
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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 during READY high condition, the guard timer registers must be set accordingly by proper commands through this power-up condition, Guard timer is triggered by internal POR pulse ...
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... 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 main board. The STLED325 asserts the STBY pin to a high when any one of the following conditions occur: – ...
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... The timer value is the programmed value by the user (1-15s). If the user did not change the value before entering standby, then it remains 10s. – Also note that the guard timer is off when the STLED325 is in the standby mode. The guard timer is thus triggered by a de-assertion of the STBY signal or by internal power on reset signal ...
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... Corrections for 28, 29 (leap year - valid until year 2100), 30 and 31 day months are made automatically. The RTC operates as a slave device through the slave address of the STLED325 on the serial bus. Access is obtained by implementing a start condition followed by the correct device slave address. The 16 bytes contained in the device can then be accessed sequentially in the following order: – ...
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... BMB1 BMB0 AI 10M Alarm month Alarm date AIarm hour Alarm minutes Alarm seconds Rsvd (bypass mode) Doc ID 17576 Rev Functional/range BCD format Seconds Minutes Hours Day Date Century/month Year Calibration RB1 RB0 Watchdog Al month Al date AI hour Al min Al sec Flags STLED325 00-59 00-59 00-23 01-7 01-31 0-3/01-12 00-99 01-12 01-31 00-23 00-59 00-59 ...
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... It can also be programmed to go off while the STLED325 is in the standby mode to serve as a system wake-up call. Bits RPT6-RPT1 put the alarm in the repeat mode of operation. Codes not listed in the table default to the once per second mode to quickly alert the user of an incorrect alarm setting ...
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... CB[1] Leap year Doc ID 17576 Rev 1 STLED325 RPT6 Repeat alarm mode 1 Once per week 0 Once per second 0 Once per minute 0 Once per hour 0 Once per day 0 Once per month 0 Once per year (1) Example Yes ...
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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 RTC registers. Note: All other control bits power- default state of 0 unless otherwise specified. ...
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... STLED325 Table 7 PPM ...
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... STLED325 Table 7. LUT with ppm against the calibration register values (continued) Sign bit Counts/bit ...
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... Interrupt The STLED325 interrupts the Host by pulling the IRQ_N pin to a low-level both in normal mode of operation and during wake-up. The interrupt is enabled by STLED325 when any of the conditions occur: – Front panel key press in normal operation or during system standby state – ...
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... The STLED325 supports cutting-off power to the main board for standby operation for good power management. STBY will be set to high when the READY transitions from high to low. During a cold boot up or wake up from standby, if the READY pin stays low, the STLED325 will assert the STBY when the guard timer has finished counting down to 0. ...
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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 conserve power and maintain long battery life in this battery supply mode, only the RTC and the clock to the RTC remain operational ...
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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 – where V is approximately 0.5 V. Therefore, F Δ – 0.5 – 2 Since the typical battery current (IBAT) is limited to 7 µA, the capacitance and duration of power-out time can be calculated using the formula CΔ ...
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... During the switching from V 3.17.2 Battery low warning The STLED325 automatically performs battery voltage monitoring upon power-up. If the interrupt for this condition (ABE) is enabled, the RTC will generate an interrupt pulse if the battery voltage is found to be less than a minimum of 2.5V. However, this condition is unlikely to go away very quickly as time is needed for the battery to be replaced, and it is not desirable to keep issuing an interrupt ...
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... STLED325 3.18 Bus characteristics The bus is intended for communication between different ICs. It consists of two lines: a bi- directional data signal (SDA) and a clock signal (SCL). Both the SDA and SCL lines must be connected to a positive supply voltage (typical voltage is 3.3 V) via a pull-up resistor (typical value ...
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... EPAD 32/62 Symbol Type Output from the STLED325 to gracefully mute the audio MUTE OUT before entering standby mode Interrupt output (active low level type) to interrupt the IRQ_N OUT MCU under various conditions GPIO0 IN/OUT GPIO0 that can be configured as an input or output ...
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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 may affect device reliability. All voltages are referenced to GND ...
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... High level guaranteed Low level guaranteed High level guaranteed Low level guaranteed OL2 Drivers off V LED V DIGIT V DIGIT LED current = SEG Doc ID 17576 Rev 1 STLED325 Min Typ Max 4.5 5.0 5.5 1.62 1.8 1.98 1.35 1.98 0 0. 0.4 -150 = -30 ...
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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 drop across the internal LED drivers is thus 5.0 - 3.4 = 1.6 V. The STLED325 can sink 320 mA when all outputs are operating as LED segment drivers at full current ...
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... Display OFF V CC Parameter Doc ID 17576 Rev 1 = -40 to 85°C) Min Typ = 5.5V = 5.5V = -40 to +85 ° 5.0V ± 10 Min Typ Max 0 400 1.3 600 300 300 600 600 100 0 600 1 STLED325 Max Unit TBD Units kHz µ µs ns µs ms ...
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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 ° Symbol Min Typ Max t 300 PLZ t 100 PZL t 2 TZH1 t 0 ...
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... Guaranteed by design. 38/62 Parameter Conditions ≤ 10 seconds deg 3.0 V, CFM-145 ( Parameter Conditions Resonant (1) frequency (2) Doc ID 17576 Rev 1 Min Typ Max 1 -20 + pF, 32.768 KHz) manufactured by Citizen. L Min Typ Max 32.768 ( 12.5 STLED325 Unit Ppm Unit KHz kΩ pF ...
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... STLED325 4.5 ESD performance Table 20. ESD performance Symbol MIL STD 883 method 3015 ESD Table 21. 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 ...
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... Thermal shutdown characteristics Symbol Thermal shutdown TSD threshold THYS Hysteresis 1. Thermal shutdown is not production tested. Figure 14 40/62 =- Parameter Conditions VCC=5V VCC=5V characteristics Doc ID 17576 Rev 1 = 2.5V to 5.5V (except where noted) CC (1) Min Typ Max 140 15 STLED325 Unit Deg C Deg C ...
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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 1 to segment 8 Seg1 ...
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... SEG/KS pins can see a maximum load of 300pF. This load condition is important for the key dis-charge cycle time. 42/62 Key 1 Key 2 Key 1 Seg2 KS2 Seg3 Seg6 KS6 Seg7 Doc ID 17576 Rev 1 STLED325 Key 2 Key 1 Key 2 KS3 Seg4 KS4 KS7 Seg8 KS8 ...
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... 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 not transmitted before the commands/data are transmitted, the commands/data being transmitted are invalid (however, the commands/data already transmitted remain valid) ...
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... GPIO0 44/ Doc ID 17576 Rev 1 STLED325 LSB ...
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... Display mode setting: the 4-digit, 8-segment mode is selected (default: display off and keyscan on). Remote control protocol setting: RC-5. Guard timer setting: turned on with 10s. After the first command is processed by STLED325, the guard timer is turned off until it is turned on by the host. Guard timer action: Issue Standby. ...
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... Write memory (display). Address range: 0x10-0x13. Start ad-dress pointer location is 0x10. Write memory (discrete LED). Address: 0x14. Write data into GPIOs if they are configured as outputs (see note 1) LSB RSVD RSVD MSB6 RSVD GPIO0 Doc ID 17576 Rev 1 STLED325 LSB RSVD RSVD RSVD ...
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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 29. Data Read 2 command. b5 b4: 11 b1- power application, the normal operation mode and address increment mode is set with the default display memory address set to 0x10 (start of display memory address location) ...
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... GPIOs output) output) Byte For display enable Byte 4 Front Panel Hot Key Bank 1 Byte 5 Front Panel Hot Key Bank 2 Doc ID 17576 Rev 1 STLED325 LSB (b0 Guard timer setting Digit 5 discrete 7-segment LED display LED config configuration setting B2 ...
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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 data. When next byte of data written, address command has to be sent again before new display data byte ...
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... Normal operation In the normal mode of operation, when any key is pressed or when alarm/watchdog is triggered, the STLED325 sets the flags in the above interrupt flag register and asserts the IRQ_N pin. The data which caused the interrupt to assert remains in the buffer until it is changed by another key-press the micro processor to issue the read interrupt command to ascertain what caused the interrupt ...
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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 as shown in the table below. Display control and dimming setting when ...
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... Front panel hot keys can be configured by sending 2 bytes of key data to configure any key as hot-key from any of the 2 banks. Any number of keys can be configured as hot-keys. When input key code matches any one of the predefined key codes stored in the internal RAM, the STLED325 de-asserts the STBY output. 52/62 Doc ID 17576 Rev 1 ...
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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 one frame, and data of 8x2 matrices are stored in the RAM ...
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... If the user wishes to display the RTC value during standby, then the user must configure the STLED325 by sending the appropriate command. If the user does not configure the STLED325 to display the RTC in standby, the LED shows the same value as was written previously in the LED display memory location. ...
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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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... 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 versus Iseg curve 56/62 before applying any signals to the input/output or control pins. SET variation with R is shown in SET Doc ID 17576 Rev 1 Figure 21. STLED325 ...
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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 resistor for current setting R1 = 1-10 KO SDA external pull-up resistor R2 = 1-10 KO SCL external pull-up resistor R3 = 1-10 KO IRQ_N external pull-up resistor ...
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... ECOPACK specifications, grade definitions and product status are available at: www.st.com. ECOPACK trademark. Table 31. QFN32 ( mm) mechanical data Symbol ddd 58/62 Millimeters Min Typ 0.80 0.90 0 0.02 0.20 0.18 0.25 4.85 5.00 3.35 3.45 4.85 5.00 3.35 3.45 0.50 0.30 0.40 Doc ID 17576 Rev 1 STLED325 ® Max 1.00 0.05 0.30 5.15 3.55 5.15 3.55 0.50 0.08 ...
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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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... Australia - Belgium - Brazil - Canada - China - Czech Republic - Finland - France - Germany - Hong Kong - India - Israel - Italy - Japan - Malaysia - Malta - Morocco - Philippines - Singapore - Spain - Sweden - Switzerland - United Kingdom - United States of America 62/62 Please Read Carefully: © 2011 STMicroelectronics - All rights reserved STMicroelectronics group of companies www.st.com Doc ID 17576 Rev 1 STLED325 ...