STP24DP05 24-bit constant current LED sink driver with output error detection Features ■ Low voltage power supply down to 3 V ■ 8 x 3 constant current output channels ■ Adjustable output current through external resistors ■ Short and open output error detection ■ Serial data IN/Parallel data OUT ■ Shift register data flow registers control ■ Accepts 3.3 V and 5 V micro driver ■ Output current: 5-80 mA ■ 25 MHz clock frequency ■ High thermal efficiency package Description The STP24DP05 is a monolithic, low voltage, low current power 24-bit shift register designed for LED panel displays. The device contains a 8 x 3-bit serial-in, parallel-out shift register that feeds a 8 x 3-bit D-type storage register. In the output stage, twenty-four regulated current sources were designed to provide 5-80 mA constant current to drive the LEDs. The 8x3 shift registers data flow sequence order can be managed with two dedicated pins. TQFP48 The data detection results are loaded in the shift registers and shifted out via the serial line output. The detection functionality is activated with a dedicated pin or as alternative, through a logic sequence that allows the user to enter or exit from detection mode. Through three external resistors, users can adjust the output current for each 8-channel group, controlling in this way the light intensity of LEDs. The STP24DP05 guarantees a 20 V output driving capability, allowing users to connect more LEDs in series. The high clock frequency, 25 MHz, makes the device suitable for high data rate transmission. The 3.3 V of voltage supply is useful for applications that interface any micro from 3.3 V. The STP24DP05 has a dedicated pin to activate the outputs with a sequential delay, that will prevent inrush current during outputs turn-ON. The device detection circuit checks 3 different conditions that can occur on the output line: short to GND, short to VO or open line. Table 1. May 2008 Device summary Order code Package Packaging STP24DP05BTR TQFP48 Tape and reel Rev 1 1/26 www.st.com 26 Contents STP24DP05 Contents 1 Summary description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.1 2 Pin connection and description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Electrical ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2.1 Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2.2 Thermal data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2.3 Recommended operating conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 3 Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 4 Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 5 Equivalent circuit and outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 6 Timing diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 7 Feature description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 7.1 DG: gradual outputs delay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 7.2 Error detection condition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 7.3 Phase one: “entering in detection mode” . . . . . . . . . . . . . . . . . . . . . . . . . 16 7.4 Phase two: “error detection” . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 7.5 Phase three: “resuming to normal mode” . . . . . . . . . . . . . . . . . . . . . . . . . 18 7.6 Shift registers data flow control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 7.7 EFLAG/TFLAG - output detection and overtemperature monitoring . . . . 19 8 Typical application schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 9 Typical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 10 Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 11 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 2/26 STP24DP05 1 Summary description Summary description Table 2. Current accuracy Typical current accuracy Output voltage Output current Between bits 1.1 VDD Temperature 3.3 V to 5 V 25 °C Between ICs ≥ 1.0 V ±3% ±6% ≥ 15 to 80 mA ≥ 0.2 V ±6% ±6% 5 to 15 mA Pin connection and description Figure 1. Pin connection TQFP48 exposed pad 3/26 Summary description Table 3. 4/26 STP24DP05 Pin description Pin N° Symbol Name and function 1, 7, 12, 25, 30, 36 GND Ground terminal 2 SDI Serial data input 35 SDO Serial data output 4 CLK Clock for serial data 3 LE\DM 5 DM 13, 16, 19, 22, 39, 42, 45, 48 R1 - 8 8 TF Thermal flag (open drain) 29 EF Error detection flag (open drain) 9 DG Gradual delay 15, 17, 20, 23, 37, 40, 43, 46 B1 - 8 8 channel LED driver outputs 32 OE-B Output enable for B1 - 8 33 OE-G Output enable for G1 - 8 34 OE-R\DM Output enable for R1 - 8 28 REXTR Control outputs R1 - 8 27 REXTG Control outputs G1 - 8 26 REXTB Control outputs B1 - 8 14, 18, 21, 24, 38, 41, 44, 48 G1 - 8 8 channel LED driver outputs 10 DF0 Data banks flow bit 0 11 DF1 Data banks flow bit 1 31 VDD Supply voltage terminal Data latch in both SH register Detection mode pin 8 channel LED driver outputs STP24DP05 Electrical ratings 2 Electrical ratings 2.1 Absolute maximum ratings Stressing the device above the rating listed in the “absolute maximum ratings” table may cause permanent damage to the device. These are stress ratings only and operation of the device at these or any other conditions above those indicated in the operating sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Refer also to the STMicroelectronics SURE program and other relevant quality documents. Table 4. Absolute maximum ratings Symbol 2.2 Parameter Value Unit 0 to 7 V VDD Supply voltage - digital VO Output voltage - LED driver -0.5 to 20 V VTF and VER Open drain absolute voltage 0 to 7 V IO Output current - LED driver 80 mA VI Input voltage - digital -0.4 to VDD+0.4 V IGND GND terminal current 2000 mA fCLK Clock frequency 30 MHz Value Unit Thermal data Table 5. Symbol Thermal data Parameter TOPR Operating temperature range -40 to 125 °C TSTG Storage temperature range -40 to 150 °C RthJC Thermal resistance junction-case 25 °C/W 5/26 Electrical ratings 2.3 STP24DP05 Recommended operating conditions Table 6. Symbol Recommended operating conditions Parameter Test conditions Min Typ 3.0 Max Unit 5.5 V 20 V 80 mA VDD Supply voltage VO Output voltage IO Output current OUTn IOH Output current SERIAL-OUT +10 mA IOL Output current SERIAL-OUT -10 mA VIH Input voltage 0.7VDD VDD+0.3 V VIL Input voltage -0.3 0.3VDD V 5 twLAT LE pulse width 15 ns twCLK CLK pulse width 15 ns twEN OE pulse width 150 ns 15 ns 5 ns 10 ns tSETUP(D) Setup time for DATA VDD = 3.0 V to 5.0 V tHOLD(D) Hold time for DATA tSETUP(L) Setup time for LATCH fCLK Clock frequency Cascade operation (1) 25 MHz 1. If the device is connected in cascade, it may not be possible achieve the maximum data transfer. Please consider the timings carefully. 6/26 STP24DP05 Electrical characteristics 3 Electrical characteristics Table 7. Electrical characteristics (VDD = 3.3 V to 5 V, T = 25 °C, unless otherwise specified.) Symbol Parameter Test conditions Min Typ Max Unit VIH Input voltage high level 0.7VDD VDD V VIL Input voltage low level GND 0.3VDD V IOH Output leakage current VOH = 20 V 10 µA VOL Output voltage (Serial-OUT) IOL = 1 mA 0.4 V VOH Output voltage (Serial-OUT) IOH = -1 mA VDD-0.4V V VO = 0.3 V, REXT = 2 kΩ, IO = 10 mA 20 mA VO = 0.3 V, REXT = 1 kΩ, IO = 20 mA 80 mA IOL3 VO = 0.3V, REXT = 250 Ω, IO = 80 mA 80 mA ∆IOL1 VO = 0.3 V, REXT = 2 kΩ, IO = 10 mA ±2 ±3 % ±2 ±3 % ±2 ±3 % IOL1 IOL2 ∆IOL2 ∆IOL3 RSIN(up) Output current Output current error among VO = 0.3 V, REXT = 1 kΩ, the channels IO = 20 mA (All outputs ON) VO = 0.3V, REXT = 250 Ω, IO = 80 mA Pull-up resistor 300 600 800 kΩ RSIN(down) Pull-down resistor 300 400 500 kΩ LE(up) DG(up) OE-R\ DM (up) OE-G (up) OE-B (up) DF0 DF1 Pull-up resistor 300 400 500 kΩ REXT = 1 kΩ OUT 0 to 15 = OFF 9 12 IDD(OFF2) REXT = 250 Ω OUT 0 to 15 = OFF 32 40 IDD(ON1) REXT = 1 kΩ OUT 0 to 15 = ON 13 18 REXT = 250 Ω OUT 0 to 15 = ON 35 40 IDD(OFF1) Supply current (OFF) mA Supply current (ON) IDD(ON2) 7/26 Electrical characteristics Table 7. Electrical characteristics (VDD = 3.3 V to 5 V, T = 25 °C, unless otherwise specified.) Symbol Parameter Thermal Thermal protection VTF Output voltage ITF Output current VEF Output voltage IEF Output current Table 8. STP24DP05 Test conditions Min Typ Max 170 °C 5 VTF @ 1 V V 20 mA 5 VEF @ 1 V V 20 mA Switching characteristics (VDD = 5 V, T = 25 °C, unless otherwise specified.) Symbol Parameter Typ Max tPLH1 Propagation delay time, CLK-OUTn, LE = H, OE = L VDD = 3.3 V 62 100 VDD = 5 V 38 60 tPLH2 Propagation delay time, LE-OUTn, OE = L VDD = 3.3 V 67 107 VDD = 5 V 44 60 tPLH3 Propagation delay time, OE-OUTn, LE = H VDD = 3.3 V 65 83 VDD = 5 V 38 45 Propagation delay time, CLK-SDO VDD = 3.3 V 14 22 36 tPLH VDD = 5 V 9 14 23 Propagation delay time, CLK-OUTn, LE = H, OE = L VDD = 3.3 V 46 70 tPHL1 VDD = 5 V 39 50 Propagation delay time, LE-OUTn, OE = L VDD = 3.3 V 51 76 tPHL2 VDD = 5 V 46 55 Propagation delay time, OE-OUTn, LE = H VDD = 3.3 V 41 45 tPHL3 VDD = 5 V 33 39 Propagation delay time, CLK-SDO VDD = 3.3 V 15 24 38 tPHL VDD = 5 V 9 15 24 Output rise time 10~90% of voltage waveform VDD = 3.3 V 33 57 tON VDD = 5 V 17 27 Output fall time 90~10% of voltage waveform VDD = 3.3 V 24 34 tOFF VDD = 5 V 25 37 Test conditions VDD = 3.3 V VIL = GND IO = 20 mA REXT = 1 kΩ VIH = VDD CL = 10 pF VL = 3.0 V RL = 60 Ω Min Unit ns ns ns ns ns ns ns ns ns ns tr CLK rise time (1) 5000 ns tf CLK fall time (1) 5000 ns 1. In order to achieve high cascade data transfer, please consider tr/tf timings carefully. 8/26 Unit STP24DP05 Block diagram 4 Block diagram Figure 2. Block diagram 9/26 Equivalent circuit and outputs 5 10/26 Equivalent circuit and outputs Figure 3. OExx terminal Figure 4. LE\DM terminal Figure 5. CLK, SDI terminal STP24DP05 STP24DP05 Equivalent circuit and outputs Figure 6. SDO terminal Figure 7. TF and EF 11/26 Timing diagrams 6 Timing diagrams Figure 8. Note: 12/26 STP24DP05 Timing diagram The latches circuit holds data when the LE terminal is low. 1 When LE\DML terminal is at high level, latch circuit hold the data it passes from the input to the output. 2 When either OE-R\DM, OE-G, OE-B terminals are at low level, output terminals R\G\B1 to R\G\B8 respond to the data, either ON or OFF. 3 When either OE-R\DM, OE-G, OE-B terminals are at high level, it switches off all the data on the output terminal R\G\B1 to R\G\B8. STP24DP05 Timing diagrams Figure 9. Clock, serial-in, serial-out 13/26 Timing diagrams Figure 10. Clock, serial-in, latch, enable, outputs Figure 11. Outputs 14/26 STP24DP05 STP24DP05 Feature description 7 Feature description 7.1 DG: gradual outputs delay This feature prevents large inrush current and reduces the bypass capacitors. The fixed delay time can be activated with DG = LOW and the typical output delay is 20 ns for each group of 8 outputs R, G, B. Eg: R1, G1, B1 has no delay, R2, G2, B2 has 20 ns delay and R3, G3, B3, has 40 ns delay, etc. Table 9. Typical gradual delay time table Delay time (ns) from ↓OExx R1 G1 B1 R2 G2 B2 R3 G3 B3 R4 G4 B4 R5 G5 B5 R6 G6 B6 R7 G7 B7 R8 G8 B8 DG = 0 0 30 60 90 120 150 180 200 0 0 0 0 0 0 0 DG = 1 7.2 Error detection condition Table 10. Detection conditions (VDD = 3.3 to 5 V, IO = 20 mA, tA = 25 °C) SW-1 Open Open line or output short or SW-3b to GND detected SW-2 Closed or SW-3a Note: Short on LED or short to V-LED detected => IODEC ≤ 0.4 x IO No error detected => IODEC ≥ 0.35 x IO => VO ≥ 2.6 V No error detected => VO ≤ 2.4 V IO = the output current programmed by the REXT IODEC = the detected output current in detection mode Table 11. Typical current threshold values to detect LED open line Iset (mA) Rext (Ω) Typ. out current detection (mA) 5 3920 1.28 10 1960 2.45 20 980 7.4 50 386 17 80 241 27 15/26 Feature description STP24DP05 Figure 12. Detection circuit 23 24 STP24DP05 16 7.3 Phase one: “entering in detection mode” From the “normal mode” condition the device can switch to the “error detection mode“ by a DM PIN set to LOW or a logic sequence on the OE-R/DM and LE/DM pins as showed in the following table and diagram: Figure 13. EDM timing diagram using DM pin Table 12. 16/26 SPI sequence to enter in detection mode - truth table CLK 1° 2° 3° 4° 5° OE-R/DM H L H H H LE/DM L L L H L STP24DP05 Feature description Figure 14. SPI sequence to enter in detection mode - time diagram OE-R/DM LE/DM After these five CLK cycles the device goes into the “error detection mode“ and at the 6th rise front of CLK the SDI data are ready for the sampling. 7.4 Phase two: “error detection” The eight data bits must be set “1“ in order to set ON all the outputs during the detection. The data are latched by LE/DM and after that the outputs are ready for the detection process. When the micro controller switches the OE-R/DM to LOW, the device drives the LEDs in order to analyze if an OPEN or SHORT condition has occurred. Figure 15. Detection diagram The LEDs status will be detected at least in 1 microsecond and after this time the microcontroller sets OE-R/DM in HIGH state and the output data detection result will go to the microprocessor via SDO. Detection mode and normal mode use both the same format data. As soon as all the detection data bits are available on the serial line, the device may go back to normal mode of operation. 17/26 Feature description 7.5 STP24DP05 Phase three: “resuming to normal mode” In order to re-enter in normal mode either the LE\DML pin or the sequence showed in the following table and diagram can be used: Table 13. SPI sequence to resume in normal mode - truth table CLK 1° 2° 3° 4° 5° OE-R/DM H L H H H LE/DM L L L L L Note: For proper device operation the "entering in detection" sequence must be followed by a "resume mode" sequence, it is not possible to insert consecutive equal sequence. 7.6 Shift registers data flow control The 8x3 shift registers have a default RGB sequence serial data flow as showed on block diagram Figure 2. The data can be redirected by DF0 and DF1 pins, these pins change the order of the data flow according to the following table: Table 14. 18/26 Shifter register data flow control Sequence DF0 DF1 BGR 1 1 BGR 0 1 RGB 1 0 GBR 0 0 STP24DP05 7.7 Feature description EFLAG/TFLAG - output detection and overtemperature monitoring The open-drain output EFLAG and TFLAG are used to report the STP24DP05 error flags. During normal operating conditions, the voltage on EFLAG/TFLAG is pulledup through an external resistor. When an error is detected, the internal switch is turned on, to GND. Figure 16. TF and EF test circuit 19/26 Typical application schematic 8 Typical application schematic Figure 17. Typical application schematic 20/26 STP24DP05 STP24DP05 Typical characteristics Figure 18. Typical external resistor values vs output current capabilities 4500 4000 External Resistance (Ohm) 9 Typical characteristics 3500 Temp. = 25°C Vdd = 5.0V Iset = 5mA; 10mA; 20mA; 50mA; 80mA 3000 2500 2000 1500 1000 500 0 0 10 20 30 40 50 60 70 80 90 Output Current (mA) Table 15. Typical external resistor values vs output current capabilities Iset 5 mA 10 mA 20 mA 50 mA 80 mA Rext (Ω) 4210 2050 1000 400 249 Figure 19. Typical dropout voltage vs output current Table 16. Typical dropout voltage vs output current Iset Rext (Ω) Avg (mV) @ 3.3 V Avg (mV) @ 5.0 V 5 4210 59 41 10 2050 130 90 20 1000 201 180 50 400 500 480 80 249 810 790 21/26 Package mechanical data 10 STP24DP05 Package mechanical data In order to meet environmental requirements, ST offers these devices in ECOPACK® packages. These packages have a lead-free second level interconnect. The category of second level interconnect is marked on the package and on the inner box label, in compliance with JEDEC Standard JESD97. The maximum ratings related to soldering conditions are also marked on the inner box label. ECOPACK is an ST trademark. ECOPACK specifications are available at: www.st.com 22/26 STP24DP05 Package mechanical data Figure 20. TQFP48 mechanical data TQFP48 MECHANICAL DATA mm. inch DIM. MIN. TYP A MAX. MIN. TYP. 1.6 0.15 0.063 A1 0.05 A2 1.35 1.40 1.45 0.053 0.055 B 0.17 0.22 0.27 0.007 0.009 C 0.09 0.20 0.0035 0.002 0.006 D 9.00 0.354 7.00 0.276 D3 5.50 0.216 e 0.50 0.020 E 9.00 0.354 E1 7.00 0.276 E3 5.50 0.216 L 0.45 K 0.60 0.75 0.018 1.00 0˚ 3.5˚ 0.057 0.011 0.0079 D1 L1 MAX. 0.024 0.030 0.039 7˚ 0˚ 3.5˚ 7˚ 0110596/C 23/26 Package mechanical data STP24DP05 Figure 21. TQFP48 tape and reel Tape & Reel TQFP48 MECHANICAL DATA mm. inch DIM. MIN. A MAX. MIN. 330 13.2 TYP. MAX. 12.992 C 12.8 D 20.2 0.795 N 60 2.362 T 24/26 TYP 0.504 22.4 0.519 0.882 Ao 9.5 9.7 0.374 0.382 Bo 9.5 9.7 0.374 0.382 Ko 2.1 2.3 0.083 0.091 Po 3.9 4.1 0.153 0.161 P 11.9 12.1 0.468 0.476 STP24DP05 11 Revision history Revision history Table 17. Document revision history Date Revision 19-Apr-2008 1 Changes First release 25/26 STP24DP05 Please Read Carefully: Information in this document is provided solely in connection with ST products. STMicroelectronics NV and its subsidiaries (“ST”) reserve the right to make changes, corrections, modifications or improvements, to this document, and the products and services described herein at any time, without notice. All ST products are sold pursuant to ST’s terms and conditions of sale. Purchasers are solely responsible for the choice, selection and use of the ST products and services described herein, and ST assumes no liability whatsoever relating to the choice, selection or use of the ST products and services described herein. No license, express or implied, by estoppel or otherwise, to any intellectual property rights is granted under this document. If any part of this document refers to any third party products or services it shall not be deemed a license grant by ST for the use of such third party products or services, or any intellectual property contained therein or considered as a warranty covering the use in any manner whatsoever of such third party products or services or any intellectual property contained therein. UNLESS OTHERWISE SET FORTH IN ST’S TERMS AND CONDITIONS OF SALE ST DISCLAIMS ANY EXPRESS OR IMPLIED WARRANTY WITH RESPECT TO THE USE AND/OR SALE OF ST PRODUCTS INCLUDING WITHOUT LIMITATION IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE (AND THEIR EQUIVALENTS UNDER THE LAWS OF ANY JURISDICTION), OR INFRINGEMENT OF ANY PATENT, COPYRIGHT OR OTHER INTELLECTUAL PROPERTY RIGHT. UNLESS EXPRESSLY APPROVED IN WRITING BY AN AUTHORIZED ST REPRESENTATIVE, ST PRODUCTS ARE NOT RECOMMENDED, AUTHORIZED OR WARRANTED FOR USE IN MILITARY, AIR CRAFT, SPACE, LIFE SAVING, OR LIFE SUSTAINING APPLICATIONS, NOR IN PRODUCTS OR SYSTEMS WHERE FAILURE OR MALFUNCTION MAY RESULT IN PERSONAL INJURY, DEATH, OR SEVERE PROPERTY OR ENVIRONMENTAL DAMAGE. ST PRODUCTS WHICH ARE NOT SPECIFIED AS "AUTOMOTIVE GRADE" MAY ONLY BE USED IN AUTOMOTIVE APPLICATIONS AT USER’S OWN RISK. Resale of ST products with provisions different from the statements and/or technical features set forth in this document shall immediately void any warranty granted by ST for the ST product or service described herein and shall not create or extend in any manner whatsoever, any liability of ST. ST and the ST logo are trademarks or registered trademarks of ST in various countries. Information in this document supersedes and replaces all information previously supplied. The ST logo is a registered trademark of STMicroelectronics. All other names are the property of their respective owners. © 2008 STMicroelectronics - All rights reserved STMicroelectronics group of companies Australia - Belgium - Brazil - Canada - China - Czech Republic - Finland - France - Germany - Hong Kong - India - Israel - Italy - Japan Malaysia - Malta - Morocco - Singapore - Spain - Sweden - Switzerland - United Kingdom - United States of America www.st.com 26/26