INTEGRATED CIRCUITS PCA9551 8-bit I2C LED driver with programmable blink rates Product data sheet Supersedes data of 2003 May 05 Philips Semiconductors 2004 Oct 01 Philips Semiconductors Product data sheet 8-bit I2C LED driver with programmable blink rates PCA9551 DESCRIPTION The PCA9551 LED Blinker blinks LEDs in I2C-bus and SMBus applications where it is necessary to limit bus traffic or free up the I2C Master’s (MCU, MPU, DSP, chipset, etc.) timer. The uniqueness of this device is the internal oscillator with two programmable blink rates. To blink LEDs using normal I/O Expanders like the PCF8574 or PCA9554, the bus master must send repeated commands to turn the LED on and off. This greatly increases the amount of traffic on the I2C-bus and uses up one of the master’s timers. The PCA9551 LED Blinker instead requires only the initial set up command to program BLINK RATE 1 and BLINK RATE 2 (i.e., the frequency and duty cycle) for each individual output. From then on, only one command from the bus master is required to turn each individual open drain output ON, OFF, or to cycle at BLINK RATE 1 or BLINK RATE 2. Maximum output sink current is 25 mA per bit and 100 mA per package. FEATURES • 8 LED drivers (on, off, flashing at a programmable rate) • 2 selectable, fully programmable blink rates (frequency and duty cycle) between 0.148 Hz and 38 Hz (6.74 and 0.026 seconds) • Input/outputs not used as LED drivers can be used as regular GPIOs Any bits not used for controlling the LEDs can be used for General Purpose Parallel Input/Output (GPIO) expansion. • Internal oscillator requires no external components • I2C-bus interface logic compatible with SMBus • Internal power-on reset • Noise filter on SCL/SDA inputs • Active-LOW reset input • 8 open drain outputs directly drive LEDs to 25 mA • Edge rate control on outputs • No glitch on power-up • Supports hot insertion • Low stand-by current • Operating power supply voltage range of 2.3 V to 5.5 V • 0 to 400 kHz clock frequency • ESD protection exceeds 2000 V HBM per JESD22-A114, The active-LOW hardware reset pin (RESET) and Power-On Reset (POR) initializes the registers to their default state, all zeroes, causing the bits to be set HIGH (LED off). Three hardware address pins on the PCA9551 allow eight devices to operate on the same bus. 150 V MM per JESD22-A115 and 1000 V CDM per JESD22-C101 • Latch-up testing is done to JESDEC Standard JESD78 which exceeds 100 mA • Packages offered: SO16, TSSOP16, HVQFN16 ORDERING INFORMATION PACKAGES TEMPERATURE RANGE ORDER CODE TOPSIDE MARK DRAWING NUMBER 16-pin plastic SO –40 °C to +85 °C PCA9551D PCA9551D SOT109-1 16-pin plastic TSSOP –40 °C to +85 °C PCA9551PW PCA9551 SOT403-1 16-pin plastic HVQFN –40 °C to +85 °C PCA9551BS 9551 SOT629-1 Standard packing quantities and other packaging data are available at www.standardproducts.philips.com/packaging. I2C is a trademark of Philips Semiconductors Corporation. 2004 Oct 01 2 Philips Semiconductors Product data sheet 8-bit I2C LED driver with programmable blink rates LED0 4 13 RESET LED1 5 12 LED7 LED2 6 11 LED6 LED3 7 10 LED5 9 LED4 A2 1 12 SCL LED0 2 11 RESET LED1 3 10 LED7 LED2 4 9 5 VSS 8 13 14 SCL SDA LED3 LED6 8 A2 3 VDD 14 15 SDA A0 7 A1 2 A1 15 16 VDD 6 A0 1 PIN CONFIGURATION — HVQFN 16 PIN CONFIGURATION — SO, TSSOP PCA9551 VSS LED4 LED5 SW02039 TOP VIEW Figure 1. Pin configuration — SO, TSSOP su01667 Figure 2. Pin configuration — HVQFN PIN DESCRIPTION SO, TSSOP PIN NUMBER HVQFN PIN NUMBER SYMBOL 1 15 A0 Address input 0 2 16 A1 Address input 1 3 1 A2 Address input 2 4, 5, 6, 7 2, 3, 4, 5 LED0 to LED3 LED drivers 0–3 8 6 VSS 9, 10, 11, 12 7, 8, 9, 10 LED4 to LED7 13 11 RESET 14 12 SCL Serial clock line 15 13 SDA Serial data line 16 14 VDD Supply voltage 2004 Oct 01 FUNCTION Supply ground LED drivers 4–7 Active-LOW reset input 3 Philips Semiconductors Product data sheet 8-bit I2C LED driver with programmable blink rates PCA9551 BLOCK DIAGRAM A2 A1 A0 PCA9551 INPUT REGISTER SCL INPUT FILTERS I2C-BUS CONTROL LED SELECT (LSx) REGISTER SDA 0 1 VDD LEDx POWER-ON RESET RESET OSCILLATOR PRESCALER 0 REGISTER PWM0 REGISTER BLINK0 PRESCALER 1 REGISTER PWM1 REGISTER BLINK1 VSS NOTE: ONLY ONE I/O SHOWN FOR CLARITY SW01015 Figure 3. Block diagram 2004 Oct 01 4 Philips Semiconductors Product data sheet 8-bit I2C LED driver with programmable blink rates DEVICE ADDRESSING CONTROL REGISTER DEFINITION Following a START condition the bus master must output the address of the slave it is accessing. The address of the PCA9551 is shown in Figure 4. To conserve power, no internal pull-up resistors are incorporated on the hardware selectable address pins and they must be pulled HIGH or LOW. SLAVE ADDRESS 1 1 0 PCA9551 0 FIXED A2 A1 B2 B1 B0 REGISTER NAME TYPE REGISTER FUNCTION 0 0 0 INPUT READ INPUT REGISTER 0 0 1 PSC0 READ/ WRITE FREQUENCY PRESCALER 0 0 1 0 PWM0 READ/ WRITE PWM REGISTER 0 0 1 1 PSC1 READ/ WRITE FREQUENCY PRESCALER 1 1 0 0 PWM1 READ/ WRITE PWM REGISTER 1 1 0 1 LS0 READ/ WRITE LED0–LED3 SELECTOR 1 1 0 LS1 READ/ WRITE LED4–LED7 SELECTOR A0 R/W HARDWARE SELECTABLE su01420 Figure 4. Slave address The last bit of the address byte defines the operation to be performed. When set to logic 1 a read is selected while a logic 0 selects a write operation. CONTROL REGISTER REGISTER DESCRIPTION Following the successful acknowledgement of the slave address, the bus master will send a byte to the PCA9551 which will be stored in the Control Register. 0 0 0 AI 0 B2 B1 INPUT — INPUT REGISTER LED 7 B0 LED 5 LED 4 LED 3 LED 2 LED 1 LED 0 bit 7 6 5 4 3 2 1 0 default X X X X X X X X The INPUT register reflects the state of the device pins. Writes to this register will be acknowledged but will have no effect. REGISTER ADDRESS RESET STATE: 00h LED 6 NOTE: The default value “X” is determined by the externally applied logic level, normally ‘1’ when used for directly driving LED with pull-up to VDD. AUTO-INCREMENT FLAG SW01034 PSC0 — FREQUENCY PRESCALER 01 Figure 5. Control register The lowest 3 bits are used as a pointer to determine which register will be accessed. If the auto-increment flag is set, the three low order bits of the Control Register are automatically incremented after a read or write. This allows the user to program the registers sequentially. The contents of these bits will rollover to ‘000’ after the last register is accessed. When auto-increment flag is set (AI = 1) and a read sequence is initiated, the sequence must start by reading a register different from ‘0’ (B2 B1 B0 0 0 0 0) Only the 3 least significant bits are affected by the AI flag. Unused bits must be programmed with zeroes. bit 7 6 5 4 3 2 1 0 default 1 1 1 1 1 1 1 1 PSC0 is used to program the period of the PWM output. The period of BLINK0 + (PSC0 ) 1) 38 NOTE: 1. Prescaler calculation is different between the PCA9551 and other PCA955x LED Blinkers. A divider ratio of 38 instead of 44 is used. This different divider ratio causes the blinking frequency to be 13% (1 – 38/44) lower when the same 8-bit word is used. The programmed value of the FREQUENCY PRESCALER must be adjusted to compensate for this difference in applications where the PCA9551 is used in conjunction with other PCA955x LED Blinkers and the observed blinking frequencies need to be the same. PWM0 — PWM REGISTER 0 bit 7 6 5 4 3 2 1 0 default 1 0 0 0 0 0 0 0 The PWM0 register determines the duty cycle of BLINK0. The outputs are HIGH (LED off) when the count is less than the value in PWM0 and HIGH when it is greater. If PWM0 is programmed with 00h, then the PWM0 output is always LOW. The duty cycle of BLINK0 is: 256 – PWM0 256 2004 Oct 01 5 Philips Semiconductors Product data sheet 8-bit I2C LED driver with programmable blink rates PSC1 — FREQUENCY PRESCALER 11 PINS USED AS GENERAL PURPOSE I/Os bit 7 6 5 4 3 2 1 0 default 1 1 1 1 1 1 1 1 LED pins not used to control LEDs can be used as general purpose I/Os. For use as input: Set LEDx to high-impedance (01) and then read the pin state via the input register. PSC1 is used to program the period of PWM output. (PSC1 1) The period of BLINK1 38 NOTE: 1. Prescaler calculation is different between the PCA9551 and other PCA955x LED Blinkers. A divider ratio of 38 instead of 44 is used. This different divider ratio causes the blinking frequency to be 13% (1 – 38/44) lower when the same 8-bit word is used. The programmed value of the FREQUENCY PRESCALER must be adjusted to compensate for this difference in applications where the PCA9551 is used in conjunction with other PCA955x LED Blinkers and the observed blinking frequencies need to be the same. For use as output: Connect external pull-up resistor to the pin and size it according to the DC recommended operating characteristics. LED output pin is HIGH when the output is programmed as high-impedance, and LOW when the output is programmed LOW through the “LED selector” register. The output can be pulse-width controlled when PWM0 or PWM1 are used. POWER-ON RESET When power is applied to VDD, an internal Power-On Reset holds the PCA9551 in a reset condition until VDD has reached VPOR. At this point, the reset condition is released and the PCA9551 registers are initialized to their default states, all the outputs in the off state. Thereafter, VDD must be lowered below 0.2 V to reset the device. PWM1 — PWM REGISTER 1 bit 7 6 5 4 3 2 1 0 default 1 0 0 0 0 0 0 0 EXTERNAL RESET The PWM1 register determines the duty cycle of BLINK1. The outputs are LOW (LED off) when the count is less than the value in PWM1 and HIGH when it is greater. If PWM1 is programmed with 00h, then the PWM1 output is always LOW (LED off). A reset can be accomplished by holding the RESET pin LOW for a minimum of tW. The PCA9551 registers and I2C state machine will be held in their default state until the RESET input is once again HIGH. The duty cycle of BLINK1 is: 256 – PWM1 256 This input requires a pull-up resistor to VDD if no active connection is used. LS0 — LED0–3 SELECTOR LED 3 LED 2 LED 1 LED 0 bit 7 6 5 4 3 2 1 0 default 0 1 0 1 0 1 0 1 LS1 — LED4–7 SELECTOR LED 7 LED 6 LED 5 LED 4 bit 7 6 5 4 3 2 1 0 default 0 1 0 1 0 1 0 1 The LSx LED select registers determine the source of the LED data. 00 = Output is set LOW (LED on) 01 = Output is set Hi-Z (LED off – default) 10 = Output blinks at PWM0 rate 11 = Output blinks at PWM1 rate 2004 Oct 01 PCA9551 6 Philips Semiconductors Product data sheet 8-bit I2C LED driver with programmable blink rates PCA9551 CHARACTERISTICS OF THE I2C-BUS Start and stop conditions The I2C-bus is for 2-way, 2-line communication between different ICs or modules. The two lines are a serial data line (SDA) and a serial clock line (SCL). Both lines must be connected to a positive supply via a pull-up resistor when connected to the output stages of a device. Data transfer may be initiated only when the bus is not busy. Both data and clock lines remain HIGH when the bus is not busy. A HIGH-to-LOW transition of the data line, while the clock is HIGH is defined as the start condition (S). A LOW-to-HIGH transition of the data line while the clock is HIGH is defined as the stop condition (P) (see Figure 7). Bit transfer System configuration One data bit is transferred during each clock pulse. The data on the SDA line must remain stable during the HIGH period of the clock pulse as changes in the data line at this time will be interpreted as control signals (see Figure 6). A device generating a message is a transmitter: a device receiving is the receiver. The device that controls the message is the master and the devices which are controlled by the master are the slaves (see Figure 8). SDA SCL data line stable; data valid change of data allowed SW00363 Figure 6. Bit transfer SDA SDA SCL SCL S P START condition STOP condition SW00365 Figure 7. Definition of start and stop conditions SDA SCL MASTER TRANSMITTER/ RECEIVER SLAVE RECEIVER SLAVE TRANSMITTER/ RECEIVER MASTER TRANSMITTER MASTER TRANSMITTER/ RECEIVER I2C MULTIPLEXER SLAVE SW00366 Figure 8. System configuration 2004 Oct 01 7 Philips Semiconductors Product data sheet 8-bit I2C LED driver with programmable blink rates PCA9551 Acknowledge The number of data bytes transferred between the start and the stop conditions from transmitter to receiver is not limited. Each byte of eight bits is followed by one acknowledge bit. The acknowledge bit is a HIGH level put on the bus by the transmitter whereas the master generates an extra acknowledge related clock pulse. A slave receiver which is addressed must generate an acknowledge after the reception of each byte. Also a master must generate an acknowledge after the reception of each byte that has been clocked out of the slave transmitter. The device that acknowledges has to pull down the SDA line during the acknowledge clock pulse, so that the SDA line is stable LOW during the HIGH period of the acknowledge related clock pulse, set-up and hold times must be taken into account. A master receiver must signal an end of data to the transmitter by not generating an acknowledge on the last byte that has been clocked out of the slave. In this event, the transmitter must leave the data line HIGH to enable the master to generate a stop condition. DATA OUTPUT BY TRANSMITTER not acknowledge DATA OUTPUT BY RECEIVER acknowledge SCL FROM MASTER 1 2 8 9 S clock pulse for acknowledgement START condition SW00368 Figure 9. Acknowledgement on the 2004 Oct 01 8 I2C-bus Philips Semiconductors Product data sheet 8-bit I2C LED driver with programmable blink rates PCA9551 Bus transactions 1 SCL 2 3 4 5 6 7 8 9 command byte slave address SDA S 1 1 0 0 A2 A1 A0 start condition 0 R/W A 0 0 0 AI 0 data to register B2 B1 B0 acknowledge from slave DATA 1 A A acknowledge from slave acknowledge from slave WRITE TO REGISTER DATA OUT FROM PORT DATA 1 VALID tpv SW01081 Figure 10. WRITE to register acknowledge from slave slave address S 1 1 0 0 A2 A1 A0 A 0 acknowledge from slave 0 0 0 AI 0 B2 B1 B0 A S acknowledge from slave slave address 1 1 0 0 A2 A1 R/W A0 1 acknowledge from master data from register DATA A A first byte R/W auto-increment register address if AI = 1 at this moment master-transmitter becomes master-receiver and slave-receiver becomes slave-transmitter data from register no acknowledge from master NA DATA P last byte SW01082 Figure 11. READ from register slave address SDA S 1 1 0 0 start condition A2 data from port A1 A0 1 R/W data from port DATA 1 A A acknowledge from slave DATA 4 acknowledge from master NA no acknowledge from master P stop condition READ FROM PORT DATA INTO PORT DATA 1 DATA 2 DATA 3 tph DATA 4 tps SW01084 NOTES: 1. This figure assumes the command byte has previously been programmed with 00h. Figure 12. READ input port register 2004 Oct 01 9 Philips Semiconductors Product data sheet 8-bit I2C LED driver with programmable blink rates PCA9551 APPLICATION DATA 5V 5V 10 kΩ 10 kΩ 10 kΩ VDD SDA SDA LED0 SCL SCL LED1 RESET LED2 LED3 LED4 LED5 LED6 I2C/SMBus MASTER GPIO LED7 A2 A1 A0 Note: LED0 to LED5 are used as LED drivers LED6 and LED7 are used as regular GPIOs. VSS PCA9551 SW00899 Figure 13. Typical application Minimizing IDD when the I/O is used to control LEDs When the I/Os are used to control LEDs, they are normally connected to VDD through a resistor as shown in Figure 13. Since the LED acts as a diode, when the LED is off the I/O VIN is about 1.2 V less than VDD. The supply current, IDD, increases as VIN becomes lower than VDD and is specified as ∆IDD in the DC characteristics table. Designs needing to minimize current consumption, such as battery power applications, should consider maintaining the I/O pins greater than or equal to VDD when the LED is off. Figure 14 shows a high value resistor in parallel with the LED. Figure 15 shows VDD less than the LED supply voltage by at least 1.2 V. Both of these methods maintain the I/O VIN at or above VDD and prevents additional supply current consumption when the LED is off. 3.3 V VDD LED 100 kΩ VDD VDD LEDx LED LEDx SW02086 SW02087 Figure 14. High value resistor in parallel with the LED 2004 Oct 01 5V Figure 15. Device supplied by a lower voltage 10 Philips Semiconductors Product data sheet 8-bit I2C LED driver with programmable blink rates Programming example The following example will show how to set LED0 to LED3 on. It will then set LED4 and LED5 to blink at 1 Hz at a 50% duty cycle. LED6 and LED7 will be set to blink at 4 Hz and at a 25% duty cycle. Table 1. I2C-bus Start S PCA9551 address with A0–A2 = LOW C0h PSC0 subaddress + auto-increment 11h Set prescaler PSC0 to achieve a period of 1 second: 1 Blink period 1 PSC0 38 PSC0 = 37 25h Set PWM0 duty cycle to 50%: 80h 256 – PWM0 0.5 256 PWM0 = 128 Set prescaler PCS1 to achieve a period of 0.25 seconds: 1 Blink period 0.25 PSC1 38 PSC1 = 9 09h Set PWM1 output duty cycle to 25%: C0h 256 – PWM1 0.25 256 PWM1 = 192 Set LED0 to LED3 on 00h Set LED4 and 5 to PWM0, and LED6 or 7 to PWM1 FAh Stop P 2004 Oct 01 11 PCA9551 Philips Semiconductors Product data sheet 8-bit I2C LED driver with programmable blink rates PCA9551 ABSOLUTE MAXIMUM RATINGS In accordance with the Absolute Maximum Rating System (IEC 134) SYMBOL PARAMETER MIN MAX UNIT –0.5 6.0 V VSS – 0.5 5.5 V DC output current on an I/O — ±25 mA VDD Supply voltage VI/O DC voltage on an I/O II/O CONDITIONS ISS Supply current — 100 mA Ptot Total power dissipation — 400 mW Tstg Storage temperature range –65 +150 °C Tamb Operating ambient temperature –40 +85 °C HANDLING Inputs and outputs are protected against electrostatic discharge in normal handling. However, to be totally safe, it is desirable to take precautions appropriate to handling MOS devices. Advice can be found in Data Handbook IC24 under ”Handling MOS devices”. DC CHARACTERISTICS VDD = 2.3 V to 5.5 V; VSS = 0 V; Tamb = –40 °C to +85 °C; unless otherwise specified. TYP at 3.3 V and 25 °C. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNIT 2.3 — 5.5 V Supplies VDD Supply voltage IDD Supply current Operating mode; VDD = 5.5 V; VI = VDD or VSS; fSCL = 100 kHz — 350 500 µA Istb Standby current Standby mode; VDD = 5.5 V; VI = VDD or VSS; fSCL = 0 kHz — 1.9 3.0 µA ∆IDD Additional standby current Standby mode; VDD = 5.5 V; Every LED I/O at VIN = 4.3 V; fSCL = 0 kHz — — 800 µA VPOR Power-on reset voltage (Note 1) No load; VI = VDD or VSS — 1.7 2.2 V Input SCL; input/output SDA VIL LOW-level input voltage –0.5 — 0.3 VDD V VIH HIGH-level input voltage 0.7 VDD — 5.5 V IOL LOW-level output current VOL = 0.4 V 3 6.5 — mA IL Leakage current VI = VDD = VSS –1 — +1 µA CI Input capacitance VI = VSS — 3.7 5 pF VIL LOW-level input voltage –0.5 — 0.8 V VIH HIGH-level input voltage 2.0 — 5.5 V 6 9 — mA I/Os VOL = 0.4 V; VDD = 2.3 V; Note 2 IOL O IL CIO LOW level output current LOW-level Input leakage current VOL = 0.4 V; VDD = 3.0 V; Note 2 8 11 — mA VOL = 0.4 V; VDD = 5.0 V; Note 2 10 14 — mA VOL = 0.7 V; VDD = 2.3 V; Note 2 11 14 — mA VOL = 0.7 V; VDD = 3.0 V; Note 2 14 18 — mA VOL = 0.7 V; VDD = 5.0 V; Note 2 17 24 — mA VDD = 3.6 V; VI = 0 or VDD –1 — 1 µA — 2.1 5 pF Input/output capacitance Select Inputs A0, A1, A2 / RESET VIL LOW-level input voltage –0.5 — 0.8 V VIH HIGH-level input voltage; A0 / RESET 2.0 — 5.5 V VIH HIGH-level input voltage; A1 / A2 2.0 — VDD + 0.5 V ILI Input leakage current –1 — 1 µA CI Input capacitance — 2.3 5 pF VI = VSS NOTES: 1. VDD must be lowered to 0.2 V in order to reset part. 2. Each I/O must be externally limited to a maximum of 25 mA and the device must be limited to a maximum current of 100 mA. 2004 Oct 01 12 Philips Semiconductors Product data sheet 8-bit I2C LED driver with programmable blink rates PCA9551 AC SPECIFICATIONS SYMBOL STANDARD MODE I2C-BUS PARAMETER fSCL Operating frequency tBUF FAST MODE I2C-BUS UNITS MIN MAX MIN MAX 0 100 0 400 kHz Bus free time between STOP and START conditions 4.7 — 1.3 — µs tHD;STA Hold time after (repeated) START condition 4.0 — 0.6 — µs tSU;STA Repeated START condition set-up time 4.7 — 0.6 — µs tSU;STO Set-up time for STOP condition 4.0 — 0.6 — µs tHD;DAT Data in hold time 0 — 0 — ns tVD;ACK — 600 — 600 ns tVD;DAT (L) Data out valid time3 — 600 — 600 ns tVD;DAT (H) Data out valid time3 — 1500 — 600 ns tSU;DAT Valid time for ACK condition2 Data set-up time 250 — 100 — ns tLOW Clock LOW period 4.7 — 1.3 — µs tHIGH Clock HIGH period 4.0 — 0.6 — µs 1 tF Clock/Data fall time — 300 20 + 0.1 Cb 300 ns tR Clock/Data rise time — 1000 20 + 0.1 Cb1 300 ns tSP Pulse width of spikes that must be suppressed by the input filters — 50 — 50 ns ns Port Timing tPV Output data valid tPS Input data set-up time — 200 — 200 100 — 100 — tPH ns Input data hold time 1 — 1 — µs Reset pulse width 6 — 6 — ns 0 — 0 — ns 400 — 400 — ns Reset tW tREC tRESET4,5 Reset recovery time Time to reset NOTES: 1. Cb = total capacitance of one bus line in pF. 2. tVD;ACK = time for Acknowledgement signal from SCL LOW to SDA (out) LOW. 3. tVD;DAT = minimum time for SDA data out to be valid following SCL LOW. 4. Resetting the device while actively communicating on the bus may cause glitches or errant STOP conditions. 5. Upon reset, the full delay will be the sum of tRESET and the RC time constant of the SDA bus. 2004 Oct 01 13 Philips Semiconductors Product data sheet 8-bit I2C LED driver with programmable blink rates PCA9551 +20% MAX +10% 0% PERCENT VARIATION –10% AVG –20% –30% MIN –40% –40 0 +25 +70 +85 TEMPERATURE (°C) SW02311 Figure 16. Typical frequency variation over process at VDD = 2.3 V to 3.0 V +20% MAX +10% 0% PERCENT VARIATION AVG –10% –20% MIN –30% –40% –40 0 +25 +70 +85 TEMPERATURE (°C) Figure 17. Typical frequency variation over process at VDD = 3.0 V to 5.5 V 2004 Oct 01 14 SW02312 Philips Semiconductors Product data sheet 8-bit I2C LED driver with programmable blink rates PCA9551 START SCL ACK OR READ CYCLE SDA 30% tRESET RESET 50% 50% 50% tREC tW tRESET 50% LEDx LED OFF SW02310 Figure 18. Definition of RESET timing SDA tBUF tR tLOW tF tHD;STA tSP SCL tHD;STA P tSU;STA tHD;DAT S tHIGH tSU;DAT tSU;STO Sr P SU00645 Figure 19. Definition of timing BIT 7 MSB (A7) START CONDITION (S) PROTOCOL t t SU;STA LOW BIT 6 (A6) t HIGH BIT 8 (D0) BIT 7 (D1) ACKNOWLEDGE (A) STOP CONDITION (P) 1 / f SCL SCL t t tr BUF f SDA t t HD;STA Figure 20. 2004 Oct 01 I2C-bus SU;DAT t HD;DAT t VD;DAT t VD;ACK timing diagram; rise and fall times refer to VIL and VIH 15 t SU;STO SW02333 Philips Semiconductors Product data sheet 8-bit I2C LED driver with programmable blink rates VDD PCA9551 VDD Open RL = 500 Ω VI VO PULSE GENERATOR D.U.T. RT CL 50 pF DEFINITIONS RL = Load resistor FOR LEDN. RL FOR SDA AND SCL > 1 kΩ (3 mA or less current). CL = Load capacitance includes jig and probe capacitance RT = Termination resistance should be equal to the output impedance ZO of the pulse generators. Figure 21. Test circuitry for switching times 2004 Oct 01 16 SW02334 Philips Semiconductors Product data sheet 8-bit I2C LED driver with programmable blink rates SO16: plastic small outline package; 16 leads; body width 3.9 mm 2004 Oct 01 17 PCA9551 SOT109-1 Philips Semiconductors Product data sheet 8-bit I2C LED driver with programmable blink rates TSSOP16: plastic thin shrink small outline package; 16 leads; body width 4.4 mm 2004 Oct 01 18 PCA9551 SOT403-1 Philips Semiconductors Product data sheet 8-bit I2C LED driver with programmable blink rates HVQFN16: plastic thermal enhanced very thin quad flat package; no leads; 16 terminals; body 4 x 4 x 0.85 mm 2004 Oct 01 19 PCA9551 SOT629-1 Philips Semiconductors Product data sheet 8-bit I2C LED driver with programmable blink rates PCA9551 REVISION HISTORY Rev Date Description _5 20041001 Product data sheet (9397 750 13726). Supersedes data of 2003 May 05 (9397 750 11462). Modifications: • “Features” section on page 2: – second bullet: change from “... between 0.15625 and 40 Hz (6.4 and 0.025 seconds)” to “... between 0.148 Hz and 38 Hz (6.74 and 0.026 seconds)” • “Register description” section on page 5: – section “PCS0—Frequency Prescaler 0”: remove “... and PCA953x LED Dimmers” from Note 1 (2 places). – section “PCS1—Frequency Prescaler 1”: remove “... and PCA953x LED Dimmers” from Note 1 (2 places). • Add note to section “Input—Input Register” on page 5 • Add section “Pins used as General Purpose I/Os” on page 6. • Section “Power-on Reset” on page 6 re-written. • Section “External Reset” on page 6: second paragraph changed from “This input requires a pull-up resistor to VDD.” to “This input requires a pull-up resistor to VDD if no active connection is used.”. • Figure 13 on page 10: add resistor values • DC Characteristics table on page 12: add (new) Note 1 and its reference at VPOR. • Add Figures 20 and 21. _4 20030505 Product data (9397 750 11462); ECN 853-2343 29858 dated 24 April 2003. Supersedes data of 24 February 2003 (9397 750 11155). _3 20030224 Product data (9397 750 11155); ECN 853-2343 29331 of 20 December 2002; supersedes data of 2002 Sep 09 (9397 750 10328). _2 20020927 Product data (9397 750 10328); ECN 853-2343 28878 of 09 September 2002. 2004 Oct 01 20 Philips Semiconductors Product data sheet 8-bit I2C LED driver with programmable blink rates PCA9551 Purchase of Philips I2C components conveys a license under the Philips’ I2C patent to use the components in the I2C system provided the system conforms to the I2C specifications defined by Philips. This specification can be ordered using the code 9398 393 40011. Data sheet status Level Data sheet status [1] Product status [2] [3] Definitions I Objective data sheet Development This data sheet contains data from the objective specification for product development. Philips Semiconductors reserves the right to change the specification in any manner without notice. II Preliminary data sheet Qualification This data sheet contains data from the preliminary specification. Supplementary data will be published at a later date. Philips Semiconductors reserves the right to change the specification without notice, in order to improve the design and supply the best possible product. III Product data sheet Production This data sheet contains data from the product specification. Philips Semiconductors reserves the right to make changes at any time in order to improve the design, manufacturing and supply. Relevant changes will be communicated via a Customer Product/Process Change Notification (CPCN). [1] Please consult the most recently issued data sheet before initiating or completing a design. [2] The product status of the device(s) described in this data sheet may have changed since this data sheet was published. The latest information is available on the Internet at URL http://www.semiconductors.philips.com. [3] For data sheets describing multiple type numbers, the highest-level product status determines the data sheet status. Definitions Short-form specification — The data in a short-form specification is extracted from a full data sheet with the same type number and title. For detailed information see the relevant data sheet or data handbook. Limiting values definition — Limiting values given are in accordance with the Absolute Maximum Rating System (IEC 60134). Stress above one or more of the limiting values may cause permanent damage to the device. These are stress ratings only and operation of the device at these or at any other conditions above those given in the Characteristics sections of the specification is not implied. Exposure to limiting values for extended periods may affect device reliability. Application information — Applications that are described herein for any of these products are for illustrative purposes only. Philips Semiconductors make no representation or warranty that such applications will be suitable for the specified use without further testing or modification. Disclaimers Life support — These products are not designed for use in life support appliances, devices, or systems where malfunction of these products can reasonably be expected to result in personal injury. Philips Semiconductors customers using or selling these products for use in such applications do so at their own risk and agree to fully indemnify Philips Semiconductors for any damages resulting from such application. Right to make changes — Philips Semiconductors reserves the right to make changes in the products—including circuits, standard cells, and/or software—described or contained herein in order to improve design and/or performance. When the product is in full production (status ‘Production’), relevant changes will be communicated via a Customer Product/Process Change Notification (CPCN). Philips Semiconductors assumes no responsibility or liability for the use of any of these products, conveys no license or title under any patent, copyright, or mask work right to these products, and makes no representations or warranties that these products are free from patent, copyright, or mask work right infringement, unless otherwise specified. Koninklijke Philips Electronics N.V. 2004 All rights reserved. Printed in U.S.A. Contact information For additional information please visit http://www.semiconductors.philips.com. Fax: +31 40 27 24825 Date of release: 10-04 For sales offices addresses send e-mail to: [email protected]. Document number: Philips Semiconductors 2004 Oct 01 21 9397 750 13726