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philips semiconductors pca9530 2-bit i 2 c led dimmer product data sheet supersedes data of 2004 sep 14 2004 oct 01 integrated circuits
philips semiconductors product data sheet pca9530 2-bit i 2 c led dimmer 2 2004 oct 01 features ? 2 led drivers (on, off, flashing at a programmable rate) ? 2 selectable, fully programmable blink rates (frequency and duty cycle) between 0.591 hz and 152 hz (1.69 seconds and 6.58 milliseconds) ? 256 brightness steps ? input/output not used as led drivers can be used as regular gpios ? internal oscillator requires no external components ? i 2 c interface logic compatible with smbus ? internal power-on reset ? noise filter on scl/sda inputs ? active low reset input ? 2 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, 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: so8, tssop8 (msop8) description the pca9530 is a 2-bit i 2 c and smbus i/o expander optimized for dimming leds in 256 discrete steps for red/green/blue (rgb) color mixing and back light applications. the pca9530 contains an internal oscillator with two user programmable blink rates and duty cycles coupled to the output pwm. the led brightness is controlled by setting the blink rate high enough (> 100 hz) that the blinking can not be seen and then using the duty cycle to vary the amount of time the led is on and thus the average current through the led. the initial setup sequence programs the two blink rates/duty cycles for each individual pwm. from then on, only one command from the bus master is required to turn individual leds on, off, blink rate 1 or blink rate 2. based on the programmed frequency and duty cycle, blink rate 1 and blink rate 2 will cause the leds to appear at a different brightness or blink at periods up to 1.69 second. the open drain outputs directly drive the leds with maximum output sink current of 25 ma per bit and 50 ma per package. to blink leds at periods greater than 1.69 second the bus master (mcu, mpu, dsp, chipset, etc.) must send repeated commands to turn the led on and off as is currently done when using normal i/o expanders like the philips pcf8574 or pca9554. any bits not used for controlling the leds can be used for general purpose parallel input/output (gpio) expansion which provides a simple solution when additional i/o is needed for acpi power switches, sensors, pushbuttons, alarm monitoring, fans, etc. the active low hardware reset pin (reset ) and power-on reset (por) initialize the registers to their default state causing the bits to be set high (led off). one hardware address pin on the pca9530 allows two devices to operate on the same bus. pin configuration 1 2 3 45 6 7 8 a0 led0 led1 v ss v dd sda scl reset sw00926 figure 1. pin configuration pin description pin number symbol function 1 a0 address input 0 2 led0 led driver 0 3 led1 led driver 1 4 v ss supply ground 5 reset active low reset input 6 scl serial clock line 7 sda serial data line 8 v dd supply voltage ordering information packages temperature range order code topside mark drawing number 8-pin plastic so 40 c to +85 c PCA9530D pca9530 sot96-1 8-pin plastic tssop (msop) 40 c to +85 c PCA9530Dp 9530 sot505-1 standard packing quantities and other packaging data are available at www.standardproducts.philips.com/packaging. i 2 c is a trademark of philips semiconductors corporation.
philips semiconductors product data sheet pca9530 2-bit i 2 c led dimmer 2004 oct 01 3 block diagram pwm0 register pwm1 register prescaler 0 register prescaler 1 register i 2 c-bus control ledx a0 input filters scl sda oscillator power-on reset v dd v ss sw02042 1 0 blink0 blink1 reset note: only one i/o shown for clarity led select (lsx) register input register pca9530 figure 2. block diagram
philips semiconductors product data sheet pca9530 2-bit i 2 c led dimmer 2004 oct 01 4 device addressing following a start condition the bus master must output the address of the slave it is accessing. the address of the pca9530 is shown in figure 3. to conserve power, no internal pullup resistor is incorporated on the hardware selectable address pin and it must be pulled high or low. 11 0 000a0 slave address sw00928 fixed hardware selectable r/w figure 3. 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 following the successful acknowledgement of the slave address, the bus master will send a byte to the pca9530 which will be stored in the control register. 0 0 ai b2 b1 b0 0 sw01034 0 auto-increment flag register address reset state: 00h figure 4. 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 the input register (b2 b1 b0 0 0 0). only the 3 least significant bits are affected by the ai flag. unused bits must be programmed with zeroes. control register definition 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 led selector register description input e input register led1 led0 bit 7 6 5 4 3 2 1 0 default 0 0 0 0 0 0 x x the input register reflects the state of the device pins. writes to this register will be acknowledged but will have no effect. note: the default value axo is determined by the externally applied logic level, normally `1' when used for directly driving led with pull-up to v dd . psc0 e frequency prescaler 0 bit 7 6 5 4 3 2 1 0 default 0 0 0 0 0 0 0 0 psc0 is used to program the period of the pwm output. the period of blink0 (psc0 1) 152 pwm0 e 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 low (led on) when the count is less than the value in pwm0 and high (led off) when it is greater. if pwm0 is programmed with 00h, then the pwm0 output is always high (led off). the duty cycle of blink0 is: pwm0 256 psc1 e frequency prescaler 1 bit 7 6 5 4 3 2 1 0 default 0 0 0 0 0 0 0 0 psc1 is used to program the period of pwm output. the period of blink1 (psc1 1) 152
philips semiconductors product data sheet pca9530 2-bit i 2 c led dimmer 2004 oct 01 5 pwm1 e pwm register 1 bit 7 6 5 4 3 2 1 0 default 1 0 0 0 0 0 0 0 the pwm1 register determines the duty cycle of blink1. the outputs are low (led on) when the count is less than the value in pwm1 and high (led off) when it is greater. if pwm1 is programmed with 00h, then the pwm1 output is always high (led off). the duty cycle of blink1 is: pwm1 256 ls0 e led selector led 1 led 0 bit 7 6 5 4 3 2 1 0 default 1 1 1 1 0 0 0 0 the lsx led select registers determine the source of the led data. 00 = output is set hi-z (led off default) 01 = output is set low (led on) 10 = output blinks at pwm0 rate 11 = output blinks at pwm1 rate pins used as general purpose i/os led pins not used to control leds can be used as general purpose i/os. for use as input: set ledx to high-impedance (00) and then read the pin state via the input register. 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 aled selectoro register. the output can be pulse-width controlled when pwm0 or pwm1 are used. power-on reset when power is applied to v dd , an internal power-on reset holds the pca9530 in a reset condition until v dd has reached v por . at this point, the reset condition is released and the pca9530 registers are initialized to their default states, all the outputs in the off state. thereafter, v dd must be lowered below 0.2 v to reset the device. external reset a reset can be accomplished by holding the reset pin low for a minimum of t w . the pca9530 registers and i 2 c state machine will be held in their default state until the reset input is once again high. this input requires a pull-up resistor to v dd if no active connection is used. characteristics of the i 2 c-bus the i 2 c-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. bit transfer 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 5). sda scl sw00363 data line stable; data valid change of data allowed figure 5. bit transfer start and stop conditions 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 6). system configuration 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 7).
philips semiconductors product data sheet pca9530 2-bit i 2 c led dimmer 2004 oct 01 6 sda scl sw00365 s p sda scl start condition stop condition figure 6. definition of start and stop conditions master transmitter/ receiver slave receiver slave transmitter/ receiver master transmitter master transmitter/ receiver sda scl sw00366 i 2 c multiplexer slave figure 7. system configuration acknowledge the number of data bytes transferred between the start and the stop conditions from transmitter to receiver is not limited. eac h 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 ge nerates 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 h as 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 r elated 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 scl from master sw00368 data output by receiver 12 89 s start condition clock pulse for acknowledgement acknowledge not acknowledge figure 8. acknowledgement on the i 2 c-bus
philips semiconductors product data sheet pca9530 2-bit i 2 c led dimmer 2004 oct 01 7 bus transactions 0a0 12 scl write to register data out from port 345678 sda s0a a a 11000 data 1 slave address data to register start condition r/w acknowledge from slave acknowledge from slave acknowledge from slave t pv data 1 valid sw01014 9 b0 0 0 0 ai 0 b2 b1 command byte figure 9. write to register 0 0 0 0 0 0 a0 1 1 0 0 a0 1 1 s0a a a acknowledge from slave r/w acknowledge from slave a p na acknowledge from slave acknowledge from master s data data r/w first byte at this moment master-transmitter becomes master-receiver and slave-receiver becomes slave-transmitter last byte sw01098 no acknowledge from master 1 slave address data from register data from register slave address auto-increment register address if ai = 1 0 0 0 ai 0b2b1b0 figure 10. read from register 110 0 0 0a0 read from port data into port sda s1a a data 1 data 4 slave address data from port data from port start condition r/w acknowledge from slave acknowledge from master stop condition t ps data 4 data 2 p data 3 t ph sw01095 no acknowledge from master na data 1 notes: 1. this figure assumes the command byte has previously been programmed with 00h. figure 11. read input port register
philips semiconductors product data sheet pca9530 2-bit i 2 c led dimmer 2004 oct 01 8 application data pca9530 a0 v ss sda scl reset v dd i 2 c/smbus master sw02043 sda scl led0 led1 3.3 v 5 v 10 k w 10 k w 10 k w figure 12. typical application minimizing i dd when the i/o is used to control leds when the i/os are used to control leds, they are normally connected to v dd through a resistor as shown in figure 12. since the led acts as a diode, when the led is off the i/o v in is about 1.2 v less than v dd . the supply current , i dd , increases as v in becomes lower than v dd and is specified as d i dd in the dc characteristics table. designs needing to minimize current consumption, such as battery power applications, should consider maintaining the i/o pins g reater than or equal to v dd when the led is off. figure 13 shows a high value resistor in parallel with the led. figure 14 shows v dd less than the led supply voltage by at least 1.2 v. both of these methods maintain the i/o v in at or above v dd and prevents additional supply current consumption when the led is off. v dd v dd ledx led 100 k w sw02086 figure 13. high value resistor in parallel with the led v dd 3.3 v ledx led sw02087 5 v figure 14. device supplied by a lower voltage
philips semiconductors product data sheet pca9530 2-bit i 2 c led dimmer 2004 oct 01 9 programming example the following example will show how to set led0 to blink at 1 hz at a 50 % duty cycle. led1 will be set to be dimmed at 25 % of their maximum brightness (duty cycle = 25 %). table 1. i 2 c-bus start s pca9530 address with a0 = low coh psc0 subaddress + auto-increment 11h set prescaler psc0 to achieve a period of 1 second: blink period 1 psc0 1 152 psc0 = 151 97h set pwm0 duty cycle to 50 %: pwm0 256 0.5 pwm0 = 128 80h set prescaler pcs1 to dim at maximum frequency. blink period maximum psc1 = 0 00h set pwm1 output duty cycle to 25 %: pwm1 256 0.25 pwm1 = 64 40h set led0 to pwm0 and set led1 to blink at pwm1 oeh stop p
philips semiconductors product data sheet pca9530 2-bit i 2 c led dimmer 2004 oct 01 10 absolute maximum ratings in accordance with the absolute maximum rating system (iec 134) symbol parameter conditions min max unit v dd supply voltage 0.5 6.0 v v i/o dc voltage on an i/o v ss 0.5 5.5 v i i/o dc output current on an i/o e +25 ma i ss supply current e 50 ma p tot total power dissipation e 400 mw t stg storage temperature range 65 +150 c t amb 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 desirab le to take precautions appropriate to handling mos devices. advice can be found in data handbook ic24 under a handling mos devices o. dc characteristics v dd = 2.3 v to 5.5 v; v ss = 0 v; t amb = 40 c to +85 c; unless otherwise specified. typ at 3.3 v and 25 c. symbol parameter conditions min typ max unit supplies v dd supply voltage 2.3 e 5.5 v i dd supply current operating mode; v dd = 5.5 v; no load; v i = v dd or v ss ; f scl = 100 khz e 350 500 m a i stb standby current standby mode; v dd = 5.5 v; no load; v i = v dd or v ss ; f scl = 0 khz e 1.9 3.0 m a d i dd additional standby current standby mode; v dd = 5.5 v; every led i/o at v in = 4.3 v; f scl = 0 khz e e 200 m a v por power-on reset voltage (note 1) no load; v i = v dd or v ss e 1.7 2.2 v input scl; input/output sda v il low-level input voltage 0.5 e 0.3v dd v v ih high-level input voltage 0.7v dd e 5.5 v i ol low-level output current v ol = 0.4 v 3 6.5 e ma i l leakage current v i = v dd = v ss 1 e +1 m a c i input capacitance v i = v ss e 3.7 5 pf i/os v il low-level input voltage 0.5 e 0.8 v v ih high-level input voltage 2.0 e 5.5 v v ol = 0.4 v; v dd = 2.3 v; note 2 9 e e ma v ol = 0.4 v; v dd = 3.0 v; note 2 12 e e ma i o low level out p ut current v ol = 0.4 v; v dd = 5.0 v; note 2 15 e e ma i ol low - le v el o u tp u t c u rrent v ol = 0.7 v; v dd = 2.3 v; note 2 15 e e ma v ol = 0.7 v; v dd = 3.0 v; note 2 20 e e ma v ol = 0.7 v; v dd = 5.0 v; note 2 25 e e ma i l input leakage current v dd = 3.6 v; v i = 0 v or v dd 1 e 1 m a c io input/output capacitance e 2.1 5 pf select inputs a0 / reset v il low-level input voltage 0.5 e 0.8 v v ih high-level input voltage 2.0 e 5.5 v i li input leakage current 1 e 1 m a c i input capacitance v i = v ss e 2.3 5 pf note: 1. v dd 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 50 ma.
philips semiconductors product data sheet pca9530 2-bit i 2 c led dimmer 2004 oct 01 11 ac specifications symbol parameter standard mode i 2 c-bus fast mode i 2 c-bus units min max min max f scl operating frequency 0 100 0 400 khz t buf bus free time between stop and start conditions 4.7 e 1.3 e m s t hd;sta hold time after (repeated) start condition 4.0 e 0.6 e m s t su;sta repeated start condition setup time 4.7 e 0.6 e m s t su;sto setup time for stop condition 4.0 e 0.6 e m s t hd;dat data in hold time 0 e 0 e ns t vd;ack valid time for ack condition 2 e 600 e 600 ns t vd;dat (l) data out valid time 3 e 600 e 600 ns t vd;dat (h) data out valid time 3 e 1500 e 600 ns t su;dat data setup time 250 e 100 e ns t low clock low period 4.7 e 1.3 e m s t high clock high period 4.0 e 0.6 e m s t f clock/data fall time e 300 20 + 0.1 c b 1 300 ns t r clock/data rise time e 1000 20 + 0.1 c b 1 300 ns t sp pulse width of spikes that must be suppressed by the input filters e 50 e 50 ns port timing t pv output data valid e 200 e 200 ns t ps input data setup time 100 e 100 e ns t ph input data hold time 1 e 1 e m s reset t w reset pulse width 6 e 6 e ns t rec reset recovery time 0 e 0 e ns t reset 4,5 time to reset 400 e 400 e ns notes: 1. c b = total capacitance of one bus line in pf. 2. t vd;ack = time for acknowledgement signal from scl low to sda (out) low. 3. t vd;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 t reset and the rc time constant of the sda bus.
philips semiconductors product data sheet pca9530 2-bit i 2 c led dimmer 2004 oct 01 12 +10% 0% 10% 20% 30% 40% percent variation temperature ( c) 40 +20% 0 +25 +70 +85 max avg min sw01085 figure 15. typical frequency variation over process at v dd = 2.3 v to 3.0 v +10% 0% 10% 20% 30% 40% percent variation temperature ( c) 40 +20% 0 +25 +70 +85 max avg min sw01086 figure 16. typical frequency variation over process at v dd = 3.0 v to 5.5 v
philips semiconductors product data sheet pca9530 2-bit i 2 c led dimmer 2004 oct 01 13 sda scl sw02310 t reset t reset 50% 30% 50% 50% 50% t rec t w reset ledx led off ack or read cycle start figure 17. definition of reset timing t sp t buf t hd;sta p p s t low t r t hd;dat t f t high t su;dat t su;sta sr t hd;sta t su;sto sda scl su00645 figure 18. definition of timing protocol scl sda t hd;sta t su;dat t hd;dat t vd;dat t f r t t buf t su;sta t low t high 1 / f scl start condition (s) bit 7 msb (a7) bit 6 (a6) t vd;ack sw02333 bit 7 (d1) stop condition (p) t su;sto bit 8 (d0) acknowledge (a) figure 19. i 2 c-bus timing diagram; rise and fall times refer to v il and v ih
philips semiconductors product data sheet pca9530 2-bit i 2 c led dimmer 2004 oct 01 14 pulse generator v i v o c l 50 pf v dd definitions r l = load resistor for ledn. r l for sda and scl > 1 k w (3 ma or less current). c l = load capacitance includes jig and probe capacitance r t = termination resistance should be equal to the output impedance z o of the pulse generators. v dd r t open d.u.t. r l = 500 w sw02334 figure 20. test circuitry for switching times
philips semiconductors product data sheet pca9530 2-bit i 2 c led dimmer 2004 oct 01 15 so8: plastic small outline package; 8 leads; body width 3.9 mm sot96-1
philips semiconductors product data sheet pca9530 2-bit i 2 c led dimmer 2004 oct 01 16 tssop8: plastic thin shrink small outline package; 8 leads; body width 3 mm sot505-1
philips semiconductors product data sheet pca9530 2-bit i 2 c led dimmer 2004 oct 01 17 revision history rev date description _2 20041001 product data sheet (9397 750 14093). supersedes data of 2004 sep 14 (9397 750 13631). modifications: ? afeatureso section on page 2: second bullet: change from a... between 0.625 and 160 hz (1.6 seconds and 6.25 milliseconds)o to a... between 0.591 hz and 152 hz (1.69 seconds and 6.58 milliseconds)o last bullet: add a(msop8)o ? adescriptiono section on page 2: third paragraph, third sentence: change from a... or blink at periods up to 1.6 second.o to a... or blink at periods up to 1.69 second.o fourth paragraph, first sentence: change from a... periods greater than 1.6 second ...o to a... periods greater than 1.69 second.o ? ordering information table on page 2: add a(msop)o to table cell `8-pin plastic tssop' ? add note to section ainputeinput registero on page 4 ? add section apins used as general purpose i/oso on page 5. ? figure 12 on page 8: add resistor values ? dc characteristics table on page 10: add d i dd max value (200 m a). ? ac specifications table on page 11: change t vd;ack max value (for both modes) from 900 ns to 600 ns. _1 20040914 product data sheet (9397 750 13631).
philips semiconductors product data sheet pca9530 2-bit i 2 c led dimmer 2004 oct 01 18 purchase of philips i 2 c components conveys a license under the philips' i 2 c patent to use the components in the i 2 c system provided the system conforms to the i 2 c specifications defined by philips. this specification can be ordered using the code 9398 393 40011. definitions short-form specification e the data in a short-form specification is extracted from a full data sheet with the same type number and title. for detailed i nformation see the relevant data sheet or data handbook. limiting values definition e limiting values given are in accordance with the absolute maximum rating system (iec 60134). stress above one or more of the l imiting values may cause permanent damage to the device. these are stress ratings only and operation of the device at these or at any o ther conditions above those given in the characteristics sections of the specification is not implied. exposure to limiting values for extended periods may affec t device reliability. application information e applications that are described herein for any of these products are for illustrative purposes only. philips semiconductors ma ke no representation or warranty that such applications will be suitable for the specified use without further testing or modificatio n. disclaimers life support e these products are not designed for use in life support appliances, devices, or systems where malfunction of these products ca n reasonably be expected to result in personal injury. philips semiconductors customers using or selling these products for use in such applica tions do so at their own risk and agree to fully indemnify philips semiconductors for any damages resulting from such application. right to make changes e philips semiconductors reserves the right to make changes in the productseincluding circuits, standard cells, and/or softwaree 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 th e 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 warranti es that these products are free from patent, copyright, or mask work right infringement, unless otherwise specified. contact information for additional information please visit http://www.semiconductors.philips.com . fax: +31 40 27 24825 for sales offices addresses send e-mail to: sales.addresses@www.semiconductors.philips.com . ? koninklijke philips electronics n.v. 2004 all rights reserved. published in the u.s.a. date of release: 10-04 document number: 9397 750 14093

data sheet status [1] objective data sheet preliminary data sheet product data sheet product status [2] [3] development qualification production definitions 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. 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. 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). data sheet status [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 l atest 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. level i ii iii

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