PCA9922 8-channel constant current LED driver with output error detection Rev. 01 — 15 January 2009 Product data sheet 1. General description The PCA9922 is an 8-channel constant current LED driver designed for LED signage and display applications. The output current is adjustable from 15 mA to 60 mA controlled by an external series resistor. The outputs are controlled via a serial interface with a maximum clock frequency of 25 MHz to allow for the system requirement of high volume data transmission. Each of the 8 channel outputs has edge rate control to limit the change in current when the outputs are enabled or disabled. The device has built-in circuitry for detecting LED open-circuit and output short to ground. After signaling the specified error detect sequence on the input control lines, error status can be read out of the device via the serial data out. The device is designed such that it may be cascaded with other similar devices. The SDO pin contains the output of the shift register which may be used for cascading to the SDI pin of the next device in the series. SDO changes state on the falling edge of CLK. SDI captures data on the rising edge of CLK. The PCA9922 is a pin-to-pin functionally equivalent 5 V alternative (exception: error data is inverted; see Section 7.2.1, Section 7.2.2 and Section 7.2.7) for the ST2221A and STP08CDC596. The PCA9922 is available in DIP16, TSSOP16 and HVQFN20 packages and is specified over the −40 °C to +85 °C industrial temperature range. 2. Features n n n n n n n n n n n n 25 MHz serial interface 3.3 V to 5.5 V operation 8 LED low side constant current outputs Global control for the 8 LED outputs variable between 15 mA to 60 mA 15 mA to 60 mA maximum current for all 8 output channels set by an external resistor Constant current matching at 25 °C, VDD = 5.0 V Bit-to-bit: ±6 % Chip-to-chip: ±10 % Gradual turn-on/turn-off output to limit EMI Error detection mode for line open, output short to ground, LED open and LED short −40 °C to +85 °C operation ESD protection exceeds 2000 V HBM per JESD22-A114, 200 V MM per JESD22-A115, and 1000 V CDM per JESD22-C101 n Latch-up testing is done to JEDEC Standard JESD78 which exceeds 100 mA PCA9922 NXP Semiconductors 8-channel constant current LED driver with output error detection n Packages offered: DIP16, TSSOP16, HVQFN20 3. Applications n n n n Full color, multi-color, monochrome LED signs LED billboard displays Traffic display signs Transportation and commercial LED signs 4. Ordering information Table 1. Ordering information Type number Package Name Description Version PCA9922N DIP16 plastic dual in-line package; 16 leads (300 mil) SOT38-4 PCA9922PW TSSOP16 plastic thin shrink small outline package; 16 leads; body width 4.4 mm SOT403-1 PCA9922BS HVQFN20 plastic thermal enhanced very thin quad flat package; no leads; 20 terminals; body 5 × 5 × 0.85 mm SOT662-1 4.1 Ordering options Table 2. Ordering options Type number Topside mark Temperature range PCA9922N PCA9922N Tamb = −40 °C to +85 °C PCA9922PW PCA9922 Tamb = −40 °C to +85 °C PCA9922BS P9922 Tamb = −40 °C to +85 °C PCA9922_1 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 01 — 15 January 2009 2 of 26 PCA9922 NXP Semiconductors 8-channel constant current LED driver with output error detection 5. Block diagram LED0 LED1 LED7 VDD ERROR DETECT CURRENT REGULATOR R_EXT VDD PCA9922 OE OUTPUT ENABLE LE 8× DATA LATCH AUTO SHUTDOWN AND AUTO POWER-UP VSS SDI 8× SHIFT REGISTER SDO CLK VSS ERROR CONTROL 002aad311 Fig 1. Block diagram of PCA9922 PCA9922_1 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 01 — 15 January 2009 3 of 26 PCA9922 NXP Semiconductors 8-channel constant current LED driver with output error detection 6. Pinning information 6.1 Pinning VSS 1 16 VDD SDI 2 15 R_EXT CLK 3 14 SDO LE/DM1 4 13 OE/DM2 VSS 1 16 VDD SDI 2 15 R_EXT CLK 3 14 SDO LE/DM1 4 LED0 5 LED1 6 11 LED6 LED2 7 10 LED5 LED3 8 PCA9922N LED0 LED1 LED2 LED3 12 LED7 5 11 LED6 6 10 LED5 7 9 8 LED4 PCA9922PW 12 LED7 9 002aad161 LED4 002aad163 Pin configuration for TSSOP16 16 R_EXT 17 VDD 18 n.c. terminal 1 index area 19 VSS Fig 3. 20 SDI Pin configuration for DIP16 CLK 1 15 SDO LE/DM1 2 LED0 3 LED1 4 12 LED6 LED2 5 11 LED5 14 OE/DM2 7 8 9 n.c. n.c. n.c. 13 LED7 LED4 10 6 PCA9922BS LED3 Fig 2. 13 OE/DM2 002aad349 Transparent top view Fig 4. Pin configuration for HVQFN20 PCA9922_1 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 01 — 15 January 2009 4 of 26 PCA9922 NXP Semiconductors 8-channel constant current LED driver with output error detection 6.2 Pin description Table 3. Pin description I = input; O = output. Symbol Pin Type Description DIP16, TSSOP16 HVQFN20 VSS 1 19[1] power supply supply ground SDI 2 20 I serial data in CLK 3 1 I serial data clock used to shift data on SDI into the shift register LE/DM1 4 2 I latch enable with internal pull-down resistor; active HIGH signal used to capture data in the shift register to present to the outputs Detection Mode 1 LED0 5 3 O constant current LED output driver 0 LED1 6 4 O constant current LED output driver 1 LED2 7 5 O constant current LED output driver 2 LED3 8 6 O constant current LED output driver 3 LED4 9 10 O constant current LED output driver 4 LED5 10 11 O constant current LED output driver 5 LED6 11 12 O constant current LED output driver 6 LED7 12 13 O constant current LED output driver 7 OE/DM2 13 14 I output enable with internal pull-up resistor; active LOW signal used to allow data captured in the latch to be presented to the constant current outputs SDO 14 15 O serial data output R_EXT 15 16 analog input external resistor input VDD 16 17 power supply supply voltage n.c. - 7, 8, 9, 18 - not connected Detection Mode 2 [1] HVQFN20 package die supply ground is connected to both VSS pin and exposed center pad. VSS pin must be connected to supply ground for proper device operation. For enhanced thermal, electrical, and board level performance, the exposed pad needs to be soldered to the board using a corresponding thermal pad on the board and for proper heat conduction through the board, thermal vias need to be incorporated in the PCB in the thermal pad region. PCA9922_1 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 01 — 15 January 2009 5 of 26 PCA9922 NXP Semiconductors 8-channel constant current LED driver with output error detection 7. Functional description The PCA9922 is an 8-channel constant current LED driver with built-in LED output error detection. The PCA9922 contains an 8-bit shift register and data latches, which convert serial input data into parallel output data. At the output stage, 8 regulated current sinks are designed to provide constant and uniform current through LEDs with different forward voltages (VF). Refer to Figure 1 “Block diagram of PCA9922”. 7.1 System interface During normal operation, serial data can be transferred into the PCA9922 through SDI, shifted into the shift register, and out through the SDO. Data shifts from the SDI pin into the next sequential bit in the shift register on each rising edge of the CLK input. The MSB is the first bit to be clocked in. Data shifts out of the shift register and is presented on the SDO pin on the falling edge of CLK. The exception to this is during the error detect sequence, at which time the error status is loaded in a parallel fashion into the shift register. The shift register is never disabled. It is either shifting or it is loading the error status on every rising edge of CLK. Additionally, the device is designed such that it may be cascaded with other similar devices. The SDO pin contains the output of the shift register which may be used for cascading to the SDI pin of the next device in the series. Data is parallel loaded from the serial shift register to an output control register when LE (Latch Enable) is asserted HIGH (serial-to-parallel conversion). The output control register will continue to reflect the shift register data, even if changes occur in the shift register data, as long as LE is HIGH. When LE is LOW the latch is closed and changes in the shift register data no longer effect the output control register. Applications where the latches are bypassed (LE tied HIGH) will require that the OE input be HIGH during serial data entry. The data in the output control register is then used to drive the constant current output drivers when the outputs are enabled. The outputs are globally enabled or disabled through the OE. A LOW level on the OE will enable the output drivers, LED0 to LED7, to reflect the data contained in the output control register. An example timing diagram of expected normal operation of the device is shown in Figure 5. Remark: It is recommended that OE and LE pulse widths be at least two clocks wide when CLK is running to avoid inadvertent entry into the error detect modes. There is no synchronization logic in the design between CLK, LE and OE. It is the user’s responsibility to meet the timing presented in Table 10 in order to guarantee proper operation. PCA9922_1 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 01 — 15 January 2009 6 of 26 PCA9922 NXP Semiconductors 8-channel constant current LED driver with output error detection CLK SDI LE OE LED0 LED1 LED2 LED3 LED4 LED5 LED6 LED7 002aad203 For each LEDn 0 is on, 1 is off. Fig 5. Normal function timing diagram 7.2 LED output error detection The PCA9922 has built-in circuitry for detecting LED open-circuit and output short conditions. A predefined set of signal sequence on the input control lines must be initiated to perform the output error detection. Once the error data is captured by this sequence, error status can be read out of the device via the serial interface. The error detection mode is entered by the user via specific timing sequences presented on the CLK, OE and LE pins. There are three key sequences to be generated by the user: enter error detect, capture faults, and exit error detect. It is the responsibility of the user to enable all outputs that the user wants to test during the error detect sequence. Performing an error mode detection sequence consists of several operations: 1. Entering error detect mode. 2. Setting all bits that you want to test by enabling all outputs to logical 1s in the output latch. 3. Capture fault data. 4. Exit error detect. 7.2.1 Open-circuit detection principle The LED open-circuit detection compares the effective current level IO with the open load detection threshold current Ith(det). If IO is below Ith(det), the PCA9922 detects an open-load condition. This error status can be read as an error status code in the error detect mode. For open-circuit error detection, a channel must be on. PCA9922_1 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 01 — 15 January 2009 7 of 26 PCA9922 NXP Semiconductors 8-channel constant current LED driver with output error detection Table 4. Open-circuit detection State of output port Condition of output current Error status code Meaning off IO = 0 mA 0 detection not possible on IO < Ith(det)[1] 1 open circuit IO ≥ channel n error status bit 0 normal [1] Ith(det)[1] Ith(det) = 0.5 × IO (target) (typical). 7.2.2 Short-circuit detection principle The LED short-circuit detection compares the effective voltage level (VO) with the shorted-load detection threshold voltages Vth(det)sc and Vth(norm). If VO is above the Vth(det)sc threshold, the PCA9922 detects a shorted-load condition. If VO is below the Vth(norm) threshold, no error is detected or error bit is reset. This error status can be read as an error status code in the Special mode. For short-circuit error detection, a channel must be on. Table 5. Shorted-load detection State of output port Condition of output voltage Error status code Meaning off IO = 0 mA 0 detection not possible VO ≥ Vth(det)sc 1 short circuit VO < Vth(norm) channel n error status bit 0 normal on 7.2.3 Entering error detect mode Entering the error detect mode consists of a 5-clock sequence involving CLK, OE and LE as shown in Figure 6. The user must meet the set-up and hold times for OE and LE as detailed inTable 10 to guarantee proper operation of the error detect circuitry. It should be noted that the act of driving LE HIGH around the rising edge of clock 4 opens the latch in the current control register block and data captured in the shift register at that point in time is moved into the output control register. It should also be noted that the output logic was enabled for a brief period of time while OE is LOW around the rising edge of clock 2. The outputs LED[7:0] will glitch during this period. CLK LE OE 002aad204 Fig 6. Timing for ‘Enter Error Detect Mode’ command PCA9922_1 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 01 — 15 January 2009 8 of 26 PCA9922 NXP Semiconductors 8-channel constant current LED driver with output error detection 7.2.4 Setting the outputs to test Before the Capture Fault sequence may be performed, the outputs must be set up. A logic HIGH must be sent to the output control register for all eight bits. This is done after the Enter Error Detect sequence is performed as a normal data load sequence as seen in Figure 5. Please note that this process is completely destructive to the data that is stored in the output control register (and the LED[7:0] pins). The output control register will have to be restored to its proper values by the user after the error detect sequence has been completed. 7.2.5 Capturing the fault/output error data The Capture Fault/Error Data sequence can only follow the Enter Error Detect sequence. If the Error Detect sequence has not occurred, this sequence will be treated as a normal operational sequence. Once the Capture Fault sequence has occurred, an Exit Error Detect sequence should be performed. There can be no more Capture Sequences until another Enter Error Detect sequence has occurred. The Capture Fault Sequence consists of holding OE LOW for no less than 3 clocks (CLK) and for a minimum of 2 µs, whichever is longer. During this period of time, the shift register is being loaded with the fault status. As such, data presented to the device via SDI will not be captured. Bit 7 of the fault data will be present on SDO by the first falling edge CLK after the user de-asserts OE for this cycle. An error condition is output as a 1 (HIGH bit), and a 0 (LOW bit) designates a normal status. Timing for this sequence is shown in Figure 7. CLK LE OE OE = 1'b0 for minimum of 3 clocks or 2 µs, whichever is longer SDO previous serial data fault data MSB resume shift with fault data Fig 7. Timing for ‘Capture Fault Mode’ command PCA9922_1 Product data sheet 002aad205 © NXP B.V. 2009. All rights reserved. Rev. 01 — 15 January 2009 9 of 26 PCA9922 NXP Semiconductors 8-channel constant current LED driver with output error detection 7.2.6 Exit error detect mode The ‘Exit error detect mode’ sequence is used to exit the error detect mode of operation and resume normal mode. This is a 5-clock timing sequence using CLK, OE and LE. This sequence consists of LE being held inactive for all five clocks. OE is active in the second clock for one and only one clock. Figure 8 shows the timing for this sequence. CLK LE OE 002aad206 Fig 8. Timing for ‘Exit Error Detect Mode’ command 7.2.7 Error detection data The PCA9922 will return a logical 1 for each output pin that has an error condition detected as described in Table 4 and Table 5. An error condition may be either an open circuit or short-circuit at the output pin. Once the Capture Fault sequence has completed, the resultant fault/output error data may be shifted out of the device by issuing 8 clocks and reading the data at the SDO pin. If more than one device is connected in series, then more than 8 clocks will be needed to shift all of the data from all of the devices through to the last SDO pin in the chain. Figure 9 shows a complete error detection sequence. PCA9922_1 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 01 — 15 January 2009 10 of 26 xxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxx x x x xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxx xx xx xxxxx xxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxx xxxxxx xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxx x x xxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxx xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxx xxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxxx xxx NXP Semiconductors PCA9922_1 Product data sheet enter error detect command some number of optional clocks to clock in 1s for testing at least 8 clocks shift halted load fault command shift resumed exit error detect command CLK SDI SDO fault data fault data MSB previous serial data shifting out this must be min. 2 µs wide and 3 clocks minimum with output enable LOW OE LE fault_load fault_data[n-1:0] fault_load goes LOW on this edge of OE fault data 8 bits error_detect_mode 002aad208 Fig 9. Timing for a complete error detection sequence PCA9922 11 of 26 © NXP B.V. 2009. All rights reserved. Lower-case signal names are internal signals shown to aid understanding of timing. 8-channel constant current LED driver with output error detection Rev. 01 — 15 January 2009 shift_reg[n-1:0] PCA9922 NXP Semiconductors 8-channel constant current LED driver with output error detection 8. Application design-in information 5V C 10 µF 3.3 V to 5.5 V LED0 LED1 LED2 LED3 LED7 PCA9922 R_EXT CLK SDI LE VSS VDD to next stage SDO OE PWM OR BLANKING INPUT MICROCONTROLLER SDO from last stage 002aad312 Fig 10. Typical application VLED = 3 V ∼ 4 V + VCE − VDD scan R OE CPU CLK LE LED0 PCA9922 VO VI VO VI LED7 SDI R_EXT VSS SDO OE CLK LE LED0 PCA9922 LED7 SDI R_EXT VSS SDO 002aad504 Fig 11. The PCA9922 in a typical multi-device architecture PCA9922_1 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 01 — 15 January 2009 12 of 26 PCA9922 NXP Semiconductors 8-channel constant current LED driver with output error detection 9. Limiting values Table 6. Limiting values In accordance with the Absolute Maximum Rating System (IEC 60134). Symbol Parameter Conditions Min Max Unit VDD supply voltage −0.5 +6.0 V VO(LED) LED output voltage VO(SDO) output voltage on pin SDO −0.5 +6.0 V −0.5 +6.0 V VI input voltage −0.4 VDD + 0.4 V ISS ground supply current - 485 mA IO(LEDn) output current on pin LEDn - 60 mA fclk clock frequency - 25 MHz Tstg storage temperature −65 +150 °C Tj junction temperature −40 +125 °C Ptot total power dissipation DIP16 - 1.12 W TSSOP16 - 0.625 W HVQFN20 - 3.125 W pins LED0 to LED7 operating Tamb = 25 °C 10. Recommended operating conditions Table 7. Operating conditions Symbol Parameter VDD supply voltage Conditions VO(LED) LED output voltage Min Max Unit 3.3 5.5 V inactive - 5.5 V output active pins LED0 to LED7 - 2.2 V IO(LEDn) output current on pin LEDn 15 60 mA VO(SDO) output voltage on pin SDO - 5.5 V Ptot total power dissipation DIP16 - 0.44 W TSSOP16 - 0.25 W HVQFN20 - 1.25 W −40 +85 °C Toper Tamb = 85 °C operating temperature 11. Thermal characteristics Table 8. Thermal characteristics Symbol Parameter Conditions Typ Unit Rth(j-a) thermal resistance from junction to ambient DIP16 89 °C/W TSSOP16 160 °C/W HVQFN20 32 °C/W PCA9922_1 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 01 — 15 January 2009 13 of 26 PCA9922 NXP Semiconductors 8-channel constant current LED driver with output error detection 12. Static characteristics Table 9. Static characteristics VDD = 5.0 V; Tamb = 25 °C; unless otherwise specified. Symbol Parameter Conditions Min Typ Max Unit Vth(det)sc short-circuit detection threshold voltage for short-error detection; IO (target) = 5 mA to 120 mA 2.4 2.5 2.6 V Vth(norm) normal mode threshold voltage for short-error detection; IO (target) = 5 mA to 120 mA 2.3 - - V 0.7VDD - VDD + 0.3 V −0.3 - 0.3VDD V Control interface (OE, LE, CLK, SDI, SDO) [1] VIH HIGH-level input voltage VIL LOW-level input voltage VOL LOW-level output voltage IOL = 1 mA - - 0.4 V VOH HIGH-level output voltage IOL = −1 mA VDD − 0.4 - - V ILI input leakage current VI = VDD or VSS (CLK, SDI) −1 - +1 µA Ci input capacitance VI = VDD or 0 V - 1.5 5 pF RPU pull-up resistance OE pin 150 300 600 kΩ Rpd pull-down resistance LE pin 100 200 400 kΩ Current controlled outputs (LED[7:0]) IOL LOW-level output current VO = 0.7 V; Rext = 910 Ω 17.5 19.5 21.7 mA VO = 0.7 V; Rext = 470 Ω 35.4 38.1 40.8 mA ∆IOL LOW-level output current variation between bits VO = 0.7 V; Rext = 910 Ω - ±3.0 ±7 % VO = 0.7 V; Rext = 470 Ω - ±1.5 ±4 % Rext = open; LED[7:0] = off - 0.7 1.05 mA Rext = 910 Ω; LED[7:0] = off - 3.6 6.0 mA Rext = 470 Ω; LED[7:0] = off - 6.2 9.0 mA Rext = 910 Ω; LED[7:0] = on - 3.6 6.0 mA Rext = 470 Ω; LED[7:0] = on - 6.2 9.0 mA supply current IDD [1] OE must be held active LOW for at least the duration of the rise/fall time of the LEDn pins. This pulse width does not apply to active LOW times for executing error detect sequences. PCA9922_1 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 01 — 15 January 2009 14 of 26 PCA9922 NXP Semiconductors 8-channel constant current LED driver with output error detection 13. Dynamic characteristics Table 10. Dynamic characteristics Symbol tw(LE) Parameter LE pulse width tw(OE) OE pulse width Conditions VDD = 3.3 V Min Typ Max Unit [1] 10 - - ns [2] 200 - - ns tsu(SDI) SDI set-up time from SDI to CLK 5 - - ns th(SDI) SDI hold time from CLK to SDI 5 - - ns fCLK frequency on pin CLK 0 - 25 MHz δ clock duty cycle - 50 to 50 60 to 40 % tw(CLKH) CLK HIGH pulse width 16 - - ns tw(CLKL) CLK LOW pulse width 16 - - ns tPD(CLK-SDO) propagation delay from CLK to SDO - - 10 ns tsu(LE) LE set-up time from LE to CLK [3] 20 - - ns tsu(OE) OE set-up time from OE to CLK [3] 20 - - ns from CLK to LE [3] 5 - - ns [3] 5 - - ns th(LE) LE hold time th(OE) OE hold time from CLK to OE tPD(OE-LEDH) propagation delay from OE to LED HIGH pins LED0 to LED7; VDD = 5.0 V; CL = 30 pF; RL = 15 Ω; VL = 1.9 V; IO = 20.7 mA; Rext = 910 Ω - 210 - ns tPD(OE-LEDL) propagation delay from OE to LED LOW pins LED0 to LED7; VDD = 5.0 V; CL = 30 pF; RL = 15 Ω; VL = 1.9 V; IO = 20.7 mA; Rext = 910 Ω - 210 - ns tPD(LEH-LEDH) propagation delay from LE HIGH to LED HIGH pins LED0 to LED7; VDD = 5.0 V; CL = 30 pF; RL = 15 Ω; VL = 1.9 V; IO = 20.7 mA; Rext = 910 Ω; OE = logic 0 - 210 - ns tPD(LEH-LEDL) propagation delay from LE HIGH to LED LOW pins LED0 to LED7; VDD = 5.0 V; CL = 30 pF; RL = 15 Ω; VL = 1.9 V; IO = 20.7 mA; Rext = 910 Ω; OE = logic 0 - 210 - ns tPD(CLKH-LEDH) propagation delay pins LED0 to LED7; VDD = 5.0 V; from CLK HIGH to LED HIGH CL = 30 pF; RL = 15 Ω; VL = 1.9 V; IO = 20.7 mA; Rext = 910 Ω; OE = logic 0; LE = logic 1 - 210 - ns tPD(CLKH-LEDL) propagation delay pins LED0 to LED7; VDD = 5.0 V; from CLK HIGH to LED LOW CL = 30 pF; RL = 15 Ω; VL = 1.9 V; IO = 20.7 mA; Rext = 910 Ω; OE = logic 0; LE = logic 1 - 210 - ns tr rise time pins LED0 to LED7; VDD = 5.0 V; CL = 30 pF; RL = 15 Ω; VL = 1.9 V; IO = 20.7 mA; Rext = 910 Ω - 175 - ns tf fall time pins LED0 to LED7; VDD = 5.0 V; CL = 30 pF; RL = 15 Ω; VL = 1.9 V; IO = 20.7 mA; Rext = 910 Ω; OE = logic 0 - 190 - ns [1] Applies to normal device operation. This pulse width does not apply to active HIGH times for executing error detect sequences. PCA9922_1 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 01 — 15 January 2009 15 of 26 PCA9922 NXP Semiconductors 8-channel constant current LED driver with output error detection [2] OE must be held active LOW for at least the duration of the rise/fall time of the LEDn pins. This pulse width does not apply to active LOW times for executing error detect sequences. [3] Timing required for signaling of error detection sequences. Not necessary for ‘normal’ operation. fCLK tw(CLKH) CLK 50 % tsu(SDI) SDI 50 % th(OE) 50 % tsu(LE) LE th(SDI) 50 % tsu(OE) OE tw(CLKL) 50 % th(LE) 50 % 50 % tPD(CLK-SDO) SDO 50 % 002aad209 Fig 12. Timing 1 90 % LEDn 10 % tf 90 % 10 % tr 002aad210 Fig 13. LED[7:0] rise/fall timing PCA9922_1 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 01 — 15 January 2009 16 of 26 PCA9922 NXP Semiconductors 8-channel constant current LED driver with output error detection tw(OE) OE 50 % 50 % tPD(OE-LEDH) tPD(OE-LEDL) LEDn tPD(OE-LEDH) tPD(OE-LEDL) 50 % 50 % tw(LE) LE 50 % 50 % tPD(LEH-LEDH) tPD(LEH-LEDL) LEDn CLK 50 % 50 % 50 % tPD(CLKH-LEDH) tPD(CLKH-LEDL) LEDn 50 % 002aad211 Fig 14. Timing 2 PCA9922_1 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 01 — 15 January 2009 17 of 26 PCA9922 NXP Semiconductors 8-channel constant current LED driver with output error detection 14. Package outline DIP16: plastic dual in-line package; 16 leads (300 mil) SOT38-4 ME seating plane D A2 A A1 L c e Z w M b1 (e 1) b b2 MH 9 16 pin 1 index E 1 8 0 5 10 mm scale DIMENSIONS (inch dimensions are derived from the original mm dimensions) UNIT A max. A1 min. A2 max. b b1 b2 c D (1) E (1) e e1 L ME MH w Z (1) max. mm 4.2 0.51 3.2 1.73 1.30 0.53 0.38 1.25 0.85 0.36 0.23 19.50 18.55 6.48 6.20 2.54 7.62 3.60 3.05 8.25 7.80 10.0 8.3 0.254 0.76 inches 0.17 0.02 0.13 0.068 0.051 0.021 0.015 0.049 0.033 0.014 0.009 0.77 0.73 0.26 0.24 0.1 0.3 0.14 0.12 0.32 0.31 0.39 0.33 0.01 0.03 Note 1. Plastic or metal protrusions of 0.25 mm (0.01 inch) maximum per side are not included. OUTLINE VERSION REFERENCES IEC JEDEC JEITA EUROPEAN PROJECTION ISSUE DATE 95-01-14 03-02-13 SOT38-4 Fig 15. Package outline SOT38-4 (DIP16) PCA9922_1 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 01 — 15 January 2009 18 of 26 PCA9922 NXP Semiconductors 8-channel constant current LED driver with output error detection TSSOP16: plastic thin shrink small outline package; 16 leads; body width 4.4 mm SOT403-1 E D A X c y HE v M A Z 9 16 Q (A 3) A2 A A1 pin 1 index θ Lp L 1 8 e detail X w M bp 0 2.5 5 mm scale DIMENSIONS (mm are the original dimensions) UNIT A max. A1 A2 A3 bp c D (1) E (2) e HE L Lp Q v w y Z (1) θ mm 1.1 0.15 0.05 0.95 0.80 0.25 0.30 0.19 0.2 0.1 5.1 4.9 4.5 4.3 0.65 6.6 6.2 1 0.75 0.50 0.4 0.3 0.2 0.13 0.1 0.40 0.06 8 o 0 o Notes 1. Plastic or metal protrusions of 0.15 mm maximum per side are not included. 2. Plastic interlead protrusions of 0.25 mm maximum per side are not included. OUTLINE VERSION SOT403-1 REFERENCES IEC JEDEC JEITA EUROPEAN PROJECTION ISSUE DATE 99-12-27 03-02-18 MO-153 Fig 16. Package outline SOT403-1 (TSSOP16) PCA9922_1 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 01 — 15 January 2009 19 of 26 PCA9922 NXP Semiconductors 8-channel constant current LED driver with output error detection HVQFN20: plastic thermal enhanced very thin quad flat package; no leads; 20 terminals; body 5 x 5 x 0.85 mm A B D SOT662-1 terminal 1 index area A A1 E c detail X C e1 e b 6 y y1 C v M C A B w M C 10 L 11 5 e e2 Eh 1 15 terminal 1 index area 20 16 X Dh 0 2.5 5 mm scale DIMENSIONS (mm are the original dimensions) UNIT mm A(1) max. A1 b 1 0.05 0.00 0.38 0.23 c D(1) Dh E(1) Eh 0.2 5.1 4.9 3.25 2.95 5.1 4.9 3.25 2.95 e e1 2.6 0.65 e2 L v w y y1 2.6 0.75 0.50 0.1 0.05 0.05 0.1 Note 1. Plastic or metal protrusions of 0.075 mm maximum per side are not included. REFERENCES OUTLINE VERSION IEC JEDEC JEITA SOT662-1 --- MO-220 --- EUROPEAN PROJECTION ISSUE DATE 01-08-08 02-10-22 Fig 17. Package outline SOT662-1 (HVQFN20) PCA9922_1 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 01 — 15 January 2009 20 of 26 PCA9922 NXP Semiconductors 8-channel constant current LED driver with output error detection 15. Handling information All input and output pins are protected against ElectroStatic Discharge (ESD) under normal handling. When handling ensure that the appropriate precautions are taken as described in JESD625-A or equivalent standards. 16. Soldering of SMD packages This text provides a very brief insight into a complex technology. A more in-depth account of soldering ICs can be found in Application Note AN10365 “Surface mount reflow soldering description”. 16.1 Introduction to soldering Soldering is one of the most common methods through which packages are attached to Printed Circuit Boards (PCBs), to form electrical circuits. The soldered joint provides both the mechanical and the electrical connection. There is no single soldering method that is ideal for all IC packages. Wave soldering is often preferred when through-hole and Surface Mount Devices (SMDs) are mixed on one printed wiring board; however, it is not suitable for fine pitch SMDs. Reflow soldering is ideal for the small pitches and high densities that come with increased miniaturization. 16.2 Wave and reflow soldering Wave soldering is a joining technology in which the joints are made by solder coming from a standing wave of liquid solder. The wave soldering process is suitable for the following: • Through-hole components • Leaded or leadless SMDs, which are glued to the surface of the printed circuit board Not all SMDs can be wave soldered. Packages with solder balls, and some leadless packages which have solder lands underneath the body, cannot be wave soldered. Also, leaded SMDs with leads having a pitch smaller than ~0.6 mm cannot be wave soldered, due to an increased probability of bridging. The reflow soldering process involves applying solder paste to a board, followed by component placement and exposure to a temperature profile. Leaded packages, packages with solder balls, and leadless packages are all reflow solderable. Key characteristics in both wave and reflow soldering are: • • • • • • Board specifications, including the board finish, solder masks and vias Package footprints, including solder thieves and orientation The moisture sensitivity level of the packages Package placement Inspection and repair Lead-free soldering versus SnPb soldering 16.3 Wave soldering Key characteristics in wave soldering are: PCA9922_1 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 01 — 15 January 2009 21 of 26 PCA9922 NXP Semiconductors 8-channel constant current LED driver with output error detection • Process issues, such as application of adhesive and flux, clinching of leads, board transport, the solder wave parameters, and the time during which components are exposed to the wave • Solder bath specifications, including temperature and impurities 16.4 Reflow soldering Key characteristics in reflow soldering are: • Lead-free versus SnPb soldering; note that a lead-free reflow process usually leads to higher minimum peak temperatures (see Figure 18) than a SnPb process, thus reducing the process window • Solder paste printing issues including smearing, release, and adjusting the process window for a mix of large and small components on one board • Reflow temperature profile; this profile includes preheat, reflow (in which the board is heated to the peak temperature) and cooling down. It is imperative that the peak temperature is high enough for the solder to make reliable solder joints (a solder paste characteristic). In addition, the peak temperature must be low enough that the packages and/or boards are not damaged. The peak temperature of the package depends on package thickness and volume and is classified in accordance with Table 11 and 12 Table 11. SnPb eutectic process (from J-STD-020C) Package thickness (mm) Package reflow temperature (°C) Volume (mm3) < 350 ≥ 350 < 2.5 235 220 ≥ 2.5 220 220 Table 12. Lead-free process (from J-STD-020C) Package thickness (mm) Package reflow temperature (°C) Volume (mm3) < 350 350 to 2000 > 2000 < 1.6 260 260 260 1.6 to 2.5 260 250 245 > 2.5 250 245 245 Moisture sensitivity precautions, as indicated on the packing, must be respected at all times. Studies have shown that small packages reach higher temperatures during reflow soldering, see Figure 18. PCA9922_1 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 01 — 15 January 2009 22 of 26 PCA9922 NXP Semiconductors 8-channel constant current LED driver with output error detection maximum peak temperature = MSL limit, damage level temperature minimum peak temperature = minimum soldering temperature peak temperature time 001aac844 MSL: Moisture Sensitivity Level Fig 18. Temperature profiles for large and small components For further information on temperature profiles, refer to Application Note AN10365 “Surface mount reflow soldering description”. 17. Soldering of through-hole mount packages 17.1 Introduction to soldering through-hole mount packages This text gives a very brief insight into wave, dip and manual soldering. Wave soldering is the preferred method for mounting of through-hole mount IC packages on a printed-circuit board. 17.2 Soldering by dipping or by solder wave Driven by legislation and environmental forces the worldwide use of lead-free solder pastes is increasing. Typical dwell time of the leads in the wave ranges from 3 seconds to 4 seconds at 250 °C or 265 °C, depending on solder material applied, SnPb or Pb-free respectively. The total contact time of successive solder waves must not exceed 5 seconds. The device may be mounted up to the seating plane, but the temperature of the plastic body must not exceed the specified maximum storage temperature (Tstg(max)). If the printed-circuit board has been pre-heated, forced cooling may be necessary immediately after soldering to keep the temperature within the permissible limit. 17.3 Manual soldering Apply the soldering iron (24 V or less) to the lead(s) of the package, either below the seating plane or not more than 2 mm above it. If the temperature of the soldering iron bit is less than 300 °C it may remain in contact for up to 10 seconds. If the bit temperature is between 300 °C and 400 °C, contact may be up to 5 seconds. PCA9922_1 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 01 — 15 January 2009 23 of 26 PCA9922 NXP Semiconductors 8-channel constant current LED driver with output error detection 17.4 Package related soldering information Table 13. Suitability of through-hole mount IC packages for dipping and wave soldering Package Soldering method Dipping Wave CPGA, HCPGA - suitable DBS, DIP, HDIP, RDBS, SDIP, SIL suitable suitable[1] PMFP[2] - not suitable [1] For SDIP packages, the longitudinal axis must be parallel to the transport direction of the printed-circuit board. [2] For PMFP packages hot bar soldering or manual soldering is suitable. 18. Abbreviations Table 14. Abbreviations Acronym Description CDM Charged-Device Model EMI ElectroMagnetic Interference ESD ElectroStatic Discharge HBM Human Body Model LED Light Emitting Diode MM Machine Model MSB Most Significant Bit PCB Printed-Circuit Board PWM Pulse Width Modulator 19. Revision history Table 15. Revision history Document ID Release date Data sheet status Change notice Supersedes PCA9922_1 20090115 Product data sheet - - PCA9922_1 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 01 — 15 January 2009 24 of 26 PCA9922 NXP Semiconductors 8-channel constant current LED driver with output error detection 20. Legal information 20.1 Data sheet status Document status[1][2] Product status[3] Definition Objective [short] data sheet Development This document contains data from the objective specification for product development. Preliminary [short] data sheet Qualification This document contains data from the preliminary specification. Product [short] data sheet Production This document contains the product specification. [1] Please consult the most recently issued document before initiating or completing a design. [2] The term ‘short data sheet’ is explained in section “Definitions”. [3] The product status of device(s) described in this document may have changed since this document was published and may differ in case of multiple devices. The latest product status information is available on the Internet at URL http://www.nxp.com. 20.2 Definitions Draft — The document is a draft version only. The content is still under internal review and subject to formal approval, which may result in modifications or additions. NXP Semiconductors does not give any representations or warranties as to the accuracy or completeness of information included herein and shall have no liability for the consequences of use of such information. Short data sheet — A short data sheet is an extract from a full data sheet with the same product type number(s) and title. A short data sheet is intended for quick reference only and should not be relied upon to contain detailed and full information. For detailed and full information see the relevant full data sheet, which is available on request via the local NXP Semiconductors sales office. In case of any inconsistency or conflict with the short data sheet, the full data sheet shall prevail. 20.3 Disclaimers General — Information in this document is believed to be accurate and reliable. However, NXP Semiconductors does not give any representations or warranties, expressed or implied, as to the accuracy or completeness of such information and shall have no liability for the consequences of use of such information. Right to make changes — NXP Semiconductors reserves the right to make changes to information published in this document, including without limitation specifications and product descriptions, at any time and without notice. This document supersedes and replaces all information supplied prior to the publication hereof. Suitability for use — NXP Semiconductors products are not designed, authorized or warranted to be suitable for use in medical, military, aircraft, space or life support equipment, nor in applications where failure or malfunction of an NXP Semiconductors product can reasonably be expected to result in personal injury, death or severe property or environmental damage. NXP Semiconductors accepts no liability for inclusion and/or use of NXP Semiconductors products in such equipment or applications and therefore such inclusion and/or use is at the customer’s own risk. Applications — Applications that are described herein for any of these products are for illustrative purposes only. NXP Semiconductors makes no representation or warranty that such applications will be suitable for the specified use without further testing or modification. Limiting values — Stress above one or more limiting values (as defined in the Absolute Maximum Ratings System of IEC 60134) may cause permanent damage to the device. Limiting values are stress ratings only and operation of the device at these or any other conditions above those given in the Characteristics sections of this document is not implied. Exposure to limiting values for extended periods may affect device reliability. Terms and conditions of sale — NXP Semiconductors products are sold subject to the general terms and conditions of commercial sale, as published at http://www.nxp.com/profile/terms, including those pertaining to warranty, intellectual property rights infringement and limitation of liability, unless explicitly otherwise agreed to in writing by NXP Semiconductors. In case of any inconsistency or conflict between information in this document and such terms and conditions, the latter will prevail. No offer to sell or license — Nothing in this document may be interpreted or construed as an offer to sell products that is open for acceptance or the grant, conveyance or implication of any license under any copyrights, patents or other industrial or intellectual property rights. 20.4 Trademarks Notice: All referenced brands, product names, service names and trademarks are the property of their respective owners. 21. Contact information For more information, please visit: http://www.nxp.com For sales office addresses, please send an email to: [email protected] PCA9922_1 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 01 — 15 January 2009 25 of 26 PCA9922 NXP Semiconductors 8-channel constant current LED driver with output error detection 22. Contents 1 2 3 4 4.1 5 6 6.1 6.2 7 7.1 7.2 7.2.1 7.2.2 7.2.3 7.2.4 7.2.5 7.2.6 7.2.7 8 9 10 11 12 13 14 15 16 16.1 16.2 16.3 16.4 17 17.1 17.2 17.3 17.4 18 19 20 20.1 20.2 20.3 General description . . . . . . . . . . . . . . . . . . . . . . 1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Ordering information . . . . . . . . . . . . . . . . . . . . . 2 Ordering options . . . . . . . . . . . . . . . . . . . . . . . . 2 Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Pinning information . . . . . . . . . . . . . . . . . . . . . . 4 Pinning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Pin description . . . . . . . . . . . . . . . . . . . . . . . . . 5 Functional description . . . . . . . . . . . . . . . . . . . 6 System interface . . . . . . . . . . . . . . . . . . . . . . . . 6 LED output error detection . . . . . . . . . . . . . . . . 7 Open-circuit detection principle . . . . . . . . . . . . 7 Short-circuit detection principle . . . . . . . . . . . . 8 Entering error detect mode . . . . . . . . . . . . . . . . 8 Setting the outputs to test . . . . . . . . . . . . . . . . . 9 Capturing the fault/output error data. . . . . . . . . 9 Exit error detect mode . . . . . . . . . . . . . . . . . . 10 Error detection data . . . . . . . . . . . . . . . . . . . . 10 Application design-in information . . . . . . . . . 12 Limiting values. . . . . . . . . . . . . . . . . . . . . . . . . 13 Recommended operating conditions. . . . . . . 13 Thermal characteristics. . . . . . . . . . . . . . . . . . 13 Static characteristics. . . . . . . . . . . . . . . . . . . . 14 Dynamic characteristics . . . . . . . . . . . . . . . . . 15 Package outline . . . . . . . . . . . . . . . . . . . . . . . . 18 Handling information. . . . . . . . . . . . . . . . . . . . 21 Soldering of SMD packages . . . . . . . . . . . . . . 21 Introduction to soldering . . . . . . . . . . . . . . . . . 21 Wave and reflow soldering . . . . . . . . . . . . . . . 21 Wave soldering . . . . . . . . . . . . . . . . . . . . . . . . 21 Reflow soldering . . . . . . . . . . . . . . . . . . . . . . . 22 Soldering of through-hole mount packages . 23 Introduction to soldering through-hole mount packages . . . . . . . . . . . . . . . . . . . . . . . 23 Soldering by dipping or by solder wave . . . . . 23 Manual soldering . . . . . . . . . . . . . . . . . . . . . . 23 Package related soldering information . . . . . . 24 Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Revision history . . . . . . . . . . . . . . . . . . . . . . . . 24 Legal information. . . . . . . . . . . . . . . . . . . . . . . 25 Data sheet status . . . . . . . . . . . . . . . . . . . . . . 25 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Disclaimers . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 20.4 21 22 Trademarks . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Contact information . . . . . . . . . . . . . . . . . . . . 25 Contents. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Please be aware that important notices concerning this document and the product(s) described herein, have been included in section ‘Legal information’. © NXP B.V. 2009. All rights reserved. For more information, please visit: http://www.nxp.com For sales office addresses, please send an email to: [email protected] Date of release: 15 January 2009 Document identifier: PCA9922_1