PCF8576C Universal LCD driver for low multiplex rates Rev. 09 — 9 July 2009 Product data sheet 1. General description The PCF8576C is a peripheral device which interfaces to almost any Liquid Crystal Display (LCD)1 with low multiplex rates. It generates the drive signals for any static or multiplexed LCD containing up to four backplanes and up to 40 segments and can easily be cascaded for larger LCD applications. The PCF8576C is compatible with most microprocessors or microcontrollers and communicates via a two-line bidirectional I2C-bus. Communication overheads are minimized by a display RAM with auto-incremented addressing, by hardware subaddressing. 2. Features n Single-chip LCD controller and driver n 40 segment drives: u Up to twenty 7-segment numeric characters u Up to ten 14-segment alphanumeric characters u Any graphics of up to 160 elements n Versatile blinking modes n No external components required (even in multiple device applications) n Selectable backplane drive configuration: static or 2, 3, 4 backplane multiplexing n Selectable display bias configuration: static, 1⁄2 or 1⁄3 n Internal LCD bias generation with voltage-follower buffers n 40 × 4-bit RAM for display data storage n Auto-incremented display data loading across device subaddress boundaries n Display memory bank switching in static and duplex drive modes n Wide logic LCD supply range: u From 2 V for low-threshold LCDs u Up to 6 V for guest-host LCDs and high-threshold twisted nematic LCDs n Low power consumption n May be cascaded for large LCD applications (up to 2560 segments possible) n Cascadable with 24-segment LCD driver PCF8566 n No external components n Compatible with chip-on-glass technology n Separate or combined LCD and logic supplies n Optimized pinning for plane wiring in both and multiple PCF8576C applications n Power-saving mode for extremely low power consumption in battery-operated and telephone applications 1. The definition of the abbreviations and acronyms used in this data sheet can be found in Section 19. PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates 3. Ordering information Table 1. Ordering information Type number Package Name Description Version PCF8576CH LQFP64 plastic low profile quad flat package; 64 leads; body 10 × 10 × 1.4 mm SOT314-2 PCF8576CT VSO56 plastic very small outline package, 56 leads SOT190-1 PCF8576CTT HTSSOP56 plastic thermal enhanced thin shrink small outline package, 56 leads; SOT793-1 body width 6.1 mm; exposed die pad PCF8576CU/10 PCF8576CU/10 wire bond die; 56 bonding pads; 3.0 × 2.82 × 0.38 mm[1] PCF8576CU PCF8576CU/2 PCF8576CU/10 PCF8576CU wire bond die; 56 bonding pads; 3.0 × 2.82 × 0.38 mm[2] PCF8576CU PCF8576CU/2 bare die; 56 bumps; 3.0 × 2.82 × 0.40 PCF8576CU/2 [1] Delivery form: chip on FFC. [2] Delivery form: chip in tray. mm[2] 4. Marking Table 2. Marking codes Type number Marking code PCF8576CH PCF8576CH PCF8576CT PCF8576CT PCF8576CTT PCF8576CTT PCF8576CU/10 PC8576C-1 PCF8576CU PC8576C-1 PCF8576CU/2 PC8576C-2 PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 2 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates 5. Block diagram BP0 BP2 BP1 BP3 S0 to S39 40 VDD BACKPLANE OUTPUTS DISPLAY SEGMENT OUTPUTS LCD VOLTAGE SELECTOR DISPLAY LATCH LCD BIAS GENERATOR VLCD SHIFT REGISTER PCF8576C CLK TIMING INPUT BANK SELECTOR BLINKER SYNC DISPLAY RAM 40 × 4 BITS OUTPUT BANK SELECTOR DISPLAY CONTROLLER OSC OSCILLATOR POWERON RESET COMMAND DECODER VSS SCL SDA DATA POINTER INPUT FILTERS SUBADDRESS COUNTER I2C-BUS CONTROLLER SA0 A0 A1 A2 013aaa094 Fig 1. Block diagram of PCF8576C PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 3 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates 6. Pinning information 49 S18 50 S19 51 S20 52 S21 53 S22 54 S23 55 S24 56 S25 57 S26 58 S27 59 S28 60 S29 61 S30 62 S31 63 S32 64 S33 6.1 Pinning n.c. 1 48 n.c. S34 2 47 S17 S35 3 46 S16 S36 4 45 S15 S37 5 44 S14 S38 6 43 S13 S39 7 42 S12 n.c. 8 n.c. 9 41 S11 PCF8576CH 40 S10 SDA 10 39 S9 SCL 11 38 S8 SYNC 12 37 S7 13 36 S6 VDD 14 35 S5 OSC 15 34 S4 CLK A0 16 S3 32 S2 31 S1 30 S0 29 BP3 28 BP1 27 BP2 26 BP0 25 n.c. 24 n.c. 23 n.c. 22 VLCD 21 VSS 20 SA0 19 A2 18 A1 17 33 n.c. 001aag241 Top view. For mechanical details, see Figure 32. Fig 2. Pin configuration of PCF8576CH (LQFP64) PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 4 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates SDA 1 56 S39 SCL 2 55 S38 SYNC 3 54 S37 CLK 4 53 S36 VDD 5 52 S35 OSC 6 51 S34 A0 7 50 S33 A1 8 49 S32 A2 9 48 S31 SA0 10 47 S30 VSS 11 46 S29 VLCD 12 45 S28 BP0 13 44 S27 BP2 14 BP1 15 43 S26 PCF8576CT 42 S25 BP3 16 41 S24 S0 17 40 S23 S1 18 39 S22 S2 19 38 S21 S3 20 37 S20 S4 21 36 S19 S5 22 35 S18 S6 23 34 S17 S7 24 33 S16 S8 25 32 S15 S9 26 31 S14 S10 27 30 S13 S11 28 29 S12 001aag240 Top view. For mechanical details, see Figure 33. Fig 3. Pin configuration of PCF8576CT (VSO56) PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 5 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates SDA 1 56 S39 SCL 2 55 S38 SYNC 3 54 S37 CLK 4 53 S36 VDD 5 52 S35 OSC 6 51 S34 A0 7 50 S33 A1 8 49 S32 A2 9 48 S31 SA0 10 47 S30 VSS 11 46 S29 VLCD 12 45 S28 BP0 13 44 S27 BP2 14 BP1 15 43 S26 PCF8576CTT 42 S25 BP3 16 41 S24 S0 17 40 S23 S1 18 39 S22 S2 19 38 S21 S3 20 37 S20 S4 21 36 S19 S5 22 35 S18 S6 23 34 S17 S7 24 33 S16 S8 25 32 S15 S9 26 31 S14 S10 27 30 S13 S11 28 29 S12 013aaa095 Top view. For mechanical details, see Figure 34. Fig 4. Pin configuration of PCF8576CTT (HTSSOP56) PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 6 of 56 PCF8576C NXP Semiconductors S17 S16 S15 S14 S13 S12 S11 S10 S9 S8 S7 S6 S5 S4 Universal LCD driver for low multiplex rates 34 33 32 31 30 29 28 27 26 25 24 23 22 21 S18 35 20 S3 S19 36 19 S2 S20 37 18 S1 S21 38 17 S0 S22 39 16 BP3 S23 40 15 BP1 S24 41 S25 42 S26 43 S27 44 S28 45 S29 46 S30 47 11 VSS S31 48 10 SA0 S32 49 9 A2 S33 50 8 A1 14 BP2 PCF8576CU 13 BP0 51 52 53 54 55 56 1 2 3 4 5 6 7 S34 S35 S36 S37 S38 S39 SDA SCL SYNC CLK VDD OSC A0 12 VLCD 013aaa096 Top view. For mechanical details, see Figure 35, Figure 36 and Figure 37. Fig 5. Pin locations of PCF8576CU PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 7 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates 6.2 Pin description Table 3. Symbol Pin description Pin Description PCF8576CH PCF8576CT PCF8576CTT PCF8576CU SDA 10 1 1 I2C-bus serial data input and output SCL 11 2 2 I2C-bus serial clock input SYNC 12 3 3 cascade synchronization input and output CLK 13 4 4 external clock input/output supply voltage VDD 14 5 5[1] OSC 15 6 6 internal oscillator enable input A0 to A2 16 to 18 7 to 9 7 to 9 subaddress inputs SA0 19 10 10 I2C-bus address input; bit 0 VSS 20 11 11 logic ground VLCD 21 12 12 LCD supply voltage BP0, BP2, BP1, BP3 25 to 28 13 to 16 13 to 16 LCD backplane outputs S0 to S39 2 to 7, 29 to 32, 34 to 47, 49 to 64 17 to 56 17 to 56 LCD segment outputs n.c. 1, 8, 9, 22 to 24, 33, 48 - - not connected [1] The substrate (rear side of the die) is wired to VDD but should not be electrically connected. PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 8 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates 7. Functional description The PCF8576C is a versatile peripheral device designed to interface any microprocessor or microcontroller to a wide variety of LCDs. It can directly drive any static or multiplexed LCD containing up to 4 backplanes and up to 40 segments. The display configurations possible with the PCF8576C depend on the number of active backplane outputs required. Display configuration selection is shown in Table 4. All of the display configurations given in Table 4 can be implemented in the typical system shown in Figure 6. Table 4. Display configurations Number of: 7 segment numeric 14-segment numeric Backplanes Elements Digits Indicator symbols Characters Indicator symbols 4 160 20 20 10 20 160 (4 × 40) 3 120 15 15 8 8 120 (3 × 40) 2 80 10 10 5 10 80 (2 × 40) 1 40 5 5 2 12 40 (1 × 40) VDD R≤ tr 2CB V DD V LCD SDA HOST MICROPROCESSOR/ MICROCONTROLLER 40 segment drives SCL PCF8576C OSC 4 backplanes A0 A1 A2 Dot matrix SA0 V SS LCD PANEL (up to 160 elements) 013aaa098 VSS Fig 6. Typical system configuration The host microprocessor or microcontroller maintains the 2-line I2C-bus communication channel with the PCF8576C. Biasing voltages for the multiplexed LCD waveforms are generated internally, removing the need for an external bias generator. The internal oscillator is selected by connecting pin OSC to VSS. The only other connections required to complete the system are the power supplies (pins VDD, VSS and VLCD) and the LCD panel selected for the application. 7.1 Power-on-reset At power-on the PCF8576C resets to the following starting conditions: • • • • All backplane and segment outputs are set to VDD The selected drive mode is 1:4 multiplex with 1⁄3 bias Blinking is switched off Input and output bank selectors are reset (as defined in Table 8) PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 9 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates • The I2C-bus interface is initialized • The data pointer and the subaddress counter are cleared Remark: Do not transfer data on the I2C-bus for at least 1 ms after a power-on to allow the reset action to complete. 7.2 LCD bias generator The full-scale LCD voltage (Voper) is obtained from VDD − VLCD. The LCD voltage may be temperature compensated externally through the VLCD supply to pin VLCD. Fractional LCD biasing voltages are obtained from an internal voltage divider comprising three series resistors connected between VDD and VLCD. The center resistor can be switched out of the circuit to provide a 1⁄2 bias voltage level for the 1:2 multiplex configuration. 7.3 LCD voltage selector The LCD voltage selector coordinates the multiplexing of the LCD in accordance with the selected LCD drive configuration. The operation of the voltage selector is controlled by the mode-set command from the command decoder. The biasing configurations that apply to the preferred modes of operation, together with the biasing characteristics as functions of VLCD and the resulting discrimination ratios (D), are given in Table 5. Table 5. Preferred LCD drive modes: summary of characteristics LCD drive mode Number of: LCD bias V on ( RMS ) V off ( RMS ) V on ( RMS ) -------------------------- ------------------------- D = -------------------------V LCD V off ( RMS ) Backplanes Bias levels configuration V LCD static 1 2 static 0 1 ∞ 1:2 multiplex 2 3 1⁄ 2 0.354 0.791 2.236 1:2 multiplex 2 4 1⁄ 3 0.333 0.745 2.236 4 1⁄ 3 0.333 0.638 1.915 4 1⁄ 3 0.333 0.577 1.732 1:3 multiplex 3 1:4 multiplex 4 A practical value for VLCD is determined by equating Voff(RMS) with a defined LCD threshold voltage (Vth), typically when the LCD exhibits approximately 10 % contrast. In the static drive mode a suitable choice is VLCD < 3 × Vth. Multiplex drive modes of 1:3 and 1:4 with 1⁄2 bias are possible but the discrimination and hence the contrast ratios are smaller. 1 Bias is calculated by ------------- , where the values for a are 1+a a = 1 for 1⁄2 bias a = 2 for 1⁄3 bias The RMS on-state voltage (Von(RMS)) for the LCD is calculated with Equation 1 V on ( RMS ) = V LCD 1 (n – 1) 1 2 --- + ----------------- × ------------ 1 + a n n (1) where VLCD is the resultant voltage at the LCD segment and where the values for n are PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 10 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates n = 1 for static mode n = 2 for 1:2 multiplex n = 3 for 1:3 multiplex n = 4 for 1:4 multiplex The RMS off-state voltage (Voff(RMS)) for the LCD is calculated with Equation 2: V off ( RMS ) = V LCD a 2 – 2a + n -----------------------------2n × (1 + a) (2) Discrimination is the ratio of Von(RMS) to Voff(RMS) and is determined from Equation 3: V on ( RMS ) D = ----------------------- = V off ( RMS ) 2 (a + 1) + (n – 1) ------------------------------------------2 (a – 1) + (n – 1) (3) Using Equation 3, the discrimination for an LCD drive mode of 1:3 multiplex with 1⁄ 2 bias is 1⁄ 2 bias 21 is ---------- = 1.528 . 3 3 = 1.732 and the discrimination for an LCD drive mode of 1:4 multiplex with The advantage of these LCD drive modes is a reduction of the LCD full scale voltage VLCD as follows: • 1:3 multiplex (1⁄2 bias): V LCD = 6 × V off ( RMS ) = 2.449V off ( RMS ) 4 × 3) • 1:4 multiplex (1⁄2 bias): V LCD = (--------------------- = 2.309V off ( RMS ) 3 These compare with V LCD = 3V off ( RMS ) when 1⁄3 bias is used. It should be noted that VLCD is sometimes referred as the LCD operating voltage. PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 11 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates 7.4 LCD drive mode waveforms 7.4.1 Static drive mode The static LCD drive mode is used when a single backplane is provided in the LCD. Backplane and segment drive waveforms for this mode are shown in Figure 7. Tfr LCD segments VLCD BP0 VSS state 1 (on) VLCD state 2 (off) Sn VSS VLCD Sn+1 VSS (a) Waveforms at driver. VLCD state 1 0V −VLCD VLCD state 2 0V −VLCD (b) Resultant waveforms at LCD segment. mgl745 Vstate1(t) = VSn(t) − VBP0(t). Von(RMS) = VLCD. Vstate2(t) = VSn+1(t) − VBP0(t). Voff(RMS) = 0 V. Fig 7. Static drive mode waveforms PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 12 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates 7.4.2 1:2 Multiplex drive mode When two backplanes are provided in the LCD, the 1:2 multiplex mode applies. The PCF8576C allows the use of 1⁄2 bias or 1⁄3 bias (see Figure 8 and Figure 9). Tfr VLCD BP0 LCD segments VLCD / 2 VSS state 1 VLCD BP1 state 2 VLCD / 2 VSS VLCD Sn VSS VLCD Sn+1 VSS (a) Waveforms at driver. VLCD VLCD / 2 state 1 0V −VLCD / 2 −VLCD VLCD VLCD / 2 state 2 0V −VLCD / 2 −VLCD (b) Resultant waveforms at LCD segment. mgl746 Vstate1(t) = VSn(t) − VBP0(t). Von(RMS) = 0.791VLCD. Vstate2(t) = VSn(t) − VBP1(t). Voff(RMS) = 0.354VLCD Fig 8. Waveforms for the 1:2 multiplex drive mode with 1⁄2 bias PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 13 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates Tfr VLCD BP0 LCD segments 2VLCD / 3 VLCD / 3 VSS state 1 VLCD BP1 state 2 2VLCD / 3 VLCD / 3 VSS VLCD Sn Sn+1 2VLCD / 3 VLCD / 3 VSS VLCD 2VLCD / 3 VLCD / 3 VSS (a) Waveforms at driver. VLCD 2VLCD / 3 VLCD / 3 state 1 0V −VLCD / 3 −2VLCD / 3 −VLCD VLCD 2VLCD / 3 VLCD / 3 state 2 0V −VLCD / 3 −2VLCD / 3 −VLCD (b) Resultant waveforms at LCD segment. mgl747 Vstate1(t) = VSn(t) − VBP0(t). Von(RMS) = 0.745VLCD Vstate2(t) = VSn(t) − VBP1(t) Voff(RMS) = 0.333VLCD. Fig 9. Waveforms for the 1:2 multiplex drive mode with 1⁄3 bias PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 14 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates 7.4.3 1:3 Multiplex drive mode When three backplanes are provided in the LCD, the 1:3 multiplex drive mode applies as shown in Figure 10. Tfr VLCD BP0 LCD segments 2VLCD / 3 VLCD / 3 VSS state 1 VLCD BP1 BP2 state 2 2VLCD / 3 VLCD / 3 VSS VLCD 2VLCD / 3 VLCD / 3 VSS VLCD Sn 2VLCD / 3 VLCD / 3 VSS VLCD Sn+1 Sn+2 2VLCD / 3 VLCD / 3 VSS VLCD 2VLCD / 3 VLCD / 3 VSS (a) Waveforms at driver. VLCD 2VLCD / 3 VLCD / 3 state 1 0V −VLCD / 3 −2VLCD / 3 −VLCD VLCD 2VLCD / 3 VLCD / 3 state 2 0V −VLCD / 3 −2VLCD / 3 −VLCD (b) Resultant waveforms at LCD segment. mgl748 Vstate1(t) = VSn(t) − VBP0(t). Von(RMS) = 0.638VLCD. Vstate2(t) = VSn(t) − VBP1(t). Voff(RMS) = 0.333VLCD. Fig 10. Waveforms for the 1:3 multiplex drive mode with 1⁄3 bias PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 15 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates 7.4.4 1:4 multiplex drive mode When four backplanes are provided in the LCD, the 1:4 multiplex drive mode applies, as shown in Figure 11. Tfr VLCD BP0 LCD segments 2VLCD / 3 VLCD / 3 VSS state 1 VLCD BP1 state 2 2VLCD / 3 VLCD / 3 VSS VLCD BP2 2VLCD / 3 VLCD / 3 VSS VLCD BP3 2VLCD / 3 VLCD / 3 VSS VLCD Sn 2VLCD / 3 VLCD / 3 VSS VLCD Sn+1 2VLCD / 3 VLCD / 3 VSS VLCD Sn+2 2VLCD / 3 VLCD / 3 VSS VLCD Sn+3 2VLCD / 3 VLCD / 3 VSS (a) Waveforms at driver. VLCD 2VLCD / 3 VLCD / 3 state 1 0V −VLCD / 3 −2VLCD / 3 −VLCD VLCD 2VLCD / 3 VLCD / 3 state 2 0V −VLCD / 3 −2VLCD / 3 −VLCD (b) Resultant waveforms at LCD segment. mgl749 Vstate1(t) = VSn(t) − VBP0(t). Von(RMS) = 0.577VLCD. Vstate2(t) = VSn(t) − VBP1(t). Voff(RMS) = 0.333VLCD. Fig 11. Waveforms for the 1:4 multiplex mode with 1⁄3 bias PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 16 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates 7.5 Oscillator The internal logic and the LCD drive signals of the PCF8576C are timed by the frequency fclk, which equals either the built-in oscillator frequency fosc or the external clock frequency fclk(ext). The clock frequency (fclk) determines the LCD frame frequency (ffr) and the maximum rate for data reception from the I2C-bus. To allow I2C-bus transmissions at their maximum data rate of 100 kHz, fclk should be chosen to be above 125 kHz. 7.5.1 Internal clock The internal oscillator is enabled by connecting pin OSC to pin VSS. In this case, the output from pin CLK is the clock signal for any cascaded PCF8576s or PCF8566s in the system. Remark: The PCF8576C is backwards compatible with the PCF8576 (Voper up to 9 V). Where resistor Rext (on pin OSC) to VSS is present, the internal oscillator is selected. 7.5.2 External clock Connecting pin OSC to VDD enables an external clock source. Pin CLK then becomes the external clock input. Remark: A clock signal must always be supplied to the device. Removing the clock, freezes the LCD in a DC state, which is not suitable for the liquid crystal. 7.6 Timing The timing of the PCF8576C sequences the internal data flow of the device. This includes the transfer of display data from the display RAM to the display segment outputs. In cascaded applications, the synchronization signal (SYNC) maintains the correct timing relationship between the PCF8576Cs in the system. The timing also generates the LCD frame frequency which is derived as an integer division of the clock frequency (see Table 6). The frame frequency is set by the mode set commands when an internal clock is used or by the frequency applied to the pin CLK when an external clock is used. Table 6. LCD frame frequencies [1] PCF8576C mode Frame frequency Nominal frame frequency (Hz) Normal mode f clk f fr = -----------2880 69 [2] Power saving mode f clk f fr = --------480 65 [3] [1] The possible values for fclk see Table 20. [2] For fclk = 200 kHz. [3] For fclk = 31 kHz. The ratio between the clock frequency and the LCD frame frequency depends on the mode in which the device is operating. In the power-saving mode the reduction ratio is six times smaller; this allows the clock frequency to be reduced by a factor of six. The reduced clock frequency results in a significant reduction in power consumption. PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 17 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates The lower clock frequency has the disadvantage of increasing the response time when large amounts of display data are transmitted on the I2C-bus. When a device is unable to process a display data byte before the next one arrives, it holds the SCL line LOW until the first display data byte is stored. This slows down the transmission rate of the I2C-bus but no data loss occurs. 7.7 Display register The display register holds the display data while the corresponding multiplex signals are generated. There is a one-to-one relationship between the data in the display register, the LCD segment outputs and one column of the display RAM. 7.8 Shift register The shift register transfers display information from the display RAM to the display register while previous data is displayed. 7.9 Segment outputs The LCD drive section includes 40 segment outputs, S0 to S39, which must be connected directly to the LCD. The segment output signals are generated based on the multiplexed backplane signals and with data residing in the display register. When less than 40 segment outputs are required, the unused segment outputs should be left open-circuit. 7.10 Backplane outputs The LCD drive section includes four backplane outputs: BP0 to BP3. The backplane output signals are generated based on the selected LCD drive mode. • In 1:4 multiplex drive mode: BP0 to BP3 must be connected directly to the LCD. If less than four backplane outputs are required the unused outputs can be left as an open-circuit. • In 1:3 multiplex drive mode: BP3 carries the same signal as BP1, therefore these two adjacent outputs can be tied together to give enhanced drive capabilities. • In 1:2 multiplex drive mode: BP0 and BP2, BP1 and BP3 respectively carry the same signals and can also be paired to increase the drive capabilities. • In static drive mode: the same signal is carried by all four backplane outputs and they can be connected in parallel for very high drive requirements. 7.11 Display RAM The display RAM is a static 40 × 4-bit RAM which stores LCD data. A logic 1 in the RAM bitmap indicates the on-state of the corresponding LCD element; similarly, a logic 0 indicates the off-state. There is a direct relationship between the RAM addresses and the segment outputs, and between the individual bits of a RAM word and the backplane outputs. The display RAM bit map Figure 12 shows the rows 0 to 3 which correspond with the backplane outputs BP0 to BP3, and the columns 0 to 39 which correspond with the segment outputs S0 to S39. In multiplexed LCD applications the segment data of the first, second, third and fourth row of the display RAM are time-multiplexed with BP0, BP1, BP2 and BP3 respectively. PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 18 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates display RAM addresses (columns)/segment outputs (S) 0 1 2 3 4 35 36 37 38 39 0 display RAM bits 1 (rows)/ backplane outputs 2 (BP) 3 mbe525 Display RAM bit map showing direct relationship between RAM addresses and segment outputs; also between bits in a RAM word and the backplane outputs. Fig 12. Display RAM bit map When display data is transmitted to the PCF8576C, the display bytes received are stored in the display RAM in accordance with the selected LCD drive mode. The data is stored as it arrives and does not wait for an acknowledge cycle as with the commands. Depending on the current multiplex drive mode, data is stored singularly, in pairs, triplets or quadruplets. To illustrate the filling order, an example of a 7-segment numeric display showing all drive modes is given in Figure 13; the RAM filling organization depicted applies equally to other LCD types. The following applies to Figure 13: • In the static drive mode, the eight transmitted data bits are placed in row 0 of eight successive 4-bit RAM words. • In the 1:2 multiplex mode, the eight transmitted data bits are placed in pairs into row 0 and 1 of four successive 4-bit RAM words. • In the 1:3 multiplex mode, the eight bits are placed in triples into row 0, 1 and 2 to three successive 4-bit RAM words, with bit 3 of the third address left unchanged. It is not recommended to use this bit in a display because of the difficult addressing. This last bit may, if necessary, be controlled by an additional transfer to this address but care should be taken to avoid overwriting adjacent data because always full bytes are transmitted. • In the 1:4 multiplex mode, the eight transmitted data bits are placed in quadruples into row 0, 1, 2 and 3 of two successive 4-bit RAM words. PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 19 of 56 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 LCD segments LCD backplanes display RAM filling order NXP Semiconductors PCF8576C_9 Product data sheet drive mode transmitted display byte display RAM addresses (columns)/segment outputs (S) byte1 Sn+2 Sn+3 static a b f Sn+4 Sn+5 Sn+1 BP0 display RAM bits (rows)/ backplane outputs (BP) g e Sn+6 Sn Sn+7 c DP d 0 1 2 3 n n+1 n+2 n+3 n+4 n+5 n+6 n+7 c x x x b x x x a x x x f x x x g x x x e x x x d x x x DP x x x Sn Sn+1 b f g BP1 e c display RAM bits (rows)/ backplane outputs (BP) DP d Sn+1 Sn+2 f g e d DP b f multiplex BP1 c BP2 display RAM bits (rows)/ backplane outputs (BP) DP d n+1 n+2 n+3 a b x x f g x x e c x x d DP x x n Sn g e n MSB a b LSB f g e c d DP display RAM addresses (columns)/segment outputs (S) byte1 byte2 byte3 BP0 a 0 1 2 3 0 b 1 DP 2 c 3 x n+1 n+2 a d g x f e x x MSB LSB b DP c a d g f e display RAM addresses (columns)/segment outputs (S) byte1 byte2 byte3 byte4 byte5 a Sn 1:4 b f BP0 g multiplex 20 of 56 © NXP B.V. 2009. All rights reserved. Sn+1 BP1 c d DP BP3 display RAM bits (rows)/ backplane outputs (BP) 0 a 1 c 2 b 3 DP n+1 f e g d MSB a c b DP f LSB e g d 001aaj646 x = data bit unchanged. Fig 13. Relationship between LCD layout, drive mode, display RAM filling order and display data transmitted over the I2C-bus PCF8576C e n BP2 Universal LCD driver for low multiplex rates Rev. 09 — 9 July 2009 Sn+3 1:3 c b a a multiplex Sn+2 LSB display RAM addresses (columns)/segment outputs (S) byte1 byte2 BP0 1:2 MSB PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates 7.12 Data pointer The addressing mechanism for the display RAM is realized using the data pointer. This allows the loading of an individual display data byte or a series of display data bytes, into any location of the display RAM. The sequence commences with the initialization of the data pointer by the load data pointer command (see Table 13). After this, the data byte is stored starting at the display RAM address indicated by the data pointer (see Figure 13). Once each byte is stored, the data pointer is automatically incremented based on the selected LCD configuration. The contents of the data pointer are incremented as follows: • • • • In static drive mode by eight. In 1:2 multiplex drive mode by four. In 1:3 multiplex drive mode by three. In 1:4 multiplex drive mode by two. If an I2C-bus data access terminates early, the state of the data pointer is unknown. Consequently, the data pointer must be rewritten prior to further RAM accesses. 7.13 Sub-address counter The storage of display data is conditioned by the contents of the subaddress counter. Storage is allowed to take place only when the contents of the subaddress counter match with the hardware subaddress applied to A0, A1 and A2. The subaddress counter value is defined by the device select command (see Table 14). If the contents of the subaddress counter and the hardware subaddress do not match then data storage is blocked but the data pointer will be incremented as if data storage had taken place. The subaddress counter is also incremented when the data pointer overflows. The storage arrangements described lead to extremely efficient data loading in cascaded applications. When a series of display bytes are sent to the display RAM, automatic wrap-over to the next PCF8576C occurs when the last RAM address is exceeded. Subaddressing across device boundaries is successful even if the change to the next device in the cascade occurs within a transmitted character (such as during the 14th display data byte transmitted in 1:3 multiplex mode). 7.14 Bank selector 7.14.1 Output bank selector The output bank selector (see Table 15), selects one of the four bits per display RAM address for transfer to the display register. The actual bit selected depends on the LCD drive mode in operation and on the instant in the multiplex sequence. • In 1:4 multiplex mode: all RAM addresses of bit 0 are selected, followed sequentially by the contents of bit 1, bit 2 and then bit 3. • In 1:3 multiplex mode: bits 0, 1 and 2 are selected sequentially. • In 1:2 multiplex mode: bits 0 and 1 are selected. • In the static mode: bit 0 is selected. PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 21 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates The PCF8576C includes a RAM bank switching feature in the static and 1:2 multiplex drive modes. In the static drive mode, the bank select command may request the contents of bit 2 to be selected for display instead of the contents of bit 0. In 1:2 multiplex drive mode, the contents of bits 2 and 3 may be selected instead of bits 0 and 1. This enables preparation of display information in an alternative bank and the ability to switch to it once it has been assembled. 7.14.2 Input bank selector The input bank selector (see Table 15) loads display data into the display RAM based on the selected LCD drive configuration. Using the bank select command, display data can be loaded in bit 2 into static drive mode or in bits 2 and 3 into 1:2 multiplex drive mode. The input bank selector functions independently of the output bank selector. 7.15 Blinker The display blinking capabilities of the PCF8576C are very versatile. The whole display can be blinked at frequencies selected by the blink command. The blinking frequencies are integer fractions of the clock frequency; the ratios between the clock and blinking frequencies depend on the mode in which the device is operating (see Table 7). Table 7. Blink frequencies Blinking mode Normal operating mode ratio Power saving mode ratio Blink frequency off - - blinking off 1 f clk f blink = --------------92160 f clk f blink = --------------15360 2 Hz 2 f clk f blink = ------------------184320 f clk f blink = --------------30720 1 Hz 3 f clk f blink = ------------------368640 f clk f blink = --------------61440 0.5 Hz An additional feature is for an arbitrary selection of LCD segments to be blinked. This applies to the static and 1:2 multiplex drive modes and can be implemented without any communication overheads. Using the output bank selector, the displayed RAM banks are exchanged with alternate RAM banks at the blinking frequency. This mode can also be specified by the blink command (see Table 16). In the 1:3 and 1:4 multiplex modes, where no alternate RAM bank is available, groups of LCD segments can be blinked by selectively changing the display RAM data at fixed time intervals. If the entire display needs to be blinked at a frequency other than the nominal blink frequency, this can be done using the mode set command to set and reset the display enable bit E at the required rate (see Table 9). PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 22 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates 8. Basic architecture 8.1 Characteristics of the I2C-bus The I2C-bus provides bidirectional, two-line communication between different IC or modules. The two lines are a Serial Data line (SDA) and a Serial Clock Line (SCL). When connected to the output stages of a device, both lines must be connected to a positive supply via a pull-up resistor. Data transfer is initiated only when the bus is not busy. 8.1.1 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. Changes in the data line at this time will be interpreted as a control signal. Bit transfer is illustrated in Figure 14. SDA SCL data line stable; data valid change of data allowed mba607 Fig 14. Bit transfer 8.1.1.1 START and STOP conditions Both data and clock lines remain HIGH when the bus is not busy. A HIGH-to-LOW change of the data line, while the clock is HIGH, is defined as the START condition (S). A LOW-to-HIGH change of the data line, while the clock is HIGH, is defined as the STOP condition (P). The START and STOP conditions are illustrated in Figure 15. SDA SDA SCL SCL S P START condition STOP condition mbc622 Fig 15. Definition of START and STOP conditions 8.1.2 System configuration A device generating a message is a transmitter and a device receiving a message is the receiver. The device that controls the message is the master and the devices which are controlled by the master are the slaves. The system configuration is illustrated in Figure 16. PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 23 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates MASTER TRANSMITTER/ RECEIVER SLAVE TRANSMITTER/ RECEIVER SLAVE RECEIVER MASTER TRANSMITTER/ RECEIVER MASTER TRANSMITTER SDA SCL mga807 Fig 16. System configuration 8.1.3 Acknowledge The number of data bytes transferred between the START and STOP conditions from transmitter to receiver is unlimited. Each byte of eight bits is followed by an acknowledge bit. The acknowledge bit is a HIGH level signal put on the bus by the transmitter during which time the master generates an extra acknowledge related clock pulse. Acknowledgement on the I2C-bus is illustrated in Figure 17. • A slave receiver which is addressed must generate an acknowledge after the reception of each byte. • A master receiver must generate an acknowledge after the reception of each byte that has been clocked out of the slave transmitter. • The device that acknowledges must 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 consideration). • 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 master receiver must leave the data line HIGH during the 9th pulse to not acknowledge. The master will now generate a STOP condition. data output by transmitter not acknowledge data output by receiver acknowledge SCL from master 1 2 8 9 S START condition clock pulse for acknowledgement mbc602 Fig 17. Acknowledgement on the I2C-bus PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 24 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates 8.1.4 PCF8576C I2C-bus controller The PCF8576C acts as an I2C-bus slave receiver. It does not initiate I2C-bus transfers or transmit data to an I2C-bus master receiver. The only data output from the PCF8576C are the acknowledge signals of the selected devices. Device selection depends on the I2C-bus slave address, the transferred command data and the hardware subaddress. In single device application, the hardware subaddress inputs A0, A1 and A2 are normally tied to VSS which defines the hardware subaddress 0. In multiple device applications A0, A1 and A2 are tied to VSS or VDD using a binary coding scheme so that no two devices with a common I2C-bus slave address have the same hardware subaddress. In the power-saving mode it is possible that the PCF8576C is not able to keep up with the highest transmission rates when large amounts of display data are transmitted. If this situation occurs, the PCF8576C forces the SCL line LOW until its internal operations are completed. This is known as the clock synchronization feature of the I2C-bus and serves to slow down fast transmitters. Data loss does not occur. 8.1.5 Input filter To enhance noise immunity in electrically adverse environments, RC low-pass filters are provided on the SDA and SCL lines. 8.2 I2C-bus protocol Two I2C-bus slave addresses (0111000 and 0111001) are reserved for the PCF8576C. The least significant bit of the slave address that a PCF8576C responds to is defined by the level tied at its input SA0. Therefore, two types of PCF8576C can be distinguished on the same I2C-bus which allows: • Up to 16 PCF8576Cs on the same I2C-bus for very large LCD applications. • The use of two types of LCD multiplex on the same I2C-bus. The I2C-bus protocol is shown in Figure 18. The sequence is initiated with a START condition (S) from the I2C-bus master which is followed by one of the two PCF8576C slave addresses available. All PCF8576Cs with the corresponding SA0 level acknowledge in parallel with the slave address but all PCF8576Cs with the alternative SA0 level ignore the whole I2C-bus transfer. After acknowledgement, one or more command bytes (m) follow which define the status of the addressed PCF8576Cs. The last command byte is tagged with a cleared most significant bit, the continuation bit C. The command bytes are also acknowledged by all addressed PCF8576Cs on the bus. After the last command byte, a series of display data bytes (n) may follow. These display bytes are stored in the display RAM at the address specified by the data pointer and the subaddress counter. Both data pointer and subaddress counter are automatically updated and the data is directed to the intended PCF8576C device. The acknowledgement after each byte is made only by the (A0, A1 and A2) addressed PCF8576C. After the last display byte, the I2C-bus master issues a STOP condition (P). PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 25 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates acknowledge by A0, A1 and A2 selected PCF8576C only acknowledge by all addressed PCF8576Cs R/W slave address S S 0 1 1 1 0 0 A 0 A C 0 COMMAND A n ≥ 1 byte(s) 1 byte DISPLAY DATA A P n ≥ 0 byte(s) update data pointers and if necessary, subaddress counter mbe538 Fig 18. I2C-bus protocol 8.3 Command decoder The command decoder identifies command bytes that arrive on the I2C-bus. All available commands carry a continuation bit C in their most significant bit position as shown in Figure 19. When this bit is set, it indicates that the next byte of the transfer to arrive will also represent a command. If this bit is reset, it indicates that the command byte is the last in the transfer. Further bytes will be regarded as display data. The five commands available to the PCF8576C are defined in Table 8. MSB LSB C REST OF OPCODE msa833 (1) C = 0; last command (2) C = 1; commands continue Fig 19. General format of byte command Table 8. Command Definition of PCF8576C commands OPCODE Reference Description Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 mode set C 1 0 LP E B M1 M0 Section 8.3.1 defines LCD drive mode, LCD bias configuration, display status and power dissipation mode load data pointer C 0 P5 P4 P3 P2 P1 P0 Section 8.3.2 data pointer to define one of 40 display RAM addresses device select C 1 1 0 0 A2 A1 A0 Section 8.3.3 define one of eight hardware subaddresses bank select C 1 1 1 1 0 I O Section 8.3.4 bit I: defines input bank selection (storage of arriving display data); bit O: defines output bank selection (retrieval of LCD display data) blink C 1 1 1 0 A BF1 BF0 Section 8.3.5 defines the blink frequency and blink mode PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 26 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates 8.3.1 Mode set command Table 9. LCD drive mode command bit description LCD drive mode Drive mode Bit Backplane M1 M0 static BP0 0 1 1:2 BP0, BP1 1 0 1:3 BP0, BP1, BP2 1 1 1:4 BP0, BP1, BP2, BP3 0 0 Table 10. LCD bias configuration command bit description LCD bias Bit B 1⁄ 3 bias 0 1⁄ 2 bias 1 Table 11. Display status command bit description[1] Display status Bit E disabled (blank) 0 enabled 1 [1] The possibility to disable the display allows implementation of blinking under external control. Table 12. Power dissipation mode command bit description Display status Bit LP normal mode 0 power saving mode 1 8.3.2 Load data pointer command Table 13. Load data pointer command bit description Description Bits 6 bit binary value, 0 to 39 P5 P4 P3 P2 P1 P0 8.3.3 Device select command Table 14. Device select command bit description Description Bits 3 bit binary value, 0 to 7 A2 PCF8576C_9 Product data sheet A1 A0 © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 27 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates 8.3.4 Bank select command Table 15. Bank select command[1] Bank Mode Static 1:2 multiplex drive mode RAM bit 0 RAM bits 0 and 1 RAM bit 2 RAM bits 2 and 3 RAM bit 0 RAM bits 0 and 1 RAM bit 2 RAM bits 2 and 3 Bit Value I 0 Input bank 1 Output bank [1] O 0 1 The bank select command has no effect in 1:3 or 1:4 multiplex drive modes. 8.3.5 Blink command Table 16. Blink frequency command bit description Blink frequency Bit BF1 BF0 off 0 0 1 0 1 2 1 0 3 1 1 Table 17. Blink mode command bit description Blink mode Bit A normal blinking 0 alternate RAM bank blinking 1 8.4 Display controller The display controller executes the commands identified by the command decoder. It contains the status registers of the PCF8576C and coordinates their effects. The controller is also responsible for loading display data into the display RAM as required by the filling order. 9. Internal circuitry VLCD VSS SDA, SCL BP0 to BP3, S0 to S39 CLK, OSC, A0 to A2, SA0, SYNC VDD 013aaa109 Fig 20. Device protection diagram PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 28 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates 10. Limiting values CAUTION Static voltages across the liquid crystal display can build up when the LCD supply voltage (VLCD) is on while the IC supply voltage (VDD) is off, or vice versa. This may cause unwanted display artifacts. To avoid such artifacts, VLCD and VDD must be applied or removed together. Table 18. Limiting values In accordance with the Absolute Maximum Rating System (IEC 60134). Symbol Parameter Conditions VDD supply voltage VLCD LCD supply voltage VI input voltage on each of the pins SCL, SDA, CLK, SYNC, SA0, OSC and A0 to A2 VO output voltage on each of the pins S0 to S39 and BP0 to BP3 II Max −0.5 8.0 Unit V VDD − 8.0 VDD V −0.5 8.0 V −0.5 8.0 V input current −20 +20 mA IO output current −25 +25 mA IDD supply current −50 +50 mA ISS ground supply current −50 +50 mA IDD(LCD) LCD supply current −50 +50 mA Ptot total power dissipation - 400 mW Po output power - 100 mW Tstg storage temperature [2] −65 +150 °C electrostatic discharge voltage HBM [3] - ±4000 V MM [4] - ±200 V [5] - 100 mA VESD Ilu [1] latch-up current [1] [1] Values with respect to VDD. [2] According to the NXP store and transport conditions (document SNW-SQ-623) the devices have to be stored at a temperature of +5 °C to +45 °C and a humidity of 25 % to 75 %. [3] Pass level; Human Body Model (HBM) according to JESD22-A114. [4] Pass level; Machine Model (MM), according to JESD22-A115. [5] Pass level; latch-up testing, according to JESD78. PCF8576C_9 Product data sheet Min © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 29 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates 11. Static characteristics Table 19. Static characteristics VDD = 2.0 V to 6.0 V; VSS = 0 V; VLCD = VDD − 6.0 V; Tamb = −40 °C to +85 °C; unless otherwise specified. Symbol Parameter Conditions Min Typ Max Unit V Supplies VDD supply voltage VLCD LCD supply voltage 2.0 - 6.0 [1] VDD − 6.0 - VDD − 2.0 V IDD supply current: fclk = 200 kHz [2] - - 120 µA IDD(lp) low-power mode supply current VDD = 3.5 V; VLCD = 0 V; fclk = 35 kHz; A0, A1 and A2 connected to VSS - - 60 µA VIL LOW-level input voltage on pins CLK, SYNC, OSC, A0 to A2 and SA0 VSS - 0.3VDD V VIH HIGH-level input voltage on pins CLK, SYNC, OSC, A0 to A2 and SA0 0.7VDD - VDD V VOL LOW-level output voltage IOL = 0 mA - - 0.05 V VOH HIGH-level output voltage IOH = 0 mA VDD − 0.05 - - V IOL LOW-level output current VOL = 1.0 V; VDD = 5.0 V; on pins CLK and SYNC 1 - - mA IL leakage current VI = VDD or VSS; on pins CLK, SCL, SDA, A0 to A2 and SA0 −1 - +1 µA IL(OSC) leakage current on pin OSC VI = VDD −1 - +1 µA Ipd pull-down current VI = 1.0 V; VDD = 5.0 V; on pins A0 to A2 and OSC 15 50 150 µA RSYNC_N SYNC resistance 150 kΩ Logic VPOR power-on reset voltage [3] CI input capacitance [4] 20 50 - 1.0 1.6 V - - 7 pF VSS - 0.3VDD V I2C-bus; pins SDA and SCL VIL LOW-level input voltage VIH HIGH-level input voltage 0.7VDD - 6.0 V IOH(CLK) HIGH-level output current on pin CLK VOH = 4.0 V; VDD = 5.0 V −1 - - mA IOL(SDA) LOW-level output current on pin SDA VOL = 0.4 V; VDD = 5.0 V 3 - - mA −20 - +20 mV LCD outputs VBP voltage on pin BP Cbpl = 35 nF; on pins BP0 to BP3 VS voltage on pin S Csgm = 5 nF; on pins S0 to S39 RBP resistance on pin BP RS resistance on pin S −20 - +20 mV VLCD = VDD − 5 V; on pins BP0 to BP3 [5] - - 5 kΩ VLCD = VDD − 5 V; on pins S0 to S39 [5] - - 7.5 kΩ [1] VLCD ≤ VDD − 3 V for 1⁄3 bias. [2] LCD outputs are open-circuit; inputs at VSS or VDD; external clock with 50 % duty factor; I2C-bus inactive. [3] Resets all logic when VDD < VPOR. [4] Periodically sampled, not 100 % tested. [5] Outputs measured one at a time. PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 30 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates 11.1 Typical supply current characteristics mbe530 50 mbe529 50 −IDD(LCD) (µA) ISS (µA) normal mode 40 40 30 30 20 20 power-saving mode 10 10 0 0 0 100 200 0 100 ffr (Hz) 200 ffr (Hz) VDD = 5 V; VLCD = 0 V; Tamb = 25 °C VDD = 5 V; VLCD = 0 V; Tamb = 25 °C Fig 22. −IDD(LCD) as a function of ffr Fig 21. ISS as a function of ffr mbe528 50 mbe527 50 −IDD(LCD) (µA) ISS (µA) 40 40 normal mode fclk = 200 kHz 85 °C 30 30 20 20 −40 °C power-saving mode fclk = 35 kHz 10 25 °C 10 0 0 0 5 VDD (V) 0 10 VLCD = 0 V; external clock; Tamb = 25 °C Fig 23. ISS as a function of VDD VDD (V) 10 VLCD = 0 V; external clock; Tamb = 25 °C Fig 24. −IDD(LCD) as a function of VDD PCF8576C_9 Product data sheet 5 © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 31 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates 11.2 Typical LCD output characteristics mbe532 10 RO(max) (kΩ) mbe526 2.5 RO(max) (kΩ) RS 2.0 RS 1.5 RBP 1 RBP 1.0 0.5 10−1 0 3 VDD (V) 6 0 −40 VLCD = 0 V; Tamb = 25 °C Fig 25. RO(max) as a function of VDD 40 80 120 Tamb (°C) VDD = 5 V; VLCD = 0 V Fig 26. RO(max) as a function of Tamb PCF8576C_9 Product data sheet 0 © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 32 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates 12. Dynamic characteristics Table 20. Dynamic characteristics VDD = 1.8 V to 5.5 V; VSS = 0 V; VLCD = 2.5 V to 6.5 V; Tamb = −40 °C to +85 °C; unless otherwise specified. Symbol Parameter Conditions Min Typ Max Unit normal mode; VDD = 5 V 125 200 315 kHz 31 48 kHz Timing characteristics: driver timing waveforms (see Figure 27) [1] clock frequency fclk 21 power saving mode; VDD = 3 V tclk(H) clock HIGH time 1 - - µs tclk(L) clock LOW time 1 - - µs - - 400 ns 1 - - µs - - 30 µs tPD(SYNC_N) SYNC propagation delay tSYNC_NL SYNC LOW time tPD(drv) driver propagation delay VLCD = VDD − 5 V Timing characteristics: I2C-bus (see Figure 28) [2] tBUF bus free time between a STOP and START condition 4.7 - - µs tHD;STA hold time (repeated) START condition 4.0 - - µs tSU;STA set-up time for a repeated START condition 4.7 - - µs tLOW LOW period of the SCL clock 4.7 - - µs tHIGH HIGH period of the SCL clock 4.0 - - µs tr rise time of both SDA and SCL signals - - 1 µs tf fall time of both SDA and SCL signals - - 0.3 µs Cb capacitive load for each bus line - - 400 pF tSU;DAT data set-up time 250 - - ns tHD;DAT data hold time 0 - - ns tSU;STO set-up time for STOP condition 4.0 - - µs [1] fclk < 125 kHz, I2C-bus maximum transmission speed is derated. [2] All timing values are valid within the operating supply voltage and ambient temperature range and are referenced to VIL and VIH with an input voltage swing of VSS to VDD. PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 33 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates 1/fCLK tclk(H) tclk(L) 0.7VDD CLK 0.3VDD 0.7VDD SYNC 0.3VDD tPD(SYNC_N) tPD(SYNC_N) tSYNC_NL 0.5 V BP0 to BP3, and S0 to S39 (VDD = 5 V) 0.5 V tPD(drv) mce424 Fig 27. Driver timing waveforms SDA tBUF tLOW tf SCL tHD;STA tr tHD;DAT tHIGH tSU;DAT SDA tSU;STA tSU;STO mga728 Fig 28. I2C-bus timing waveforms PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 34 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates 13. Application information 13.1 Cascaded operation In large display configurations, up to 16 PCF8576Cs can be recognized on the same I2C-bus by using the 3-bit hardware subaddress (A0, A1 and A2) and the programmable I2C-bus slave address (SA0). Table 21. Addressing cascaded PCF8576C Cluster Bit SA0 Pin A2 Pin A1 Pin A0 Device 1 0 0 0 0 0 0 0 1 1 0 1 0 2 0 1 1 3 1 0 0 4 1 0 1 5 1 1 0 6 1 1 1 7 0 0 0 8 0 0 1 9 0 1 0 10 0 1 1 11 1 0 0 12 1 0 1 13 1 1 0 14 1 1 1 15 2 1 Cascaded PCF8576Cs are synchronized. They can share the backplane signals from one of the devices in the cascade. Such an arrangement is cost-effective in large LCD applications since the backplane outputs of only one device need to be through-plated to the backplane electrodes of the display. The other PCF8576Cs of the cascade contribute additional segment outputs but their backplane outputs are left open-circuit (see Figure 29). The PCF8576C can also be cascaded with the PCF8566. The connections are identical to the PCF8576C cascade. PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 35 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates VDD SDA 1 SCL 2 SYNC VLCD 5 12 17 to 56 40 segment drives LCD PANEL PCF8576CT 3 CLK 13,15, 14,16 4 OSC 6 A0 A1 A2 BP0 to BP3 (open-circuit) (up to 2560 elements) SAO VSS VLCD VDD R≤ tr 2CB VLCD VDD 5 HOST MICROPROCESSOR/ MICROCONTROLLER SDA SCL SYNC CLK OSC 12 1 17 to 56 2 40 segment drives PCF8576CT 3 13,15, 14,16 4 4 backplanes BP0 to BP3 6 mbe533 7 VSS A0 8 A1 9 A2 10 11 SA0 VSS Fig 29. Cascaded PCF8576C configuration The SYNC line is provided to maintain the correct synchronization between all cascaded PCF8576Cs. This synchronization is guaranteed after the power-on reset. The only time that SYNC is likely to be needed is if synchronization is accidentally lost (e.g. by noise in adverse electrical environments; or by the defining a multiplex mode when PCF8576Cs with differing SA0 levels are cascaded). SYNC is organized as an input/output pin; the output selection being realized as an open-drain driver with an internal pull-up resistor. A PCF8576C asserts the SYNC line and monitors the SYNC line at all other times. If synchronization in the cascade is lost, it is restored by the first PCF8576C to assert SYNC. The timing relationship between the backplane waveforms and the SYNC signal for the various drive modes of the PCF8576C are shown in Figure 30. For single plane wiring of packaged PCF8576Cs and chip-on-glass cascading, see Figure 31. . PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 36 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates Tfr = 1 ffr BP0 SYNC (a) static drive mode. BP0 (1/2 bias) BP0 (1/3 bias) SYNC (b) 1:2 multiplex drive mode. BP0 (1/3 bias) SYNC (c) 1:3 multiplex drive mode. BP0 (1/3 bias) SYNC (d) 1:4 multiplex drive mode. mgl755 Excessive capacitive coupling between SCL or CLK and SYNC will cause erroneous synchronization. If this is a problem you can increase the capacitance of the SYNC line (e.g. by an external capacitor between SYNC and VDD.) Degradation of the positive edge of the SYNC pulse can be countered by an external pull-up resistor. Fig 30. Synchronization of the cascade for the various PCF8576C drive modes PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 37 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates SDA SCL SYNC CLK VDD VSS VLCD SDA 1 56 S39 1 56 S79 SCL 2 55 S38 2 55 S78 SYNC 3 54 S37 3 54 S77 CLK 4 53 S36 4 53 S76 VDD 5 52 S35 5 52 S75 OSC 6 51 S34 6 51 S74 A0 7 50 S33 7 50 S73 A1 8 49 S32 8 49 S72 A2 9 48 S31 9 48 S71 SA0 10 47 S30 10 47 S70 VSS 11 46 S29 11 46 S69 VLCD 12 45 S28 12 45 S68 BP0 13 44 S27 BP0 13 44 S67 BP2 14 43 S26 BP2 14 43 S66 BP1 15 42 S25 BP1 15 42 S65 BP3 16 41 S24 BP3 16 41 S64 S0 17 40 S23 S40 17 40 S63 S1 18 39 S22 S41 18 39 S62 S2 19 38 S21 S42 19 38 S61 S3 20 S43 20 34 S17 34 S57 S7 24 33 S16 S47 24 33 S56 S8 25 32 S15 S48 25 32 S55 S9 26 31 S14 S49 26 31 S54 S10 27 30 S13 S50 27 30 S53 S11 28 29 S12 S51 28 29 S52 open PCF8576CT S0 S10 S11 S12 S13 S39 S40 segments backplanes S50 PCF8576CT S51 S52 S53 S79 mbe537 Fig 31. Single plane wiring of packaged PCF8576CTs PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 38 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates 14. Package outline LQFP64: plastic low profile quad flat package; 64 leads; body 10 x 10 x 1.4 mm SOT314-2 c y X A 48 33 49 32 ZE e E HE A A2 (A 3) A1 wM θ bp pin 1 index 64 Lp L 17 detail X 16 1 ZD e v M A wM bp D B HD v M B 0 2.5 5 mm scale DIMENSIONS (mm are the original dimensions) UNIT A max. A1 A2 A3 bp c D (1) E (1) e mm 1.6 0.20 0.05 1.45 1.35 0.25 0.27 0.17 0.18 0.12 10.1 9.9 10.1 9.9 0.5 HD HE 12.15 12.15 11.85 11.85 L Lp v w y 1 0.75 0.45 0.2 0.12 0.1 Z D (1) Z E (1) 1.45 1.05 1.45 1.05 θ 7o o 0 Note 1. Plastic or metal protrusions of 0.25 mm maximum per side are not included. REFERENCES OUTLINE VERSION IEC JEDEC SOT314-2 136E10 MS-026 JEITA EUROPEAN PROJECTION ISSUE DATE 00-01-19 03-02-25 Fig 32. Package outline SOT314-2 (LQFP64) of PCF8576CH PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 39 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates VSO56: plastic very small outline package; 56 leads SOT190-1 D E A X c y HE v M A Z 56 29 Q A2 A (A 3) A1 pin 1 index θ Lp L 1 detail X 28 w M bp e 0 5 10 mm scale DIMENSIONS (inch dimensions are derived from the original mm dimensions) UNIT A max. A1 A2 A3 bp c D (1) E (2) e HE L Lp Q v w y Z (1) mm 3.3 0.3 0.1 3.0 2.8 0.25 0.42 0.30 0.22 0.14 21.65 21.35 11.1 11.0 0.75 15.8 15.2 2.25 1.6 1.4 1.45 1.30 0.2 0.1 0.1 0.90 0.55 inches 0.13 0.012 0.004 0.12 0.11 0.01 0.017 0.0087 0.85 0.012 0.0055 0.84 0.44 0.62 0.0295 0.43 0.60 0.089 0.063 0.055 0.057 0.035 0.008 0.004 0.004 0.051 0.022 θ 7o o 0 Notes 1. Plastic or metal protrusions of 0.3 mm (0.012 inch) maximum per side are not included. 2. Plastic interlead protrusions of 0.25 mm (0.01 inch) maximum per side are not included. OUTLINE VERSION REFERENCES IEC JEDEC JEITA EUROPEAN PROJECTION ISSUE DATE 97-08-11 03-02-19 SOT190-1 Fig 33. Package outline SOT190-1 (VSO56) of PCF8576CT PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 40 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates HTSSOP56: plastic thermal enhanced thin shrink small outline package; 56 leads; body width 6.1 mm; exposed die pad D SOT793-1 A E X c y exposed die pad v M A HE Dh Z 56 29 (A 3) A A2 Eh θ A1 pin 1 index Lp L detail X 1 28 w M bp e 0 2.5 5 mm scale DIMENSIONS (mm are the original dimensions) UNIT A max. A1 A2 A3 bp c D (1) Dh E (2) Eh e HE L Lp v w y Z (1) θ mm 1.2 0.15 0.05 1.05 0.80 0.25 0.27 0.17 0.20 0.09 14.1 13.9 4.3 4.1 6.2 6.0 4.3 4.1 0.5 8.3 7.9 1 0.8 0.4 0.2 0.08 0.1 0.4 0.1 8o o 0 Notes 1. Plastic or metal protrusions of 0.15 mm maximum per side are not included. 2. Plastic or metal protrusions of 0.25 mm maximum per side are not included. REFERENCES OUTLINE VERSION IEC JEDEC SOT793-1 143E36T MO-153 JEITA EUROPEAN PROJECTION ISSUE DATE 03-03-04 Fig 34. Package outline SOT793-1 (HTSSOP56) of PCF8576CTT PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 41 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates 15. Bare die outline Wire bond die; 56 bonding pads; 3.0 x 2.82 x 0.38 mm PCF8576CU/10 D A 34 21 C1 20 35 e X x 0 E 0 y (4) 50 8 C2 51 56 1 7 F P4 P3 P2 P1 detail X 0 0.5 scale Dimensions Unit mm 1 mm A D E e(3) P1(1) P2(2) P3(1) P4(2) max 0.610 nom 0.38 2.82 3.00 0.110 0.097 0.110 0.097 min 0.096 Note 1. Pad size 2. Passivation opening 3. Dimension not drawn to scale 4. Marking code: PC8576C-1 Outline version pcf8576cu_10_do References IEC JEDEC JEITA PCF8576CU/10 European projection Issue date 09-06-02 Fig 35. Bare die outline of PCF8576CU/10 PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 42 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates Wire bond die; 56 bonding pads; 3.0 x 2.82 x 0.38 mm PCF8576CU D A 34 21 C1 20 35 e X x 0 E 0 y (4) 50 8 C2 51 56 1 7 F P4 P3 P2 P1 detail X 0 0.5 scale Dimensions Unit mm 1 mm A D E e(3) P1(1) P2(2) P3(1) P4(2) max 0.610 nom 0.38 2.82 3.00 0.110 0.097 0.110 0.097 min 0.096 Note 1. Pad size 2. Passivation opening 3. Dimension not drawn to scale 4. Marking code: PC8576C-1 Outline version pcf8576cu_do References IEC JEDEC JEITA PCF8576CU European projection Issue date 29-06-02 Fig 36. Bare die outline of PCF8576CU PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 43 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates Bare die; 56 bumps; 3.0 x 2.82 x 0.40 mm PCF8576CU/2 D 34 21 C1 20 35 e X x E 0 0 y (2) 50 8 C2 51 56 1 7 F Y L A A2 A1 b detail X detail Y 0 0.5 scale Dimensions Unit mm 1 mm A A1 A2 b max nom 0.398 0.0175 0.380 0.094 min D E e(1) L 0.610 2.82 3.00 0.094 0.096 Note 1. Dimension not drawn to scale 2. Marking code: PC8576C-2 Outline version pcf8576cu_2_do References IEC JEDEC JEITA PCF8576CU/2 European projection Issue date 09-06-02 Fig 37. Bare die outline of PCF8576CU/2 PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 44 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates Table 22. Pad and bump description for PCF8576CU All x/y coordinates represent the position of the center of each pad with respect to the center (x/y = 0) of the chip. Symbol Pad X (µm) Y (µm) Description SDA 1 −74 −1380 I2C-bus serial data input/output SCL 2 148 −1380 I2C-bus serial clock input SYNC 3 355 −1380 cascade synchronization input/output CLK 4 534 −1380 external clock input/output VDD 5 742 −1380 supply voltage OSC 6 913 −1380 internal oscillator enable input A0 7 1087 −1380 subaddress input A1 8 1290 −1284 subaddress input A2 9 1290 −1116 subaddress input SA0 10 1290 −945 subaddress input VSS 11 1290 −751 logic ground VLCD 12 1290 −485 LCD supply voltage BP0 13 1290 125 LCD backplane output BP2 14 1290 285 LCD backplane output BP1 15 1290 458 LCD backplane output BP3 16 1290 618 LCD backplane output S0 17 1290 791 LCD segment output S1 18 1290 951 LCD segment output S2 19 1290 1124 LCD segment output S3 20 1290 1284 LCD segment output S4 21 1074 1380 LCD segment output S5 22 914 1380 LCD segment output S6 23 741 1380 LCD segment output S7 24 581 1380 LCD segment output S8 25 408 1380 LCD segment output S9 26 248 1380 LCD segment output S10 27 75 1380 LCD segment output S11 28 −85 1380 LCD segment output S12 29 −258 1380 LCD segment output S13 30 −418 1380 LCD segment output S14 31 −591 1380 LCD segment output S15 32 −751 1380 LCD segment output S16 33 −924 1380 LCD segment output S17 34 −1084 1380 LCD segment output S18 35 −1290 1243 LCD segment output S19 36 −1290 1083 LCD segment output S20 37 −1290 910 LCD segment output S21 38 −1290 750 LCD segment output S22 39 −1290 577 LCD segment output PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 45 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates Table 22. Pad and bump description for PCF8576CU All x/y coordinates represent the position of the center of each pad with respect to the center (x/y = 0) of the chip. Symbol Pad X (µm) Y (µm) Description S23 40 −1290 417 LCD segment output S24 41 −1290 244 LCD segment output S25 42 −1290 84 LCD segment output S26 43 −1290 −89 LCD segment output S27 44 −1290 −249 LCD segment output S28 45 −1290 −422 LCD segment output S29 46 −1290 −582 LCD segment output S30 47 −1290 −755 LCD segment output S31 48 −1290 −915 LCD segment output S32 49 −1290 −1088 LCD segment output S33 50 −1290 −1248 LCD segment output S34 51 −1083 −1380 LCD segment output S35 52 −923 −1380 LCD segment output S36 53 −750 −1380 LCD segment output S37 54 −590 −1380 LCD segment output S38 55 −417 −1380 LCD segment output S39 56 −257 −1380 LCD segment output Table 23. Alignment marks Symbol X (µm) Y (µm) C1 −1290 1385 C2 −1295 −1385 F 1305 −1405 16. Handling information All input and output pins are protected against ElectroStatic Discharge (ESD) under normal handling. When handling Metal-Oxide Semiconductor (MOS) devices ensure that all normal precautions are taken as described in JESD625-A, IEC 61340-5 or equivalent standards. 17. Packing information 17.1 Tray information Tray information for the PCF8576CU and PCF8576CU/2 is shown in Figure 38, Figure 39 and Table 24. PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 46 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates G A C H D B F E 001aai237 marking code Fig 38. Tray details 001aaj619 Fig 39. Tray alignment Table 24. Tray dimensions Symbol Description Value A pocket pitch; x direction 5.59 mm B pocket pitch; y direction 6.35 mm C pocket width; x direction 3.22 mm D pocket width; y direction 3.50 mm PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 47 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates Table 24. Tray dimensions Symbol Description Value E tray width; x direction 50.67 mm F tray width; y direction 50.67 mm G cut corner to pocket 1,1 center 5.78 mm H cut corner to pocket 1,1 center 6.29 mm J tray thickness 3.94 mm K tray cross section 1.76 mm L tray cross section 2.46 mm M pocket depth 0.89 mm x number of pockets; x direction 8 y number of pockets; y direction 7 PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 48 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates 17.2 Film frame carrier information 100 m S aw lane 200 m detail X Marking code Straight edge of the wafer X 013aaa112 Fig 40. Layout of wafer on film frame carrier of PCF8576CU/10 PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 49 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates 18. 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”. 18.1 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. 18.2 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 18.3 Wave soldering Key characteristics in wave soldering are: • 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 PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 50 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates 18.4 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 41) 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 25 and 26 Table 25. 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 26. 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 41. PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 51 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates temperature maximum peak temperature = MSL limit, damage level minimum peak temperature = minimum soldering temperature peak temperature time 001aac844 MSL: Moisture Sensitivity Level Fig 41. Temperature profiles for large and small components For further information on temperature profiles, refer to Application Note AN10365 “Surface mount reflow soldering description”. PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 52 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates 19. Abbreviations Table 27. Abbreviations Acronym Description DC Direct Current FFC Film Frame Carrier HBM Human Body Model I2C Inter-Integrated Circuit IC Integrated Circuit LCD Liquid Crystal Display LSB Least Significant Bit MM Machine Model MOS Metal Oxide Semiconductor MSB Most Significant Bit MSL Moisture Sensitivity Level PCB Printed-Circuit Board POR Power-On Reset RC Resistance-Capacitance RAM Random Access Memory RMS Root Mean Square SCL Serial Clock Line SDA Serial Data Line SMD Surface Mount Device PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 53 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates 20. Revision history Table 28. Revision history Document ID Release date Data sheet status Change notice Supersedes PCF8576C_9 20090709 Product data sheet - PCF8576C_8 Modifications: • The format of this data sheet has been redesigned to comply with the new identity guidelines of NXP Semiconductors. • • • • • • • Legal texts have been adapted to the new company name where appropriate. Symbols updated and checked with NXP Symbols Library Changed values in limiting values table (see Table 18) from relative to absolute values Added TT type Added bare die outline drawings Added FFC information Rewritten chapter 7.3 (see Section 7.3) PCF8576C_8 20041122 Product specification - PCF8576C_7 PCF8576C_7 20011002 Product specification - PCF8576C_6 PCF8576C_6 19980730 Product specification - PCF8576C_5 PCF8576C_5 19971114 Product specification - PCF8576C_4 PCF8576C_4 19970402 Product specification - PCF8576C_3 PCF8576C_3 19970203 Product specification - PCF8576C_2 PCF8576C_2 19961209 Product specification - PCF8576C_1 PCF8576C_1 19950630 Product specification - - PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 54 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates 21. Legal information 21.1 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. 21.2 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. 21.3 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. Bare die — All die are tested on compliance with their related technical specifications as stated in this data sheet up to the point of wafer sawing and are handled in accordance with the NXP Semiconductors storage and transportation conditions. If there are data sheet limits not guaranteed, these will be separately indicated in the data sheet. There are no post-packing tests performed on individual die or wafers. NXP Semiconductors has no control of third party procedures in the sawing, handling, packing or assembly of the die. Accordingly, NXP Semiconductors assumes no liability for device functionality or performance of the die or systems after third party sawing, handling, packing or assembly of the die. It is the responsibility of the customer to test and qualify their application in which the die is used. All die sales are conditioned upon and subject to the customer entering into a written die sale agreement with NXP Semiconductors through its legal department. Export control — This document as well as the item(s) described herein may be subject to export control regulations. Export might require a prior authorization from national authorities. 21.4 Trademarks Notice: All referenced brands, product names, service names and trademarks are the property of their respective owners. I2C-bus — logo is a trademark of NXP B.V. 22. Contact information For more information, please visit: http://www.nxp.com For sales office addresses, please send an email to: [email protected] PCF8576C_9 Product data sheet © NXP B.V. 2009. All rights reserved. Rev. 09 — 9 July 2009 55 of 56 PCF8576C NXP Semiconductors Universal LCD driver for low multiplex rates 23. Contents 1 2 3 4 5 6 6.1 6.2 7 7.1 7.2 7.3 7.4 7.4.1 7.4.2 7.4.3 7.4.4 7.5 7.5.1 7.5.2 7.6 7.7 7.8 7.9 7.10 7.11 7.12 7.13 7.14 7.14.1 7.14.2 7.15 8 8.1 8.1.1 8.1.1.1 8.1.2 8.1.3 8.1.4 8.1.5 8.2 8.3 8.3.1 8.3.2 8.3.3 8.3.4 General description . . . . . . . . . . . . . . . . . . . . . . 1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Ordering information . . . . . . . . . . . . . . . . . . . . . 2 Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Pinning information . . . . . . . . . . . . . . . . . . . . . . 4 Pinning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Pin description . . . . . . . . . . . . . . . . . . . . . . . . . 8 Functional description . . . . . . . . . . . . . . . . . . . 9 Power-on-reset . . . . . . . . . . . . . . . . . . . . . . . . . 9 LCD bias generator. . . . . . . . . . . . . . . . . . . . . 10 LCD voltage selector . . . . . . . . . . . . . . . . . . . 10 LCD drive mode waveforms . . . . . . . . . . . . . . 12 Static drive mode . . . . . . . . . . . . . . . . . . . . . . 12 1:2 Multiplex drive mode . . . . . . . . . . . . . . . . . 13 1:3 Multiplex drive mode . . . . . . . . . . . . . . . . . 15 1:4 multiplex drive mode . . . . . . . . . . . . . . . . . 16 Oscillator. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Internal clock. . . . . . . . . . . . . . . . . . . . . . . . . . 17 External clock . . . . . . . . . . . . . . . . . . . . . . . . . 17 Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Display register . . . . . . . . . . . . . . . . . . . . . . . . 18 Shift register . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Segment outputs. . . . . . . . . . . . . . . . . . . . . . . 18 Backplane outputs . . . . . . . . . . . . . . . . . . . . . 18 Display RAM . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Data pointer . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Sub-address counter . . . . . . . . . . . . . . . . . . . 21 Bank selector . . . . . . . . . . . . . . . . . . . . . . . . . 21 Output bank selector. . . . . . . . . . . . . . . . . . . . 21 Input bank selector . . . . . . . . . . . . . . . . . . . . . 22 Blinker. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Basic architecture . . . . . . . . . . . . . . . . . . . . . . 23 Characteristics of the I2C-bus . . . . . . . . . . . . . 23 Bit transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 START and STOP conditions . . . . . . . . . . . . . 23 System configuration . . . . . . . . . . . . . . . . . . . 23 Acknowledge . . . . . . . . . . . . . . . . . . . . . . . . . 24 PCF8576C I2C-bus controller . . . . . . . . . . . . . 25 Input filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 I2C-bus protocol . . . . . . . . . . . . . . . . . . . . . . . 25 Command decoder . . . . . . . . . . . . . . . . . . . . . 26 Mode set command . . . . . . . . . . . . . . . . . . . . 27 Load data pointer command . . . . . . . . . . . . . . 27 Device select command . . . . . . . . . . . . . . . . . 27 Bank select command . . . . . . . . . . . . . . . . . . 28 8.3.5 8.4 9 10 11 11.1 11.2 12 13 13.1 14 15 16 17 17.1 17.2 18 18.1 18.2 18.3 18.4 19 20 21 21.1 21.2 21.3 21.4 22 23 Blink command. . . . . . . . . . . . . . . . . . . . . . . . Display controller . . . . . . . . . . . . . . . . . . . . . . Internal circuitry . . . . . . . . . . . . . . . . . . . . . . . Limiting values . . . . . . . . . . . . . . . . . . . . . . . . Static characteristics . . . . . . . . . . . . . . . . . . . Typical supply current characteristics. . . . . . . Typical LCD output characteristics . . . . . . . . . Dynamic characteristics . . . . . . . . . . . . . . . . . Application information . . . . . . . . . . . . . . . . . Cascaded operation . . . . . . . . . . . . . . . . . . . . Package outline . . . . . . . . . . . . . . . . . . . . . . . . Bare die outline . . . . . . . . . . . . . . . . . . . . . . . . Handling information . . . . . . . . . . . . . . . . . . . Packing information . . . . . . . . . . . . . . . . . . . . Tray information . . . . . . . . . . . . . . . . . . . . . . . Film frame carrier information . . . . . . . . . . . . Soldering of SMD packages . . . . . . . . . . . . . . Introduction to soldering. . . . . . . . . . . . . . . . . Wave and reflow soldering . . . . . . . . . . . . . . . Wave soldering. . . . . . . . . . . . . . . . . . . . . . . . Reflow soldering. . . . . . . . . . . . . . . . . . . . . . . Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . Revision history . . . . . . . . . . . . . . . . . . . . . . . Legal information . . . . . . . . . . . . . . . . . . . . . . Data sheet status . . . . . . . . . . . . . . . . . . . . . . Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . Disclaimers. . . . . . . . . . . . . . . . . . . . . . . . . . . Trademarks . . . . . . . . . . . . . . . . . . . . . . . . . . Contact information . . . . . . . . . . . . . . . . . . . . Contents. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 28 28 29 30 31 32 33 35 35 39 42 46 46 46 49 50 50 50 50 51 53 54 55 55 55 55 55 55 56 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: 9 July 2009 Document identifier: PCF8576C_9