ICM7211AM ® Data Sheet November 16, 2004 FN3158.5 4-Digit, LCD Display Driver Features The ICM7211AM device is a non-multiplexed four-digit seven-segment CMOS LCD display decoder-driver. • Four Digit Non-Multiplexed 7 Segment LCD Display Outputs with Backplane Driver This device is configured to drive conventional LCD displays by providing a complete RC oscillator, divider chain, backplane driver, and 28 segment outputs. • Complete Onboard RC Oscillator to Generate Backplane Frequency It also has a microprocessor compatible input configuration, which provides data input latches and Digit Address latches under control of high-speed Chip Select inputs. These devices simplify the task of implementing a cost-effective alphanumeric seven-segment display for microprocessor systems, without requiring extensive ROM or CPU time for decoding and display updating. • Backplane Input/Output Allows Simple Synchronization of Slave-Devices to a Master • Provides Data and Digit Address Latches Controlled by Chip Select Inputs to Provide a Direct High Speed Processor Interface • Decodes Binary to Code B (0-9, Dash, E, H, L, P, Blank) The ICM7211AM provides the “Code B” output code, i.e., 0-9, dash, E, H, L, P, blank, but will correctly decode true BCD to seven-segment decimal outputs. Ordering Information PART NUMBER ICM7211AMlPL DISPLAY TYPE LCD DISPLAY DECODING Code B 1 INPUT INTERFACING Microprocessor DISPLAY DRIVE TYPE Direct Drive TEMP. RANGE (°C) -40 to 85 PACKAGE 40 Ld PDIP PKG. DWG. # E40.6 CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures. 1-888-INTERSIL or 321-724-7143 | Intersil (and design) is a registered trademark of Intersil Americas Inc. Copyright Intersil Americas Inc. 2001, 2004. All Rights Reserved All other trademarks mentioned are the property of their respective owners. ICM7211AM Pinout ICM7211AM (PDIP) TOP VIEW VDD 1 40 d1 e1 2 39 c1 g1 3 38 b1 f1 4 37 a1 BP 5 36 OSC a2 6 35 VSS b2 7 34 CHIP SELECT 2 c2 8 33 CHIP SELECT 1 d2 9 32 DIGIT ADRESS BIT 2 e2 10 31 DIGIT ADRESS BIT 1 g2 11 30 B3 f2 12 29 B2 a3 13 28 B1 b3 14 27 B0 c3 15 26 f4 d3 16 25 g4 e3 17 24 e4 g3 18 23 d4 f3 19 22 c4 a4 20 21 b4 Functional Block Diagram DATA INPUTS 2-BIT DIGIT ADRESS INPUT CHIP SELECT 1 CHIP SELECT 2 DATA INPUTS ICM7211AM D4 SEGMENT OUTPUTS D3 SEGMENT OUTPUTS D2 SEGMENT OUTPUTS D1 SEGMENT OUTPUTS 7 WIDE DRIVER 7 WIDE DRIVER 7 WIDE DRIVER 7 WIDE DRIVER 7 WIDE LATCH EN 7 WIDE LATCH EN 7 WIDE LATCH EN 7 WIDE LATCH EN PROGRAMMABLE 4 TO 7 DECODER PROGRAMMABLE 4 TO 7 DECODER PROGRAMMABLE 4 TO 7 DECODER PROGRAMMABLE 4 TO 7 DECODER 4-BIT LATCH ENABLE 2-BIT LATCH 2 TO 4 DECODER ENABLE ONE SHOT OSCILLATOR 19kHz FREE-RUNNING OSCILLATOR INPUT ÷128 BLACKPLANE DRIVER ENABLE BP INPUT/OUTPUT ENABLE DIRECTOR 2 FN3158.5 November 16, 2004 ICM7211AM Absolute Maximum Ratings Thermal Information Supply Voltage (VDD - VSS) . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.5V Input Voltage (Any Terminal) (Note 1) . . . VSS - 0.3V to VDD , + 0.3V Thermal Resistance (Typical, Note 2) θJA (°C/W) PDIP Package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60 Maximum Junction Temperature . . . . . . . . . . . . . . . . . . . . . . . 150°C Maximum Storage Temperature Range . . . . . . . . .-65×°C to 150°C Maximum Lead Temperature (Soldering, 10s) . . . . . . . . . . . . 300°C Operating Conditions Temperature Range. . . . . . . . . . . . . . . . . . . . . . . . . . .-40°C to 85°C CAUTION: Stresses above those listed in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress only rating and operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied. NOTES: 1. Due to the SCR structure inherent in the CMOS process, connecting any terminal to voltages greater than VDD or less than VSS may cause destructive device latchup. For this reason, it is recommended that no inputs from external sources not operating on the same power supply be applied to the device before its supply is established, and that in multiple supply systems, the supply to the ICM7211AM be turned on first. 2. θJA is measured with the component mounted on an evaluation PC board in free air. Electrical Specifications PARAMETER TEST CONDITIONS MIN TYP MAX UNITS 3 5 6 V CHARACTERISTICS VDD = 5V ±10%, TA = 25°C, VSS = 0V Unless Otherwise Specified Operating Supply Voltage Range (VDD - VSS), VSUPPLY Operating Current, IDD Test circuit, Display blank - 10 50 µA Oscillator Input Current, IOSCI Pin 36 - ±2 ±10 µA Segment Rise/Fall Time, tr, tf CL = 200pF - 0.5 - µs Backplane Rise/Fall Time, tr, tf CL = 5000pF - 1.5 - µs Oscillator Frequency, fOSC Pin 36 Floating - 19 - kHz Backplane Frequency, fBP Pin 36 Floating - 150 - Hz Logical “1” Input Voltage, VIH 4 - - V Logical “0” Input Voltage, VIL - - 1 V ±0.01 ±1 µA INPUT CHARACTERISTICS Input Leakage Current, IILK Pins 27-34 - Input Capacitance, ClN Pins 27-34 - 5 BP/Brightness Input Leakage, IBPLK Measured at Pin 5 with Pin 36 at VSS - ±0.01 ±1 µA BP/Brightness Input Capacitance, CBPI All Devices - 200 - pF 200 - - ns Data Setup Time, tDS 100 - - ns Data Hold Time, tDH 10 0 - ns Inter-Chip Select Time, tICS 2 - - µs pF AC CHARACTERISTICS Chip Select Active Pulse Width, tWL Other Chip Select Either Held Active, or Both Driven Together Input Definitions In this table, VDD and VSS are considered to be normal operating input logic levels. Actual input low and high levels are specified under Operating Characteristics. For lowest power consumption, input signals should swing over the full supply. INPUT DIP TERMINAL CONDITIONS FUNCTION B0 27 VDD = Logical One VSS = Logical Zero Ones (Least Significant) B1 28 VDD = Logical One VSS = Logical Zero Twos B2 29 VDD = Logical One VSS = Logical Zero Fours B3 30 VDD = Logical One VSS = Logical Zero Eights (Most Significant) 3 Data Input Bits FN3158.5 November 16, 2004 ICM7211AM Input Definitions In this table, VDD and VSS are considered to be normal operating input logic levels. Actual input low and high levels are specified under Operating Characteristics. For lowest power consumption, input signals should swing over the full supply. (Continued) INPUT DIP TERMINAL OSC 36 CONDITIONS FUNCTION Floating or with External Capacitor to VDD Oscillator Input VSS Disables BP output devices, allowing segments to be synchronized to an external signal input at the BP terminal (Pin 5). Interface Input Configuration INPUT DESCRIPTION DIP TERMINAL CONDITIONS DA1 Digit Address Bit 1 (LSB) 31 VDD = Logical One VSS = Logical Zero DA2 Digit Address Bit 2 (MSB) 32 VDD = Logical One VSS = Logical Zero CS1 Chip Select 1 33 VDD = Inactive VSS = Active CS2 Chip Select 2 34 VDD = Inactive VSS = Active FUNCTION DA1 and DA2 serve as a 2-bit Digit Address Input DA2, DA1 = 00 selects D4 DA2, DA1 = 01 selects D3 DA2, DA1 = 10 selects D2 DA2, DA1 = 11 selects D1 When both CS1 and CS2 are taken low, the data at the Data and Digit Select code inputs are written into the input latches. On the rising edge of either Chip Select, the data is decoded and written into the output latches. Timing Diagram CS1 (CS2) tICS tWI CS2 (CS1) tDH tDS DATA AND DIGIT ADDRESS = DON’T CARE FIGURE 1. MICROPROCESSOR INTERFACE INPUT Typical Performance Curves 180 30 TA = 25°C DISPLAY BLANK, PIN 36 OPEN 150 25 COSC = 0pF (PIN 36 OPEN) TA = -20°C 120 TA = 25°C ƒBP (Hz) IOP (µA) 20 15 COSC = 22pF 90 60 10 TA = 70°C COSC = 220pF 30 5 0 1 2 3 4 5 6 7 VSUPP (V) FIGURE 2. OPERATING SUPPLY CURRENT AS A FUNCTION OF SUPPLY VOLTAGE 4 1 2 3 4 VSUPP (V) 5 6 FIGURE 3. BACKPLANE FREQUENCY AS A FUNCTION OF SUPPLY VOLTAGE FN3158.5 November 16, 2004 ICM7211AM Description Of Operation Device The ICM7211AM provides outputs suitable for driving conventional four-digit, seven-segment LCD displays. These devices include 28 individual segment drivers, backplane driver, and a self-contained oscillator and divider chain to generate the backplane frequency. The segment and backplane drivers each consist of a CMOS inverter, with the N-Channel and P-Channel devices ratioed to provide identical on resistances, and thus equal rise and fall times. This eliminates any DC component, which could arise from differing rise and fall times, and ensures maximum display life. The backplane output devices can be disabled by connecting the OSCillator input (pin 36) to VSS . This allows the 28 segment outputs to be synchronized directly to a signal input at the BP terminal (pin 5). In this manner, several slave devices may be cascaded to the backplane output of one master device, or the backplane may be derived from an external source. This allows the use of displays with characters in multiples of four and a single backplane. A slave device represents a load of approximately 200pF (comparable to one additional segment). Thus the limitation of the number of devices that can be slaved to one master device backplane driver is the additional load represented by the larger backplane of displays of more than four digits. A good rule of thumb to observe in order to minimize power consumption is to keep the backplane rise and fall times less than about 5µs. The backplane output driver should handle the backplane to a display of 16 one-half inch characters. It is recommended, if more than four devices are to be slaved together, the backplane signal be derived externally and all the ICM7211AM devices be slaved to it. This external signal should be capable of driving very large capacitive loads with short (1 - 2µs) rise and fall times. The maximum frequency for a backplane signal should be about 150Hz although this may be too fast for optimum display response at lower display temperatures, depending on the display type. The onboard oscillator is designed to free run at approximately 19kHz at microampere current levels. The oscillator frequency is divided by 128 to provide the backplane frequency, which will be approximately 150Hz with the oscillator free-running; the oscillator frequency may be reduced by connecting an external capacitor between the OSCillator terminal and VDD . The oscillator may also be overdriven if desired, although care must be taken to ensure that the backplane driver is not disabled during the negative portion of the overdriving signal (which could cause a DC component to the display). This can be done by driving the OSCillator input between the positive supply and a level out of the range where the backplane disable is sensed (about one fifth of the supply voltage above VSS). 5 Another technique for overdriving the oscillator (with a signal swinging the full supply) is to skew the duty cycle of the overdriving signal such that the negative portion has a duration shorter than about one microsecond. The backplane disable sensing circuit will not respond to signals of this duration. OSCILLATOR FREQUENCY 128 CYCLES BACKPLANE INPUT/OUTPUT 64 CYCLES 64 CYCLES OFF SEGMENTS ON SEGMENTS FIGURE 4. DISPLAY WAVEFORMS Input Configurations and Output Codes The ICM7211AM accepts a four-bit true binary (i.e., positive level = logical one) input at pins 27 thru 30, least significant bit at pin 27 ascending to the most significant bit at pin 30. It decodes the binary input into seven-segment alphanumeric “Code B” output, i.e., 0-9, dash, E, H, L, P, blank. These codes are shown explicitly in Table 1. It will correctly decode true BCD to a seven-segment decimal output. TABLE 1. OUTPUT CODES BlNARY B3 B2 B1 BO 0 0 0 0 0 0 0 1 0 0 1 0 0 0 1 1 0 1 0 0 0 1 0 1 0 1 1 0 0 1 1 1 1 0 0 0 1 0 0 1 1 0 1 0 1 0 1 1 CODE B ICM7211AM FN3158.5 November 16, 2004 ICM7211AM pin 34) are taken low. On the rising edge of either chip select input, the content of the data input latches is decoded and stored in the output latches of the digit selected by the contents of the digit address latches. TABLE 1. OUTPUT CODES (Continued) BlNARY B3 B2 B1 BO 1 1 0 0 1 1 0 1 1 1 1 0 1 1 1 1 CODE B ICM7211AM An address of 00 writes into D4, DA2 = 0, DA1 = 1 writes into D3, DA2 = 1, DA1 = 0 writes into D2, and 11 writes into D1. The timing relationships for inputting data are shown in Figure 1, and the chip select pulse widths and data setup and hold times are specified under Operating Characteristics. BLANK a f b g The ICM7211AM is intended to accept data from a data bus under processor control. e c d In these devices, the four data input bits and the two-bit digit address (DA1 pin 31, DA2 pin 32) are written into input buffer latches when both chip select inputs (CS1 pin 33, CS2 FIGURE 5. SEGMENT ASSIGNMENT Test Circuit VDD + VSS - 1 VDD 2 40 ICM7211AM 38 4 37 5 BP OSC 36 6 VSS 35 34 7 8 EACH SEGMENT OUTPUT TO BACKPLANE WITH A 200pF CAPACITOR 39 3 9 10 DIGIT/CHIP SELECT INPUTS 13 VDD MICROPROCESSOR VERSION VSS MULTIPLEXED VERSION 32 31 30 11 12 33 DATA INPUTS 29 28 14 27 15 26 16 25 17 24 18 23 19 22 20 21 VDD FIGURE 6. 6 FN3158.5 November 16, 2004 ICM7211AM Typical Application 8 DIGIT LCD DISPLAY ICM7211AM HIGH ORDER DIGITS +5V 20 P10 27 VSS 28 29 2 XTAL1 30 31 32 3 XTAL2 33 4 RESET P17 34 P20 21 7 EA 22 23 24 35 5 SS 80C48 36 µCOMPUTER 37 P27 38 1 TO DB0 12 13 39 T1 14 15 6 INT 16 17 18 DB7 19 40 26 VCC VDD NC INPUT ALE PSEN PROG WR 11 9 25 10 +5V 1 VDD 2, 3, 4 SEGMENTS 6-26 35 VSS 37-40 DATA 36 OSC B0-B3 I/O ICM7211AM LOW ORDER DIGITS BP 5 DS1 DS2 CS1 CS2 27 28 29 30 31 32 33 34 BP 5 DATA B0-B3 2, 3, 4 1 VDD 6-26 SEGMENTS 35 VSS 37-40 36 OSC +5V DS1 DS2 CS1 CS2 27 28 29 30 31 32 33 34 I/O RD 8 FIGURE 7. 80C48 MICROPROCESSOR INTERFACE All Intersil U.S. products are manufactured, assembled and tested utilizing ISO9000 quality systems. Intersil Corporation’s quality certifications can be viewed at www.intersil.com/design/quality Intersil products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time without notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be accurate and reliable. However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries. For information regarding Intersil Corporation and its products, see www.intersil.com 7 FN3158.5 November 16, 2004