ICM7228 ® Data Sheet December 6, 2005 8-Digit, Microprocessor-Compatible, LED Display Decoder Driver FN3160.8 Features • Pb-Free Plus Anneal Available (RoHS Compliant) The Intersil ICM7228 display driver interfaces microprocessors to an 8-digit, 7-segment, numeric LED display. Included on chip are two types of 7-segment decoder, multiplex scan circuitry, LED display segment drivers, LED display digit drivers and an 8-byte static memory as display RAM. • Improved 2nd Source to Maxim ICM7218 • Fast Write Access Time of 200ns • Multiple Microprocessor Compatible Versions • Hexadecimal, Code B and No Decode Modes Data can be written to the ICM7228A and ICM7228B’s display RAM in sequential 8-digit update or in single-digit update format. Data is written to the ICM7228C display RAM in parallel random access format. The ICM7228A and ICM7228C drive common anode displays. The ICM7228B drives common cathode displays. All versions can display the RAM data as either Hexadecimal or Code B format. The ICM7228A and ICM7228B incorporate a No Decode mode allowing each bit of each digit's RAM word to drive individual display segments resulting in independent control of all display segments. As a result, bargraph and other irregular display segments and formats can be driven directly by this chip. The Intersil ICM7228 is an alternative to both the Maxim ICM7218 and the Intersil ICM7218 display drivers. Notice that the ICM7228A/B has an additional single digit access mode. This could make the Intersil ICM7218A/B software incompatible with ICM7228A/B operation. • Individual Segment Control with “No Decode” Feature • Digit and Segment Drivers On-Chip • Non-Overlapping Digits Drive • Common Anode and Common Cathode LED Versions • Low Power CMOS Architecture • Single 5V Supply Applications • Instrumentation • Test Equipment • Hand Held Instruments • Bargraph Displays • Numeric and Non-Numeric Panel Displays • High and Low Temperature Environments where LCD Display Integrity is Compromised Ordering Information PART NUMBER PART MARKING DATA ENTRY PROTOCOL DISPLAY TYPE TEMP. RANGE (oC) PACKAGE PKG. DWG. # ICM7228AIBI ICM7228AIBI Sequential Common Anode -40 to 85 28 Ld SOIC M28.3 ICM7228AIBIZ (Note) 7228AIBIZ Sequential Common Anode -40 to 85 28 Ld SOIC (Pb-free) M28.3 ICM7228AIPI ICM7228AIPI Sequential Common Anode -40 to 85 28 Ld PDIP E28.6 ICM7228AIPIZ (Note) ICM7228AIPI Sequential Common Anode -40 to 85 28 Ld PDIP* (Pb-free) E28.6 ICM7228BIBI ICM7228BIBI Sequential Common Cathode -40 to 85 28 Ld SOlC M28.3 ICM7228BIBIZ (Note) ICM7228BIBIZ Sequential Common Cathode -40 to 85 28 Ld SOlC (Pb-free) M28.3 ICM7228BIPI ICM7228BIPI Sequential Common Cathode -40 to 85 28 Ld PDIP E28.6 ICM7228BIPIZ (Note) ICM7228BIPIZ Sequential Common Cathode -40 to 85 28 Ld PDIP (Pb-free) E28.6 ICM7228CIBI ICM7228CIBI Random Common Anode -40 to 85 28 Ld SOlC M28.3 ICM7228CIBIZ (Note) ICM7228CIBIZ Random Common Anode -40 to 85 28 Ld SOlC (Pb-free) M28.3 ICM7228CIPI ICM7228CIPI Random Common Anode -40 to 85 28 Ld PDIP E28.6 ICM7228CIPIZ (Note) ICM7228CIPI Random Common Anode -40 to 85 28 Ld PDIP (Pb-free) E28.6 *Pb-free PDIPs can be used for through hole wave solder processing only. They are not intended for use in Reflow solder processing applications. NOTE: Intersil Pb-free plus anneal products employ special Pb-free material sets; molding compounds/die attach materials and 100% matte tin plate termination finish, which are RoHS compliant and compatible with both SnPb and Pb-free soldering operations. Intersil Pb-free products are MSL classified at Pb-free peak reflow temperatures that meet or exceed the Pb-free requirements of IPC/JEDEC J STD-020. 1 CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures. 1-888-INTERSIL or 1-888-468-3774 | Intersil (and design) is a registered trademark of Intersil Americas Inc. Copyright © Intersil Americas Inc. 2002-2005. All Rights Reserved All other trademarks mentioned are the property of their respective owners. ICM7228 Pinouts ICM7228B (PDIP, SOIC) COMMON CATHODE TOP VIEW ICM7228A (PDIP, SOIC) COMMON ANODE TOP VIEW SEG c 1 28 VSS DIGIT 4 1 28 VSS SEG e 2 27 SEG a DIGIT 6 2 27 DIGIT 7 SEG b 3 26 SEG g DIGIT 3 3 26 DIGIT 5 DP 4 25 SEG d DIGIT 1 4 25 DIGIT 2 ID6 (HEXA/CODE B) 5 24 SEG f ID6 (HEXA/CODE B) 5 24 DIGIT 8 ID5 (DECODE) 6 23 DIGIT 3 ID5 (DECODE) 6 23 SEG g ID7 (DATA COMING) 7 22 DIGIT 6 ID7 (DATA COMING) 7 22 SEG f WRITE 8 21 DIGIT 7 WRITE 8 21 SEG e MODE 9 20 DIGIT 4 MODE 9 20 SEG c 19 VDD ID4 (SHUTDOWN) 10 ID4 (SHUTDOWN) 10 19 VDD ID1 11 18 DIGIT 8 ID1 11 18 SEG d ID0 12 17 DIGIT 5 ID0 12 17 SEG b ID2 13 16 DIGIT 2 ID2 13 16 SEG a ID3 14 15 DIGIT 1 ID3 14 15 DP ICM7228C (PDIP, SOIC) COMMON ANODE TOP VIEW SEG c 1 28 VSS SEG e 2 27 SEG a SEG b 3 26 SEG g DP 4 25 SEG d DA0 (DIGIT ADDRESS 0) 5 24 SEG f DA1 (DIGIT ADDRESS 1) 6 23 DIGIT 3 ID7 (INPUT DP) 7 22 DIGIT 6 WRITE 8 21 DIGIT 7 HEXA/CODE B/SHUTDOWN 9 20 DIGIT 4 19 VDD DA2 (DIGIT ADDRESS 2) 10 ID1 11 18 DIGIT 8 ID0 12 17 DIGIT 5 ID2 13 16 DIGIT 2 ID3 14 15 DIGIT 1 2 ICM7228 Functional Block Diagram ICM7228A, ICM7228B ID0 - ID7 INPUT DATA 8 8 ICM7228C ID4 - ID7 CONTROL INPUTS MODE 1 4 DA0 - DA2 ID0 - ID3 ID7 DIGIT DATA INPUT WRITE ADDRESS 5 1 3 HEXADECIMAL/ CODE B/ SHUTDOWN WRITE 1 1 DECODE SHUTDOWN CONTROL LOGIC HEXA/CODE B 1 1 1 8 8-BYTE STATIC RAM 8 1 SHUTDOWN 1 WRITE ADDRESS COUNTER 8 8-BYTE STATIC RAM 1 THREE LEVEL INPUT LOGIC 1 WRITE ADDRESS COUNTER 8 7 8 4 HEXADECIMAL/ CODE B DECODER READ ADDRESS, DIGIT MULTIPLEXER READ ADDRESS MULTIPLEXER 8 4 3 5 7 MULTIPLEX OSCILLATOR 7 1 HEXADECIMAL/ CODE B DECODER MULTIPLEX OSCILLATOR 1 DECODE NO-DECODE 8 7 1 8 INTERDIGIT BLANKING DECIMAL POINT 8 SEGMENT DRIVERS 8 DIGIT DRIVERS 3 7 1 INTERDIGIT BLANKING DECIMAL POINT 8 SEGMENT DRIVERS 8 DIGIT DRIVERS ICM7228 Absolute Maximum Ratings Thermal Information Supply Voltage (VDD - VSS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6V Digit Output Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 500mA Segment Output Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100mA Input Voltage (Note 1) (Any Terminal) . . (VSS -0.3V)<VIN <(VDD +0.3V) Thermal Resistance (Typical, Note 2) Operating Conditions Operating Temperature Range . . . . . . . . . . . . . . . . . -40oC to 85oC θJA (oC/W) PDIP Package* . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 SOIC Package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 Maximum Junction Temperature . . . . . . . . . . . . . . . . . . . . . . .150oC Maximum Storage Temperature Range . . . . . . . . . -65oC to 150oC Maximum Lead Temperature (Soldering 10s) . . . . . . . . . . . . .300oC (SOIC - Lead Tips Only) *Pb-free PDIPs can be used for through hole wave solder processing only. They are not intended for use in Reflow solder processing applications. 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 used to fabricate these devices, connecting any terminal to a voltage greater than VDD or less then VSS may cause destructive device latchup. For this reason, it is recommended that no inputs row sources operating on a different power supply be applied to the device before its own supply is established, and when using multiple supply systems the supply to the ICM7228 should be turned on first. 2. θJA is measured with the component mounted on a low effective thermal conductivity test board in free air. See Tech Brief 379 for details. Electrical Specifications VDD = +5.0V ±10%, VSS = 0V, Unless Otherwise Specified TA = 25oC PARAMETER TEST CONDITIONS Supply Voltage Range, VSUPPLY Quiescent Supply Current, IQ Operating Supply Current, IDD Digit Drive Current, IDIG Digit Leakage Current, IDLK Peak Segment Drive Current, ISEG Segment Leakage Current, ISLK 4 -40oC TO 85oC MIN TYP MAX MIN TYP MAX UNITS Operating 4 - 6 4 - 6 V Power Down Mode 2 - - 2 - - Shutdown, ICM7228A, IMC7228B - 1 100 - 1 100 Shutdown, 7228C - 2.5 100 - 2.5 100 Common Anode, ICM7228A/C Segments = ON; Outputs = OPEN - 200 450 - 200 450 Common Anode, ICM7228A/C Segments = OFF; Outputs = OPEN - 100 450 - 100 450 Common Cathode, ICM7228B Segments = ON; Outputs = OPEN - 250 450 - 250 450 Common Cathode, ICM7228B Segments = OFF; Outputs = OPEN - 175 450 - 175 450 Common Anode, ICM7228A/C VOUT = VDD - 2.0V 200 - - 175 - - Common Cathode, ICM7228B VOUT = VSS + 1.0V 50 - - 40 - - Shutdown Mode, VOUT = 2.0V Common Anode, ICM7228A/C - 1 100 - 1 100 Shutdown Mode, VOUT = 5.0V Common Cathode, 7228B - 1 100 - 1 100 Common Anode, ICM7228A/C VOUT = VSS + 1.0V 20 25 - 20 - - Common Cathode, 7228B VOUT = VDD - 2.0V 10 12 - 10 - - Shutdown Mode, VOUT = VDD Common Anode, ICM7228A/C - 1 50 - 1 50 Shutdown Mode, VOUT = VSS Common Cathode, ICM7228B - 1 50 - 1 50 µA µA mA µA mA µA ICM7228 Electrical Specifications VDD = +5.0V ±10%, VSS = 0V, Unless Otherwise Specified (Continued) TA = 25oC MIN TYP MAX MIN TYP MAX UNITS All Inputs Except Pin 9, ICM7228C, VIN = VSS - - 1 - - 1 µA All Inputs Except Pin 9, ICM7228C, VIN = 5.0V - - -1 - - -1 Per Digit - 390 - - 390 - Hz 2 10 - 2 - - µs PARAMETER TEST CONDITIONS Input Leakage Current, IIL Display Scan Rate, fMUX -40oC TO 85oC Inter-Digit Blanking Time, tIDB Logical “1” Input Voltage, VINH Three Level Input: Pin 9 ICM7228C, Hexadecimal VDD = 5V 4.2 - - 4.2 - - V Floating Input, VINF Three Level Input: Pin 9 ICM7228C, Code B, VDD = 5V 2.0 - 3.0 2.0 - 3.0 V Logical “0” Input Voltage, VINL Three Level Input: Pin 9 ICM7228C, Shutdown, VDD = 5V - - 0.8 - - 0.8 V Three Level Input Impedance, ZIN VCC = 5V, Pin 9 of ICM7228C 50 - - 50 - - kΩ Logical “1” Input Voltage, VIH All Inputs Except, Pin 9 of ICM7228C, VDD = 5V 2.0 - - 2.0 - - V Logical “0” Input Voltage, VIL All Inputs Except, Pin 9 of ICM7228C, VDD = 5V - - 0.8 - - 0.8 V SWITCHING SPECIFICATIONS VDD = +5.0V ±10%, VSS = 0V, VIL = +0.4V, VIH = +2.4V Write Pulsewidth (Low), tWL 200 100 - 250 - - ns Write Pulsewidth (High), tWH 850 540 - 1200 - - ns Mode Hold Time, tMH ICM7228A, ICM7228B 0 -65 - 0 - - ns Mode Setup Time, tMS ICM7228A, ICM7228B 250 150 - 250 - - ns Data Setup Time, tDS 250 160 - 250 - - ns Data Hold Time, tDH 0 -60 - 0 - - ns Digit Address Setup Time, tAS ICM7228C 250 110 - 250 - - ns Digit Address Hold Time, tAH ICM7228C 0 -60 - 0 - - ns 5 ICM7228 Timing Diagrams MODE tMS tMH WRITE MODE tWH tWL WRITE INPUT DATA CONTROL WORD TYPE OF DECODER?ID6 DECODE/NO DECODE? ID5 SHUTDOWN?ID4 DATA COMING ID7 tDH tDS VALID FIGURE 1. ICM7228A/B WRITE CYCLE DIGIT ADDRESS DAO-DAZ WRITE DATA 8 PULSES (D1) VALID tAS tAH tWL tWH tDH tDS DATA VALID DATA FIGURE 3. ICM7228C WRITE CYCLE 10µs (TYP) FREE RUNNING 320µs (TYP) FREE RUNNING (PER DIGIT) INTERDIGIT BLANKING INTERNAL SIGNAL D2 D5 INTERDIGIT BLANKING D1 D7 D8 D6 D4 D3 FIGURE 4. DISPLAY DIGITS MULTIPLEX (COMMON ANODE DISPLAY) 6 DON’T CARE CONTROL WORD TYPE OF DECODER?ID6 DECODE/NO DECODE? ID5 SHUTDOWN? ID4 DATA COMING ID7 FIGURE 2. ICM7228A/B SEQUENTIAL 8-DIGIT RAM UPDATE WRITE TYPICAL DIGITS OUTPUT PULSES (D8) ICM7228 Typical Performance Curves 0 -55oC 100 125oC 25oC 300 ISEG (mA) IDIG (mA) -55oC 80 200 25oC 125oC 25oC 60 125oC 40 400 20 500 -55oC 0 5.0 4.0 3.0 2.0 1.0 0 0 1.0 2.0 3.0 4.0 5.0 VSEG (V) VDD-VDIG (V) FIGURE 5. COMMON ANODE DIGIT DRIVER IDIG vs (VDD - VDIG) FIGURE 6. COMMON ANODE SEGMENT DRIVER ISEG vs VSEG 25oC -55oC 0 10 125oC ISEG (mA) IDIG (mA) 20 300 -55oC 200 25oC 125oC 100 30 40 50 0 0 1.0 2.0 3.0 4.0 5.0 5.0 4.0 3.0 2.0 1.0 0 VDD-VSEG (V) VDIG (V) FIGURE 7. COMMON CATHODE DIGIT DRIVER IDIG vs VDIG FIGURE 8. COMMON CATHODE SEGMENT DRIVER ISEG vs (VDD - VSEG) TABLE 1. ICM7228A PIN ASSIGNMENTS AND DESCRIPTIONS PIN NO. NAME FUNCTION Output DESCRIPTION 1 SEG c 2 SEG e 3 SEG b 4 DP 5 ID6, (HEXA/CODE B) Input When “MODE” Low: Display Data Input, Bit 7. When “MODE” High: Control Bit, Decoding Scheme Selection: High, Hexadecimal Decoding; Low, Code B Decoding. 6 ID5, (DECODE) Input When “MODE” Low: Display Data Input, Bit 6. When “MODE” High: Control Bit, Decode/No Decode Selection: High, No Decode; Low, Decode. 7 ID7, (DATA COMING) Input When “MODE” Low: Display Data Input, Bit 8, Decimal Point Data. When “MODE” High: Control Bit, Sequential Data Update Select: High, Data Coming; Low, No Data Coming. 8 WRITE Input Data Input Will Be Written to Control Register or Display RAM on Rising Edge of WRITE. 7 LED Display Segments c, e, b and Decimal Point Drive Lines. ICM7228 TABLE 1. ICM7228A PIN ASSIGNMENTS AND DESCRIPTIONS (Continued) PIN NO. NAME FUNCTION DESCRIPTION 9 MODE Input Selects Data to Be Loaded to Control Register or Display RAM: High, Loads Control Register; Low, Loads Display RAM. 10 ID4, (SHUTDOWN) Input When “MODE” Low: Display Data Input, Bit 5. When “MODE” High: Control Bit, Low Power Mode Select: High, Normal Operation; Low, Oscillator and Display Disabled. 11 ID1 Input When “MODE” Low: Display Data Input, Bit 2. When “MODE” High and “ID7 (DATA COMING)” Low: Digit Address, Bit 2, Single Digit Update Mode. 12 ID0 Input When “MODE” Low: Display Data Input, Bit 1. When “MODE” High and “ID7 (DATA COMING)” Low: Digit Address, LSB, Single Digit Update Mode. 13 ID2 Input When “MODE” Low: Display Data Input, Bit 3. When “MODE” High and “ID7 (DATA COMING)” Low: Digit Address, MSB, Single Digit Update Mode. 14 ID3 Input When “MODE” Low: Display Data Input, Bit 4. When “MODE” High: RAM Bank Select (Decode Modes Only): High, RAM Bank A; Low, RAM Bank B 15 DIGIT 1 16 DlGlT 2 17 DIGIT 5 18 DlGlT 8 19 Output LED Display Digits 1, 2, 5 and 8 Drive Lines. VDD Supply Device Positive Power Supply Rail. 20 DIGIT 4 Output LED Display Digits 4, 7, 6 and 3 Drive Lines. 21 DlGlT 7 22 DlGlT 6 23 DIGlT 3 24 SEG f Output LED Display Segments f, d, g and a Drive Lines. 25 SEG d 26 SEG g 27 SEG a 28 VSS Supply Device Ground or Negative Power Supply Rail. TABLE 2. ICM7228B PIN ASSIGNMENTS AND DESCRIPTIONS PIN NO. NAME FUNCTION Output DESCRIPTION 1 DIGIT 4 2 DlGlT 6 3 DIGIT 3 4 DlGlT 1 5 ID6, (HEXA/CODE B) Input When “MODE” Low: Display Data Input, Bit 7. When “MODE” High: Control Bit, Decoding Scheme Selection: High, Hexadecimal Decoding; Low, Code B Decoding. 6 ID5, (DECODE) Input When “MODE” Low: Display Data Input, Bit 6. When “MODE” High: Control Bit, Decode/No Decode Selection: High, No Decode; Low, Decode. 7 ID7, (DATA COMING) Input When “MODE” Low: Display Data Input, Bit 8, Decimal Point Data. When “MODE” High: Control Bit, Sequential Data Update Select: High, Data Coming; Low, No Data Coming. 8 LED Display Digits 4, 6, 3 and 1 Drive Lines. ICM7228 TABLE 2. ICM7228B PIN ASSIGNMENTS AND DESCRIPTIONS (Continued) PIN NO. NAME FUNCTION DESCRIPTION 8 WRITE Input Data Input Will Be Written to Control Register or Display RAM on Rising Edge of WRITE. 9 MODE Input Selects Data to Be Loaded to Control Register or Display RAM: High, Loads Control Register; Low, Loads Display RAM. 10 ID4, (SHUTDOWN) Input When “MODE” Low: Display Data Input, Bit 5. When “MODE” High: Control Bit, Low Power Mode Select: High, Normal Operation; Low, Oscillator and Display Disabled. 11 ID1 Input When “MODE” Low: Display Data Input, Bit 2. When “MODE” High and “ID7 (DATA COMING)” Low: Digit Address, Bit 2, Single Digit Update Mode. 12 ID0 Input When “MODE” Low: Display Data Input, Bit 1. When “MODE” High and “ID7 (DATA COMING)” Low: Digit Address, LSB, Single Digit Update Mode. 13 ID2 Input When “MODE” Low: Display Data Input, Bit 3. When “MODE” High and “ID7 (DATA COMING)” Low: Digit Address, MSB, Single Digit Update Mode. 14 ID3 Input When “MODE” Low: Display Data Input, Bit 4. When “MODE” High: RAM Bank Select (Decode Modes Only): High, RAM Bank A; Low, RAM Bank B. 15 DP Output LED Display Decimal Point and Segments a, b, and d Drive Lines 16 SEG a 17 SEG b 18 SEG d 19 VDD Supply Device Positive Power Supply Rail. 20 SEG c Output LED Display Segments c, e, f and g Drive Lines. 21 SEG e 22 SEG f 23 SEG g 24 DIGIT 8 Output LED Display Digits 8, 2, 5 and 7 Drive Lines. 25 DIGIT 2 26 DIGIT 5 27 DIGIT 7 28 VSS Supply Device Ground or Negative Power Supply Rail. TABLE 3. ICM7228C PIN ASSIGNMENTS AND DESCRIPTIONS PIN NO. NAME FUNCTION Output DESCRIPTION 1 SEG c 2 SEG e 3 SEG b 4 DP 5 DA0 Input Digit Address Input, Bit 1 LSB. 6 DA1 Input Digit Address Input, Bit 2. 7 ID7, (INPUT DP) Input Display Decimal Point Data Input, Negative True. 8 WRITE Input Data Input Will Be Written to Display RAM on Rising Edge of WRITE. 9 LED Display Segments c, e, band Decimal Point Drive Lines. ICM7228 TABLE 3. ICM7228C PIN ASSIGNMENTS AND DESCRIPTIONS (Continued) PIN NO. NAME FUNCTION DESCRIPTION 9 HEXA/CODE B/SHUTDOWN Input Three Level Input. Display Function Control: High, Hexadecimal Decoding; Float, Code B Decoding; Low, Oscillator, and Display Disabled. 10 DA2 Input Digit Address Input, Bit 3, MSB. 11 ID1 Input Display Data Inputs. 12 ID0 13 ID2 14 ID3 15 DIGIT 1 16 DlGlT 2 17 DIGIT 5 18 DlGlT 8 19 Output LED Display Digits 1, 2, 5 and 8 Drive Lines. VDD Supply Device Positive Power Supply Rail. 20 DIGIT 4 Output LED Display Digits 4, 7, 6 and 3 Drive Lines. 21 DlGlT 7 22 DlGlT 6 23 DIGlT 3 24 SEG f Output LED Display Segments f, d, g and a Drive Lines. 25 SEG d 26 SEG g 27 SEG a 28 VSS Supply Device Ground or Negative Power Supply Rail. Detailed Description System Interfacing and Data Entry Modes, ICM7228A and ICM7228B The ICM7228A/B devices are compatible with the architectures of most microprocessor systems. Their fast switching characteristics makes it possible to access them as a memory mapped I/O device with no wait state necessary in most microcontroller systems. All the ICM7228A/B inputs, including MODE, feature a 250ns minimum setup and 0ns hold time with a 200ns minimum WRITE pulse. Input logic levels are TTL and CMOS compatible. Figure 9 shows a generic method of driving the ICM7228A/B from a microprocessor bus. To the microprocessor, each device appears to be 2 separate I/O locations; the Control Register and the Display RAM. Selection between the two is accomplished by the MODE input driven by address line A0. Input data is placed on the lD0 - lD7 lines. The WRITE input acts as both a device select and write cycle timing pulse. See Figure 1 and Switching Specifications Table for write cycle timing parameters. The ICM7228A/B have three data entry modes: Control Register update without RAM update, sequential 8-digit update and single digit update. In all three modes a control word is first written by pulsing the WRITE input while the 10 MODE input is high, thereby latching data into the Control Register. The logic level of individual bits in the Control Register select Shutdown, Decode/No Decode, Hex/Code B, RAM bank A/B and Display RAM digit address as shown in Tables 1 and 2. The ICM7228A/B Display RAM is divided into 2 banks, called bank A and B. When using the Hexadecimal or code B display modes, these RAM banks can be selected separately. This allows two separate sets of display data to be stored and displayed alternately. Notice that the RAM bank selection is not possible in No-Decode mode, this is because the display data in the No-Decode mode has 8 bits, but in Decoded schemes (Hex/Code B) is only 4 bits (lD0 - lD3 data). It should also be mentioned that the decimal point is independent of selected bank, a turned on decimal point will remain on for either bank. Selection of the RAM banks is controlled by lD3 input. The lD3 logic level (during Control Register update) selects which bank of the internal RAM to be written to and/or displayed. Control Register Update without RAM Update The Control Register can be updated without changing the display data by a single pulse on the WRITE input, with MODE high and DATA COMING low. If the display is being decoded (Hex/Code B), then the value of lD3 determines which RAM bank will be selected and displayed for all eight digits. ICM7228 Sequential 8-Digit Update Single Digit Update The logic state of DATA COMING (lD7) is also latched during a Control Register update. If the latched value of DATA COMING (lD7) is high, the display becomes blanked and a sequential 8-digit update is initiated. Display data can now be written into RAM with 8 successive WRITE pulses, starting with digit 1 and ending with digit 8 (See Figure 2). After all 8 RAM locations have been written to, the display turns on again and the new data is displayed. Additional write pulses are ignored until a new Control Register update is performed. All 8 digits are displayed in the format (Hex/Code B or No Decode) specified by the control word that preceded the 8 digit update. If a decoding scheme (Hex/Code B) is to be used, the value of lD3 during the control word update determines which RAM bank will be written to. In this mode each digit data in the display RAM can be updated individually without changing the other display data. First, with MODE input high, a control word is written to the Control Register carrying the following information; DATA COMING (lD7) low, the desired display format data on lD4 - lD6, the RAM bank selected by lD3 (if decoding is selected) and the address of the digit to be updated on data lines lD0 - lD2 (See Table 4). A second write to the ICM7228A/B, this time with MODE input low, transfers the data at the lD0 - lD7 inputs into the selected digit’s RAM location. In single digit update mode, each individual digit’s data can be specified independently for being displayed in Decoded or No-Decode mode. For those digits which decoding scheme (Hex/Code B) is selected, only one can be effective at a time. Whenever a control word is written, the specified decoding scheme will be applied to all those digits which selected to be displayed in Decoded mode. DATA BUS D0-D7 MICROPROCESSOR SYSTEM ID0 D0 - D7 ID7 I/O OR MEMORY WRITE PULSE DECODER ENABLE INTERSIL ICM7228A/B DEVICE SELECT AND WRITE PULSE LED DISPLAY SEGMENTS DRIVE WRITE ADDRESS DECODER A1-A15 A0 MODE DIGITS DRIVE ADDRESS BUS A0 - A15 FIGURE 9. ICM7228A/B MICROPROCESSOR SYSTEM INTERFACING TABLE 4. DIGITS ADDRESS, ICM7228A/B INPUT DATA LINES 1D2 lD2 lD0 SELECTED DIGIT 0 0 0 DlGlT 1 0 0 1 DlGlT 2 0 1 0 DIGlT 3 0 1 1 DlGlT 4 1 0 0 DIGIT 5 1 0 1 DlGlT 6 1 1 0 DlGlT 7 1 1 1 DlGlT 8 System Interfacing, ICM7228C The ICM7228C is directly compatible with the architecture of most microprocessor systems. Its fast switching characteristics make it possible to access them as a memory mapped I/O device with no wait state necessary in most microcontroller systems. All the ICM7228C inputs, excluding HEXA/CODE B/SHUTDOWN, feature a 250ns minimum 11 setup and 0ns hold time with a 200ns minimum WRITE pulse. Input logic levels are TTL and CMOS compatible. Figure 10 shows a generic method of driving the ICM7228C from a microprocessor bus. To the microprocessor, the 8 bytes of the Display RAM appear to be 8 separate I/O locations. Loading the ICM7228C is quite similar to a standard memory write cycle. The address of the digit to be updated is placed on lines DA0 - DA2, the data to be written is placed on lines ID0 - lD3 and ID7, then a low pulse on WRITE input will transfer the data in. See Figure 3 and Switching Characteristics Table for write cycle timing parameters. The ICM7228C does not have any control register, and also does not provide the No Decode display format. Hexadecimal or Code B character selection and shutdown mode are directly controlled through the three level input at Pin 9, which is accordingly called HEXA/CODE B/SHUTDOWN. See Table 3 for input and output definitions of the ICM7228C. ICM7228 Display Formats TABLE 5. DISPLAY CHARACTER SETS (Continued) The ICM7228A and ICM7228B have three possible display formats; Hexadecimal, Code B and No Decode. Table 5 shows the character sets for the decode modes and their corresponding input code. INPUT DATA CODE The display formats of the ICM7228A/B are selected by writing data to bits ID4, ID5 and ID6 of the Control Register (See Table 1 and 2 for input Definitions). Hexadecimal and Code B data is entered via ID0-lD3 and ID7 controls the decimal point. TABLE 5. DISPLAY CHARACTER SETS INPUT DATA CODE ID3 ID2 ID1 DISPLAY CHARACTERS ID0 HEXADECIMAL CODE B 0 0 0 0 0 0 0 0 0 1 1 1 0 0 1 0 2 2 MICROPROCESSOR SYSTEM DATA BUS D0 - D7 I/O OR MEMORY WRITE PULSE DECODER ENABLE DISPLAY CHARACTERS ID3 ID2 ID1 ID0 HEXADECIMAL CODE B 0 0 1 1 3 3 0 1 0 0 4 4 0 1 0 1 5 5 0 1 1 0 6 6 0 1 1 1 7 7 1 0 0 0 8 8 1 0 0 1 9 9 1 0 1 0 A - 1 0 1 1 b E 1 1 0 0 C H 1 1 0 1 d L 1 1 1 0 E P 1 1 1 1 F (Blank) 5 DEVICE SELECT AND WRITE PULSE ID0 - ID3 AND ID7 INTERSIL ICM7228C SEGMENTS DRIVE WRITE LED DISPLAY ADDRESS DECODER A0 - A2 A3 - A15 DA0 - DA2 DIGITS DRIVE ADDRESS BUS A0 - A15 FIGURE 10. ICM7228C MICROPROCESSOR SYSTEM INTERFACING An input high level turns on the respective segment, except for the decimal point, which is turned on by an input low level on ID7. a f b g e c d The No Decode mode can be used in different applications such as bar graph or status panel driving where each segment controls an individual LED. DP FIGURE 11. DIGITS SEGMENT ASSIGNMENTS The No Decode mode of the ICM7228A and ICM7228B allows the direct segment-by-segment control of all 64 segments driven by the device. In the No Decode mode, the input data directly control the outputs as shown in Table 6. Shutdown and Display Banking TABLE 6. NO DECODE SEGMENT LOCATIONS DATA INPUT ID7 ID6 ID5 ID4 ID3 ID2 ID1 ID0 Controlled Segment Decimal Point a b c e g f d 12 The ICM7228C has only the Hexadecimal and Code B character sets. The HEXA/CODE B/SHUTDOWN input, pin 9, requires a three level input. Pin 9 selects the Hexadecimal format when pulled high, the Code B format when floating or driven to mid-supply, and the shutdown mode when pulled low (See Table 3). Table 5 also applies to the ICM7228C. When shutdown, the ICM7228 enters a low power standby mode typically consuming only 1µA of supply current for the ICM7228A/B and 2.5µA for the ICM7228C. In this mode the ICM7228 turns off the multiplex scan oscillator as well as the digit and segment drivers. However, input data can still be ICM7228 entered when in the shutdown mode. Data is retained in memory even with the supply voltage as low as 2V. The ICM7228A/B is shutdown by writing a control word with Shutdown (lD4) low. The ICM7228C is put into shutdown mode by driving pin 9, HEXA/CODE B/SHUTDOWN, low. The ICM7228 operating current with the display blanked is within 100µA - 200µA for all versions. All versions of the ICM7228 can be blanked by writing Hex FF to all digits and selecting Code B format. The ICM7228A and ICM7228B can also be blanked by selecting No Decode mode and writing Hex 80 to all digits (See Tables 5and 6). Common Anode Display Drivers, ICM7228A and ICM7228C The common anode digit and segment driver output schematics are shown in Figure 12. The common anode digit driver output impedance is approximately 4Ω. This provides a nearly constant voltage to the display digits. Each digit has a minimum of 200mA drive capability. The N-Channel segment driver’s output impedance of 50Ω limits the segment current to approximately 25mA peak current per segment. Both the segment and digit outputs can directly drive the display, current limiting resistors are not required. Individual segment current is not significantly affected by whether other segments are on or off. This is because the segment driver output impedance is much higher than that of the digit driver. This feature is important in bar graph applications where each bar graph element should have the same brightness, independent of the number of elements being turned on. ghosting (a faint display of data from previous digit superimposed on the next digit). The interdigit blanking time is 10µs typical with a guaranteed 2µs minimum. The ICM7228 turns off both the digit drivers and the segment drivers during the interdigit blanking period. The digit multiplexing sequence is: D2, D5, D1, D7, D8, D6, D4 and D3. A typical digit’s drive pulses are shown on Figure 4. Due to the display multiplexing, the driving duty cycle for each digit is 12% (100 x 1/8) This means the average current for each segment is 1/8 of its peak current. This must be considered while designing and selecting the displays. Driving Larger Displays If very high display brightness is desired, the ICM7228 display driver outputs can be externally buffered. Figures 14 thru 16 show how to drive either common anode or common cathode displays using the ICM7228 and external driver circuit for higher current displays. Another method of increasing display currents is to connect two digit outputs together and load the same data into both digits. This drives the display with the same peak current, but the average current doubles because each digit of the display is on for twice as long, i.e., 1/4 duty cycle versus 1/8 . VDD DIGIT STROBE P ≈200mA INTERDIGIT BLANKING Common Cathode Display Driver, ICM7228B The common cathode digit and segment driver output schematics are shown in Figure 13. The N-channel digit drivers have an output impedance of approximately 15Ω. Each digit has a minimum of 50mA drive capability. The segment drivers have an output impedance of approximately 100Ω with typically 10mA peak current drive for each segment. The common cathode display driver output currents are only 1/4 of the common anode display driver currents. Therefore, the ICM7228A and ICM7228C common anode display drivers are recommended for those applications where high display brightness is desired. The ICM7228B common cathode display driver is suitable for driving bubble-lensed monolithic 7 segment displays. They can also drive individual LED displays up to 0.3 inches in height when high brightness is not required. Display Multiplexing Each digit of the ICM7228 is on for approximately 320µs, with a multiplexing frequency of approximately 390Hz. The ICM7228 display drivers provide interdigit blanking. This ensures that the segment information of the previous digit is gone and the information of the next digit is stable before the next digit is driven on. This is necessary to eliminate display 13 N N N ≈2kΩ VSS COMMON ANODE DIGIT OUTPUT N ≈2kΩ SHUTDOWN VSS NOTE: When SHUTDOWN goes low INTERDIGIT BLANKING also stays low. FIGURE 12A. DIGIT DRIVER ICM7228 VDD VDD VDD P ≈2kΩ SEGMENT DATA INTERDIGIT BLANKING N ≈75Ω SHUTDOWN COMMON ANODE SEGMENT OUTPUT UP TO 4A DIGIT OUTPUT ICM7228A/C VSS VDD VDD FIGURE 12B. SEGMENT DRIVER SEGMENT OUTPUT FIGURE 12. COMMON ANODE DISPLAY DRIVERS 10K VDD P ≈2kΩ DIGIT STROBE INTERDIGIT BLANKING N ≈15Ω SHUTDOWN VSS COMMON CATHODE DIGIT OUTPUT VSS FIGURE 14. DRIVING HIGH CURRENT DISPLAY, COMMON ANODE ICM7228A/C TO COMMON ANODE VDD VDD VSS SEGMENT OUTPUT 100Ω FIGURE 13A. DIGIT DRIVER 2N2219 ICM7228B VDD VDD SEGMENT DATA DIGIT OUTPUT ≈200mA P 14Ω (100mAPEAK) 14mA 2N6034 INTERDIGIT BLANKING 100Ω N ≈2kΩ N VSS COMMON CATHODE SEGMENT OUTPUT N ≈2kΩ SHUTDOWN VSS NOTE: When SHUTDOWN goes low INTERDIGIT BLANKING also stays low. FIGURE 13B. SEGMENT DRIVER FIGURE 13. COMMON CATHODE DISPLAY DRIVERS 14 N ≈15Ω VSS 1.4APEAK VSS FIGURE 15. DRIVING HIGH CURRENT DISPLAY, COMMON CATHODE ICM7228B TO COMMON CATHODE DISPLAY ICM7228 Power Supply Bypassing VDD VDD VDD Connect a minimum of 47µF in parallel with 0.1µF capacitors between VDD and VSS of ICM7228. These capacitors should be placed in close proximity to the device to reduce the power supply ripple caused by the multiplexed LED display drive current pulses. 1.4APEAK 1K 2N6034 100Ω SEGMENT OUTPUT ICM7228B VDD DIGIT OUTPUT 1K 300Ω 25Ω (100mAPEAK) 2N2219 N ≈15Ω 1K VSS VSS FIGURE 16. DRIVING HIGH CURRENT DISPLAY, COMMON CATHODE ICM7228B TO COMMON ANODE DISPLAY Three Level Input, ICM7228C As mentioned before, pin 9 is a three level input and controls three functions: Hexadecimal display decoding, Code B display decoding and shutdown mode. In many applications, pin 9 will be left open or permanently wired to one state. When pin 9 can not be permanently left in one state, the circuits illustrated in Figure 17 can be used to drive this three level input. HIGH = HEX 74C126 THREE-STATE BUFFER PIN 9 LOW = SHUTDOWN HIGH = HEX OR SHUTDOWN LOW = CODE B CD4016 CD4066 HIGH = HEX PIN 9 LOW = SHUTDOWN CONTROL HIGH = HEX OR SHUTDOWN LOW = CODE B CD4069 HIGH = CODE B 1N4148 PIN 9 LOW = HEX CD4069 HIGH = SHUTDOWN 1N4148 PIN 9 LOW = CODE B CD4069 HIGH = SHUTDOWN LOW = HEX PIN 9 OPEN DRAIN OR OPEN COLLECTOR OUTPUT HIGH = SHUTDOWN PIN 9 LOW = CODE B FIGURE 17. ICM7228C PIN 9 DRIVE CIRCUITS 15 ICM7228 Test Circuit ID6 (HEXA/CODE B) ID5 (DECODE) ID7 (DATA COMING) WRITE MODE ID4 (SHUTDOWN) ID1 ID0 ID2 ID3 VDD 1 28 2 27 3 26 4 25 5 24 6 23 22 7 ICM7228A 8 21 9 20 10 19 11 18 12 17 13 16 14 15 f VDD + d 47µF +0.1µF 5V VSS g a VSS D8 D7 D6 D5 D4 COMMON ANODE DISPLAY D3 D2 D1 c e b DP FIGURE 18. FUNCTIONAL TEST CIRCUIT #1 16 ICM7228 Dual-In-Line Plastic Packages (PDIP) E28.6 (JEDEC MS-011-AB ISSUE B) N 28 LEAD DUAL-IN-LINE PLASTIC PACKAGE E1 INDEX AREA 1 2 3 INCHES N/2 SYMBOL -B- -C- A2 SEATING PLANE e B1 D1 A1 eC B 0.010 (0.25) M C A B S MAX NOTES - 0.250 - 6.35 4 0.015 - 0.39 - 4 A2 0.125 0.195 3.18 4.95 - B 0.014 0.022 0.356 0.558 - C L B1 0.030 0.070 0.77 1.77 8 eA C 0.008 0.015 0.204 0.381 - D 1.380 1.565 D1 0.005 - A L D1 MIN A E BASE PLANE MAX A1 -AD MILLIMETERS MIN C eB NOTES: 1. Controlling Dimensions: INCH. In case of conflict between English and Metric dimensions, the inch dimensions control. 2. Dimensioning and tolerancing per ANSI Y14.5M-1982. 35.1 39.7 5 - 5 0.13 E 0.600 0.625 15.24 15.87 6 E1 0.485 0.580 12.32 14.73 5 e 0.100 BSC 2.54 BSC - eA 0.600 BSC 15.24 BSC 6 3. Symbols are defined in the “MO Series Symbol List” in Section 2.2 of Publication No. 95. eB - 0.700 - 17.78 7 L 0.115 0.200 2.93 5.08 4 4. Dimensions A, A1 and L are measured with the package seated in JEDEC seating plane gauge GS-3. N 5. D, D1, and E1 dimensions do not include mold flash or protrusions. Mold flash or protrusions shall not exceed 0.010 inch (0.25mm). 6. E and eA are measured with the leads constrained to be perpendicular to datum -C- . 7. eB and eC are measured at the lead tips with the leads unconstrained. eC must be zero or greater. 8. B1 maximum dimensions do not include dambar protrusions. Dambar protrusions shall not exceed 0.010 inch (0.25mm). 9. N is the maximum number of terminal positions. 10. Corner leads (1, N, N/2 and N/2 + 1) for E8.3, E16.3, E18.3, E28.3, E42.6 will have a B1 dimension of 0.030 - 0.045 inch (0.76 - 1.14mm). 17 28 28 9 Rev. 1 12/00 ICM7228 Small Outline Plastic Packages (SOIC) M28.3 (JEDEC MS-013-AE ISSUE C) N 28 LEAD WIDE BODY SMALL OUTLINE PLASTIC PACKAGE INDEX AREA H 0.25(0.010) M B M INCHES E SYMBOL -B- 1 2 3 L SEATING PLANE -A- h x 45o A D -C- e A1 B C 0.10(0.004) 0.25(0.010) M C A M B S MILLIMETERS MIN MAX NOTES A 0.0926 0.1043 2.35 2.65 - 0.0040 0.0118 0.10 0.30 - B 0.013 0.0200 0.33 0.51 9 C 0.0091 0.0125 0.23 0.32 - D 0.6969 0.7125 17.70 18.10 3 E 0.2914 0.2992 7.40 7.60 4 0.05 BSC 10.00 h 0.01 0.029 0.25 0.75 5 L 0.016 0.050 0.40 1.27 6 8o 0o 28 0o 10.65 - 0.394 N 0.419 1.27 BSC H α NOTES: MAX A1 e α MIN 28 - 7 8o 1. Symbols are defined in the “MO Series Symbol List” in Section 2.2 of Publication Number 95. Rev. 0 12/93 2. Dimensioning and tolerancing per ANSI Y14.5M-1982. 3. Dimension “D” does not include mold flash, protrusions or gate burrs. Mold flash, protrusion and gate burrs shall not exceed 0.15mm (0.006 inch) per side. 4. Dimension “E” does not include interlead flash or protrusions. Interlead flash and protrusions shall not exceed 0.25mm (0.010 inch) per side. 5. The chamfer on the body is optional. If it is not present, a visual index feature must be located within the crosshatched area. 6. “L” is the length of terminal for soldering to a substrate. 7. “N” is the number of terminal positions. 8. Terminal numbers are shown for reference only. 9. The lead width “B”, as measured 0.36mm (0.014 inch) or greater above the seating plane, shall not exceed a maximum value of 0.61mm (0.024 inch) 10. Controlling dimension: MILLIMETER. Converted inch dimensions are not necessarily exact. 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 18