HI-8045

HI-8045 August 2005 CMOS HIGH VOLTAGE DISPLAY DRIVER APPLICATIONS ! Dichroic Liquid Crystal Displays ! Standard Liquid Crystal Displays ! MEMS Drivers GENERAL DESCRIPTION The HI-8045 high voltage display driver is a low cost plastic, 80-segment version of the Holt HI-8040 display driver series. The 20 mil package lead pitch allows the maximum number of display driver segments in the smallest space. An optional voltage converter can generate the negative display drive voltage. Test inputs facilitate opens and shorts testing. The backplane frequency is checked and, as long as power is available, the segments are shut "Off" if the frequency becomes too low. The HI-8045 and the HI-80XX series of display drivers all control segment information in the same way. Data is serially clocked into the device and the data for all segment outputs are latched in parallel when the Load input transitions from high to low. With the Data Out from the shift register available, devices may be cascaded to obtain more segment outputs. The shift register is 85 bits long. The die is metal mask programmable to provide for various package and/or cascade tap options. Consult your Holt Sales representative to explore the possibilities. PIN CONFIGURATION (Top View) S80 S79 S78 S77 S76 S75 S74 S73 S72 S71 S70 S69 S68 S67 S66 S65 S64 S63 S62 S61 S60 S59 S58 S57 S56 N/C VSS CS CL LD DIN BPOSC N/C N/C BPIN N/C CONVOUT VDD DOUT 85 CONVOSC VEE T1 T2 BP S1 S2 S3 S4 S5 S6 99 98 97 96 95 94 93 92 91 90 89 88 87 86 85 84 83 82 81 80 79 78 77 76 75 74 73 72 71 70 69 68 67 66 65 64 63 62 61 60 59 58 57 56 55 54 53 52 51 FEATURES ! 4 MHz serial input data rate ! 80 segment outputs ! Cascadable ! 5 Volt inputs translated to 35 Volts ! Test pins allow hardware all "ON", all "OFF" or alternating ! Monitors backplane oscillation and forces all segments to "OFF" condition if below 10Hz ! Negative voltage converter available on-chip ! CMOS low power ! Industrial and JEDEC processing available FUNCTIONAL BLOCK DIAGRAM DIN CL CS LD BPOSC BPIN Þ Þ Þ Þ Þ Þ S7 S8 S9 S10 S11 S12 S13 S14 S15 S16 S17 S18 S19 S20 S21 S22 S23 S24 S25 S26 S27 S28 S29 S30 N/C 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 HI-8045PQ 80 - SEGMENT 100 - PIN PLASTIC QUAD FLAT PACK S55 S54 S53 S52 S51 S50 S49 S48 S47 S46 S45 S44 S43 S42 S41 S40 S39 S38 S37 S36 S35 S34 S33 S32 S31 DATA IN 8 5 Sta g e S h i ft R e g i s t e r CLK Þ DOUT 85 LE 80 Bit Latch Oscillator Divider Vo l ta g e Tr a n s l a t o r H i g h Vo l ta g e B u ff e r Vo l ta g e Tr a n s l a t o r s H i g h Vo l ta g e Drivers Þ BP (DS8045 Rev. D) 80 SEGMENTS HOLT INTEGRATED CIRCUITS www.holtic.com 08/05 HI-8045 FUNCTIONAL DESCRIPTION INPUT LOGIC CS must be held low to enter data into the shift register. The data is clocked on the negative edge of CL. LD is normally held low and only pulsed high when new data is ready for display. When LD is high the latch is transparent. All four logic inputs are TTL compatible. A logic "1" at DIN that is eventually latched to the segment drivers will cause the segment to be at the opposite voltage level of the BP pin (out of phase). BPOSC and BPIN The user can either make an oscillator to create the backplane frequency or drive an external clock into BPIN leaving BPOSC open. To make an oscillator, pins BPOSC and BPIN must be connected together and the appropriate R and C combination applied (See Figure 1). If the oscillator is used, the backplane frequency is approximately 1 fBP = (for R = 180KW & C = 220pF, fBP » 100Hz). 256 RC VEE & NEGATIVE VOLTAGE CONVERTER VEE may be externally driven to a maximum -30V. Alternatively, there is a voltage converter that will provide -21.4 volts (See Figure 2). If the converter pins are left open circuit, an on-chip sense resistor will cause shut down of all current consumption associated with the converter. The converter will survive a shorted segment condition and continue to maintain VEE at -20 volts. DOUT The DOUT pin is available from segment 85 for cascading devices to drive more segments and for verifying the data integrity. However only the first 80 output segments are available to the user. This output can drive 2 TTL loads. It changes on the positive edge of CL. AUTOMATIC SEGMENTS OFF The internal backplane signal is tested continuously to be at least 10Hz. If the detector senses f