MC14553B 3-Digit BCD Counter The MC14553B 3digit BCD counter consists of 3 negative edge triggered BCD counters that are cascaded synchronously. A quad latch at the output of each counter permits storage of any given count. The information is then time division multiplexed, providing one BCD number or digit at a time. Digit select outputs provide display control. MC14553B TRUTH TABLE Inputs Master Reset Clock Disable LE Outputs 0 0 0 No Change 0 0 0 Advance 0 X 1 X No Change 0 1 0 Advance 0 1 0 No Change 0 0 X X No Change 0 X X Latched 0 X X 1 Latched 1 X X 0 Q0 = Q1 = Q2 = Q3 = 0 X = Dont Care ELECTRICAL CHARACTERISTICS (Voltages Referenced to V ) SS 55 C 25 C 125 C V DD Typ (Note 2) Characteristic Symbol Vdc Min Max Min Max Min Max Unit Output Voltage 0 Level V 5.0 0.05 0 0.05 0.05 Vdc OL V = V or 0 10 0.05 0 0.05 0.05 in DD 15 0.05 0 0.05 0.05 1 Level V 5.0 4.95 4.95 5.0 4.95 Vdc OH V = 0 or V 10 9.95 9.95 10 9.95 in DD 15 14.95 14.95 15 14.95 Input Voltage 0 Level V Vdc IL (V = 4.5 or 0.5 Vdc) 5.0 1.5 2.25 1.5 1.5 O (V = 9.0 or 1.0 Vdc) 10 3.0 4.50 3.0 3.0 O (V = 13.5 or 1.5 Vdc) 15 4.0 6.75 4.0 4.0 O 1 Level V Vdc IH (V = 0.5 or 4.5 Vdc) 5.0 3.5 3.5 2.75 3.5 O (V = 1.0 or 9.0 Vdc) 10 7.0 7.0 5.50 7.0 O (V = 1.5 or 13.5 Vdc) 15 11 11 8.25 11 O Output Drive Current I mAdc OH (V = 4.6 Vdc) Source 5.0 0.25 0.2 0.36 0.14 OH (V = 9.5 Vdc) Pin 3 10 0.62 0.5 0.9 0.35 OH (V = 13.5 Vdc) 15 1.8 1.5 3.5 1.1 OH (V = 4.6 Vdc) Source 5.0 0.64 0.51 0.88 0.36 mAdc OH (V = 9.5 Vdc) Other 10 1.6 1.3 2.25 0.9 OH (V = 13.5 Vdc) Outputs 15 4.2 3.4 8.8 2.4 OH (V = 0.4 Vdc) Sink I 5.0 0.5 0.4 0.88 0.28 mAdc OL OL (V = 0.5 Vdc) Pin 3 10 1.1 0.9 2.25 0.65 OL (V = 1.5 Vdc) 15 1.8 1.5 8.8 1.20 OL (V = 0.4 Vdc) Sink Other 5.0 3.0 2.5 4.0 1.6 mAdc OL (V = 0.5 Vdc) Outputs 10 6.0 5.0 8.0 3.5 OL (V = 1.5 Vdc) 15 18 15 20 10 OL Input Current I 15 0.1 0.00001 0.1 1.0 Adc in Input Capacitance (V = 0) C 5.0 7.5 pF in in Quiescent Current (Per Package) I 5.0 5.0 0.010 5.0 150 Adc DD MR = V 10 10 0.020 10 300 DD 15 20 0.030 20 600 Total Supply Current (Note 3, 4) I 5.0 I = (0.35 A/kHz) f + I Adc T T DD (Dynamic plus Quiescent, Per Package) 10 I = (0.85 A/kHz) f + I T DD (C = 50 pF on all outputs, all buffers switching) 15 I = (1.50 A/kHz) f + I L T DD 2. Data labelled Typ is not to be used for design purposes but is intended as an indication of the ICs potential performance. 3. The formulas given are for the typical characteristics only at 25 C. 4. To calculate total supply current at loads other than 50 pF: I (C ) = I (50 pF) + (C 50) Vfk where: I is in A (per package), C in pF, T L T L T L V = (V V ) in volts, f in kHz is input frequency, and k = 0.004. DD SS