MC14521B 24-Stage Frequency Divider The MC14521B consists of a chain of 24 flip–flops with an input circuit that allows three modes of operation. The input will function as a crystal oscillator, an RC oscillator, or as an input buffer for an external oscillator. Each flip–flop divides the frequency of the previous flip–flop by two, consequently this part will count up to 224 = 16,777,216. The count advances on the negative going edge of the clock. The outputs of the last seven–stages are available for added flexibility. http://onsemi.com MARKING DIAGRAMS • All Stages are Resettable • Reset Disables the RC Oscillator for Low Standby Power Drain • RC and Crystal Oscillator Outputs Are Capable of Driving External • • • • 16 PDIP–16 P SUFFIX CASE 648 Loads Test Mode to Reduce Test Time VDD′ and VSS′ Pins Brought Out on Crystal Oscillator Inverter to Allow the Connection of External Resistors for Low–Power Operation Supply Voltage Range = 3.0 Vdc to 18 Vdc Capable of Driving Two Low–power TTL Loads or One Low–power Schottky TTL Load over the Rated Temperature Range. 1 16 SOIC–16 D SUFFIX CASE 751B VDD Vin, Vout Iin, Iout PD Parameter 16 SOEIAJ–16 F SUFFIX CASE 966 Unit – 0.5 to +18.0 V – 0.5 to VDD + 0.5 V Input or Output Current (DC or Transient) per Pin ± 10 mA Power Dissipation, per Package (Note 3.) 500 mW Input or Output Voltage Range (DC or Transient) TA Ambient Temperature Range – 55 to +125 °C Tstg Storage Temperature Range – 65 to +150 °C TL Lead Temperature (8–Second Soldering) 260 °C 2. Maximum Ratings are those values beyond which damage to the device may occur. 3. Temperature Derating: Plastic “P and D/DW” Packages: – 7.0 mW/_C From 65_C To 125_C This device contains protection circuitry to guard against damage due to high static voltages or electric fields. However, precautions must be taken to avoid applications of any voltage higher than maximum rated voltages to this high–impedance circuit. For proper operation, Vin and Vout should be constrained (Vin or Vout) VDD. to the range VSS Unused inputs must always be tied to an appropriate logic voltage level (e.g., either VSS or VDD). Unused outputs must be left open. v A = Assembly Location WL or L = Wafer Lot YY or Y = Year WW or W = Work Week ORDERING INFORMATION Device Package Shipping MC14521BCP PDIP–16 2000/Box MC14521BD SOIC–16 48/Rail MC14521BDR2 SOIC–16 2500/Tape & Reel MC14521BF SOEIAJ–16 See Note 1. MC14521BFEL SOEIAJ–16 See Note 1. MC14521BFR2 SOEIAJ–16 See Note 1. 1. For ordering information on the EIAJ version of the SOIC packages, please contact your local ON Semiconductor representative. v Semiconductor Components Industries, LLC, 2000 March, 2000 – Rev. 3 MC14521B AWLYWW 1 Value DC Supply Voltage Range 14521B AWLYWW 1 MAXIMUM RATINGS (Voltages Referenced to VSS) (Note 2.) Symbol MC14521BCP AWLYYWW 1 Publication Order Number: MC14521B/D MC14521B PIN ASSIGNMENT VDD Q24 1 16 RESET 2 15 Q23 VSS′ 3 14 Q22 OUT 2 4 13 Q21 VDD′ 5 12 Q20 IN 2 6 11 Q19 7 10 Q18 8 9 IN 1 VSS BLOCK DIAGRAM RESET 2 9 IN 1 STAGES 1 THRU 17 6 IN 2 7 OUT 1 5 VDD′ 3 VSS′ 4 OUT2 STAGES 18 THRU 24 Q18 Q19 Q20 Q21 Q22 Q23 Q24 VDD = PIN 16 VSS = PIN 8 10 11 12 13 14 http://onsemi.com 2 15 1 Output Count Capacity Q18 Q19 Q20 Q21 Q22 Q23 Q24 218 = 262,144 219 = 524,288 220 = 1,048,576 221 = 2,097,152 222 = 4,194,304 223 = 8,388,608 224 = 16,777,216 MC14521B ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ELECTRICAL CHARACTERISTICS (Voltages Referenced to VSS) Characteristic Symbol Output Voltage Vin = VDD or 0 – 55_C 25_C 125_C VDD Vdc Min Max Min Typ (4.) Max Min Max Unit “0” Level VOL 5.0 10 15 — — — 0.05 0.05 0.05 — — — 0 0 0 0.05 0.05 0.05 — — — 0.05 0.05 0.05 Vdc “1” Level VOH 5.0 10 15 4.95 9.95 14.95 — — — 4.95 9.95 14.95 5.0 10 15 — — — 4.95 9.95 14.95 — — — Vdc Input Voltage “0” Level (VO = 4.5 or 0.5 Vdc) (VO = 9.0 or 1.0 Vdc) (VO = 13.5 or 1.5 Vdc) VIL 5.0 10 15 — — — 1.5 3.0 4.0 — — — 2.25 4.50 6.75 1.5 3.0 4.0 — — — 1.5 3.0 4.0 “1” Level VIH 5.0 10 15 3.5 7.0 11 — — — 3.5 7.0 11 2.75 5.50 8.25 — — — 3.5 7.0 11 — — — Source Pins 4 & 7 5.0 5.0 10 15 – 1.2 – 0.25 – 0.62 – 1.8 — — — — – 1.0 – 0.2 – 0.5 – 1.5 – 1.7 – 0.36 – 0.9 – 3.5 — — — — – 0.7 – 0.14 – 0.35 – 1.1 — — — — (VOH = 2.5 Vdc) Source (VOH = 4.6 Vdc) Pins 1, 10, (VOH = 9.5 Vdc) 11, 12, 13, 14 (VOH = 13.5 Vdc) and 15 5.0 5.0 10 15 – 3.0 – 0.64 – 1.6 – 4.2 — — — — – 2.4 – 0.51 – 1.3 – 3.4 – 4.2 – 0.88 – 2.25 – 8.8 — — — — – 1.7 – 0.36 – 0.9 – 2.4 — — — — mAdc IOL 5.0 10 15 0.64 1.6 4.2 — — — 0.51 1.3 3.4 0.88 2.25 8.8 — — — 0.36 0.9 2.4 — — — mAdc Input Current Iin 15 — ± 0.1 — ± 0.00001 ± 0.1 — ± 1.0 µAdc Input Capacitance (Vin = 0) Cin — — — — 5.0 7.5 — — pF Quiescent Current (Per Package) IDD 5.0 10 15 — — — 5.0 10 20 — — — 0.005 0.010 0.015 5.0 10 20 — — — 150 300 600 µAdc IT 5.0 10 15 Vin = 0 or VDD (VO = 0.5 or 4.5 Vdc) (VO = 1.0 or 9.0 Vdc) (VO = 1.5 or 13.5 Vdc) Output Drive Current (VOH = 2.5 Vdc) (VOH = 4.6 Vdc) (VOH = 9.5 Vdc) (VOH = 13.5 Vdc) (VOL = 0.4 Vdc) (VOL = 0.5 Vdc) (VOL = 1.5 Vdc) Vdc Vdc IOH Sink Total Supply Current (5.) (6.) (Dynamic plus Quiescent, Per Package) (CL = 50 pF on all outputs, all buffers switching) mAdc IT = (0.42 µA/kHz) f + IDD IT = (0.85 µA/kHz) f + IDD IT = (1.40 µA/kHz) f + IDD 4. Data labelled “Typ” is not to be used for design purposes but is intended as an indication of the IC’s potential performance. 5. The formulas given are for the typical characteristics only at 25_C. 6. To calculate total supply current at loads other than 50 pF: IT(CL) = IT(50 pF) + (CL – 50) Vfk where: IT is in µA (per package), CL in pF, V = (VDD – VSS) in volts, f in kHz is input frequency, and k = 0.003. http://onsemi.com 3 µAdc MC14521B ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ SWITCHING CHARACTERISTICS (7.) (CL = 50 pF, TA = 25_C) Characteristic Symbol Output Rise and Fall Time (Counter Outputs) tTLH, tTHL = (1.5 ns/pF) CL + 25 ns tTLH, tTHL = (0.75 ns/pF) CL + 12.5 ns tTLH, tTHL = (0.55 ns/pF) CL + 12.5 ns tTLH, tTHL Propagation Delay Time Clock to Q18 tPHL, tPLH = (1.7 ns/pF) CL + 4415 ns tPHL, tPLH = (0.66 ns/pF) CL + 1667 ns tPHL, tPLH = (0.5 ns/pF) CL + 1275 ns tPHL, tPLH Min Typ (8.) Max 5.0 10 15 — — — 100 50 40 200 100 80 Unit ns µs Clock to Q24 tPHL, tPLH = (1.7 ns/pF) CL + 5915 ns tPHL, tPLH = (0.66 ns/pF) CL + 2167 ns tPHL, tPLH = (0.5 ns/pF) CL + 1675 ns Propagation Delay Time Reset to Qn tPHL = (1.7 ns/pF) CL + 1215 ns tPHL = (0.66 ns/pF) CL + 467 ns tPHL = (0.5 ns/pF) CL + 350 ns VDD Vdc 5.0 10 15 — — — 4.5 1.7 1.3 9.0 3.5 2.7 5.0 10 15 — — — 6.0 2.2 1.7 12 4.5 3.5 tPHL 5.0 10 15 — — — 1300 500 375 2600 1000 750 tWH(cl) 5.0 10 15 385 150 120 140 55 40 — — — ns fcl 5.0 10 15 — — — 3.5 9.0 12 2.0 5.0 6.5 MHz tTLH, tTHL 5.0 10 15 — — — — — — 15 5.0 4.0 µs tWH(R) 5.0 10 15 1400 600 450 700 300 225 — — — ns trem 5.0 10 15 30 0 – 40 – 200 – 160 – 110 — — — ns Clock Pulse Width Clock Pulse Frequency Clock Rise and Fall Time ns Reset Pulse Width Reset Removal Time 7. The formulas given are for the typical characteristics only at 25_C. 8. Data labelled “Typ” is not to be used for design purposes but is intended as an indication of the IC’s potential performance. VDD 500 µF VDD PULSE GENERATOR 0.01 µF CERAMIC ID IN 2 R VSS VDD Q18 Q19 Q20 Q21 Q22 Q23 Q24 CL CL Vin CL 20 ns 90% 50% 10% 50% DUTY CYCLE CL CL CL CL VSS Figure 1. Power Dissipation Test Circuit and Waveform http://onsemi.com 4 20 ns VDD 0V MC14521B VDD VDD′ VDD PULSE GENERATOR IN 2 R 20 ns CL CL tWL CL CL Qn CL 50% 20 ns 90% 50% 10% CL VSS′ VSS 20 ns IN 2 Q18 Q19 Q20 Q21 Q22 Q23 Q24 tWH 90% 10% tPLH tTLH CL tPHL tTHL Figure 2. Switching Time Test Circuit and Waveforms 500 kHz Circuit 50 kHz Circuit Unit Crystal Characteristics Resonant Frequency Equivalent Resistance, RS 500 1.0 50 6.2 kHz kΩ External Resistor/Capacitor Values Ro CT CS 47 82 20 750 82 20 kΩ pF pF + 6.0 + 2.0 + 2.0 + 2.0 ppm ppm – 4.0 + 100 – 2.0 + 120 ppm ppm – 2.0 – 160 – 2.0 – 560 ppm ppm Characteristic VDD Ro 18 M CS CT VDD R* VDD′ IN 1 OUT 1 OUT 2 Q18 Q19 IN 2 Q20 Q21 Q22 Q23 R Q24 VSS VSS′ R* * Optional for low power operation, 10 kΩ ≤ R ≤ 70 kΩ. Figure 3. Crystal Oscillator Circuit Frequency Stability Frequency Change as a Function of VDD (TA = 25_C) VDD Change from 5.0 V to 10 V VDD Change from 10 V to 15 V Frequency Change as a Function of Temperature (VDD = 10 V) TA Change from – 55_C to + 25_C MC14521 only Complete Oscillator* TA Change from + 25_C to + 125_C MC14521 only Complete Oscillator* ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ *Complete oscillator includes crystal, capacitors, and resistors. Figure 4. Typical Data for Crystal Oscillator Circuit http://onsemi.com 5 MC14521B f, OSCILLATOR FREQUENCY (kHz) 100 8.0 FREQUENCY DEVIATION (%) VDD = 15 V 4.0 TEST CIRCUIT FIGURE 7 0 10 V –4.0 –8.0 5.0 V 20 f AS A FUNCTION OF RTC (C = 1000 pF) (RS ≈ 2RTC) 10 5.0 2.0 1.0 TEST CIRCUIT FIGURE 7 VDD = 10 V 50 f AS A FUNCTION OF C (RTC = 56 kΩ) (RS = 120 k) 0.5 0.2 –12 RTC = 56 kΩ, C = 1000 pF –16 –55 0.1 RS = 0, f = 10.15 kHz @ VDD = 10 V, TA = 25°C RS = 120 kΩ, f = 7.8 kHz @ VDD = 10 V, TA = 25°C { –25 0 25 50 75 100 TA, AMBIENT TEMPERATURE (°C), DEVICE ONLY 1.0 k 125 0.0001 Figure 5. RC Oscillator Stability RS RTC 10 k 100 k RTC, RESISTANCE (OHMS) 0.001 0.01 C, CAPACITANCE (µF) 1.0 m 0.1 Figure 6. RC Oscillator Frequency as a Function of RTC and C VDD VDD C VDD VDD′ VDD′ IN 1 IN 1 IN 2 R OUT 1 OUT 2 Q18 Q19 Q20 Q21 Q22 Q23 Q24 VSS PULSE GENERATOR Q18 Q19 Q20 Q21 IN 2 Q22 Q23 Q24 OUT 1 R OUT 2 VSS VSS′ Figure 7. RC Oscillator Circuit VSS Figure 8. Functional Test Circuit http://onsemi.com 6 MC14521B ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ FUNCTIONAL TEST SEQUENCE Inputs A test function (see Figure 8) has been included for the reduction of test time required to exercise all 24 counter stages. This test function divides the counter into three 8–stage sections, and 255 counts are loaded in each of the 8–stage sections in parallel. All flip–flops are now at a logic g “1”. The counter is now returned to the normal 24–stages in series configuration. One more pulse is entered into Input 2 (In 2) which will cause the counter to ripple from an all “1” state to an all “0” state. Outputs Comments Reset In 2 Out 2 VSS′ VDD′ Q18 thru Q24 1 0 0 VDD Gnd 0 0 1 1 First “0” to “1” transition on In 2, Out 2 node. 0 1 — — — 0 1 — — — 255 “0” to “1” transitions are clocked into this In 2, Out 2 node. 1 1 1 0 0 0 0 1 1 1 0 1 0 G d Gnd The 255th “0” to “1” transition. 1 Counter converted back to 24–stages in series mode. 0 1 Out 2 converts back to an output. 1 0 http://onsemi.com 7 Counter is in three 8–stage sections in parallel mode Counter is reset. In 2 and Out 2 are connected together VDD Counter ripples from an all “1” state to an all “0” stage. MC14521B LOGIC DIAGRAM VDD 5 RESET 2 9 1 2 IN 1 3 VSS 9 17 18 19 10 Q18 8 4 OUT 2 6 IN 2 7 OUT 1 STAGES 3 THRU 7 20 11 Q19 21 12 Q20 22 10 23 13 Q21 14 Q22 16 24 15 Q23 http://onsemi.com 8 STAGES 11 THRU 15 1 Q24 VDD = PIN 16 VSS = PIN 8 MC14521B PACKAGE DIMENSIONS PDIP–16 P SUFFIX PLASTIC DIP PACKAGE CASE 648–08 ISSUE R –A– 16 9 1 8 NOTES: 1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982. 2. CONTROLLING DIMENSION: INCH. 3. DIMENSION L TO CENTER OF LEADS WHEN FORMED PARALLEL. 4. DIMENSION B DOES NOT INCLUDE MOLD FLASH. 5. ROUNDED CORNERS OPTIONAL. B F C L S –T– SEATING PLANE K H G D M J 16 PL 0.25 (0.010) M T A M http://onsemi.com 9 DIM A B C D F G H J K L M S INCHES MIN MAX 0.740 0.770 0.250 0.270 0.145 0.175 0.015 0.021 0.040 0.70 0.100 BSC 0.050 BSC 0.008 0.015 0.110 0.130 0.295 0.305 0_ 10 _ 0.020 0.040 MILLIMETERS MIN MAX 18.80 19.55 6.35 6.85 3.69 4.44 0.39 0.53 1.02 1.77 2.54 BSC 1.27 BSC 0.21 0.38 2.80 3.30 7.50 7.74 0_ 10 _ 0.51 1.01 MC14521B PACKAGE DIMENSIONS SOIC–16 D SUFFIX PLASTIC SOIC PACKAGE CASE 751B–05 ISSUE J –A– 16 NOTES: 1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982. 2. CONTROLLING DIMENSION: MILLIMETER. 3. DIMENSIONS A AND B DO NOT INCLUDE MOLD PROTRUSION. 4. MAXIMUM MOLD PROTRUSION 0.15 (0.006) PER SIDE. 5. DIMENSION D DOES NOT INCLUDE DAMBAR PROTRUSION. ALLOWABLE DAMBAR PROTRUSION SHALL BE 0.127 (0.005) TOTAL IN EXCESS OF THE D DIMENSION AT MAXIMUM MATERIAL CONDITION. 9 –B– 1 P 8 PL 0.25 (0.010) 8 M B S G R K F X 45 _ C –T– SEATING PLANE J M D 16 PL 0.25 (0.010) M T B S A S http://onsemi.com 10 DIM A B C D F G J K M P R MILLIMETERS MIN MAX 9.80 10.00 3.80 4.00 1.35 1.75 0.35 0.49 0.40 1.25 1.27 BSC 0.19 0.25 0.10 0.25 0_ 7_ 5.80 6.20 0.25 0.50 INCHES MIN MAX 0.386 0.393 0.150 0.157 0.054 0.068 0.014 0.019 0.016 0.049 0.050 BSC 0.008 0.009 0.004 0.009 0_ 7_ 0.229 0.244 0.010 0.019 MC14521B PACKAGE DIMENSIONS SOEIAJ–16 F SUFFIX PLASTIC EIAJ SOIC PACKAGE CASE 966–01 ISSUE O 16 LE 9 Q1 M_ E HE 1 L 8 DETAIL P Z D e VIEW P A A1 b 0.13 (0.005) c M 0.10 (0.004) http://onsemi.com 11 NOTES: 1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982. 2. CONTROLLING DIMENSION: MILLIMETER. 3. DIMENSIONS D AND E DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS AND ARE MEASURED AT THE PARTING LINE. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.15 (0.006) PER SIDE. 4. TERMINAL NUMBERS ARE SHOWN FOR REFERENCE ONLY. 5. THE LEAD WIDTH DIMENSION (b) DOES NOT INCLUDE DAMBAR PROTRUSION. ALLOWABLE DAMBAR PROTRUSION SHALL BE 0.08 (0.003) TOTAL IN EXCESS OF THE LEAD WIDTH DIMENSION AT MAXIMUM MATERIAL CONDITION. DAMBAR CANNOT BE LOCATED ON THE LOWER RADIUS OR THE FOOT. MINIMUM SPACE BETWEEN PROTRUSIONS AND ADJACENT LEAD TO BE 0.46 ( 0.018). DIM A A1 b c D E e HE L LE M Q1 Z MILLIMETERS MIN MAX ––– 2.05 0.05 0.20 0.35 0.50 0.18 0.27 9.90 10.50 5.10 5.45 1.27 BSC 7.40 8.20 0.50 0.85 1.10 1.50 10 _ 0_ 0.70 0.90 ––– 0.78 INCHES MIN MAX ––– 0.081 0.002 0.008 0.014 0.020 0.007 0.011 0.390 0.413 0.201 0.215 0.050 BSC 0.291 0.323 0.020 0.033 0.043 0.059 10 _ 0_ 0.028 0.035 ––– 0.031 MC14521B ON Semiconductor and are trademarks of Semiconductor Components Industries, LLC (SCILLC). SCILLC reserves the right to make changes without further notice to any products herein. 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