Datasheet 74HC14, 74HCT14 (Nexperia) - 9

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Nexperia 74HC14; 74HCT14 Hex inverting Schmitt trigger 13. Application information
The slow input rise and fall times cause additional power dissipation, this can be calculated using the following formula: Padd = fi × (tr × ΔICC(AV) + tf × ΔICC(AV)) × VCC where: • Padd = additional power dissipation (μW); • fi = input frequency (MHz); • tr = rise time (ns); 10 % to 90 %; • tf = fall time (ns); 90 % to 10 %; • ΔICC(AV) = average additional supply current (μA). Average ΔICC(AV) dif ers with positive or negative input transitions, as shown in Fig. 10 and Fig. 11. An example of a relaxation circuit using the 74HC14; 74HCT14 is shown in Fig. 12. 400 mna852 400 mna853 ICC(AV) ICC(AV) (µA) (µA) 300 300 positive - going edge 200 positive - going 200 edge negative - going 100 100 edge negative - going edge 0 0 0 2 4 V 6 CC (V) 0 2 4 V 6 CC (V)
Fig. 10. Average additional supply current Fig. 11. Average additional supply current as a function of VCC for 74HC14; as a function of VCC for 74HCT14; linear change of VI between 0.1VCC to 0.9VCC. linear change of VI between 0.1VCC to 0.9VCC.
R C mna035 For 74HC14 and 74HCT14: For K-factor see Fig. 13
Fig. 12. Relaxation oscillator
74HC_HCT14 All information provided in this document is subject to legal disclaimers. © Nexperia B.V. 2024. Al rights reserved
Product data sheet Rev. 10 — 29 February 2024 9 / 16
Document Outline 1. General description 2. Features and benefits 3. Applications 4. Ordering information 5. Functional diagram 6. Pinning information 6.1. Pinning 6.2. Pin description 7. Functional description 8. Limiting values 9. Recommended operating conditions 10. Static characteristics 11. Dynamic characteristics 11.1. Waveforms and test circuit 12. Transfer characteristics 12.1. Transfer characteristics waveforms 13. Application information 14. Package outline 15. Abbreviations 16. Revision history 17. Legal information Contents