74HC_HCT4538_15 Datasheet, PDF (12/24 Pages) NXP Semiconductors – Dual retriggerable precision monostable multivibrator

NXP Semiconductors
74HC4538; 74HCT4538
Dual retriggerable precision monostable multivibrator
Table 7. Dynamic characteristics …continued
Voltages are referenced to GND (ground = 0 V); for test circuit see Figure 9.
Symbol Parameter Conditions
25 °C
Min Typ^[1] Max
C_PD
power
per multivibrator;
[3]
-
138
-
dissipation
V_I = GND to (V_CC − 1.5 V)
capacitance
−40 °C to
+85 °C
Min Max
-
-
−40 °C to Unit
+125 °C
Min Max
-
- pF
[1] Typical values are measured at nominal supply voltage (V_CC = 3.3 V and V_CC = 5.0 V).
[2] t_t is the same as t_THL and t_TLH.
[3] C_PD is used to determine the dynamic power dissipation (P_D in µW).
P_D = C_PD × V_CC2 × f_i × Σ(C_L × V_CC2 × f_o) + 0.48 × C_EXT × V_CC2 × f_o + D × 0.8 × V_CC where:
f_i = input frequency in MHz;
f_o = output frequency in MHz;
Σ(C_L × V_CC2 × f_o) = sum of the outputs;
C_L = output load capacitance in pF;
V_CC = supply voltage in V;
D = duty cycle factor in %;
C_EXT = external timing capacitance in pF.
11. Waveforms
V_I
nB input
GND
V_I
nA input
GND
V_I
nCD input
GND
V_OH
nQ output
V_OL
V_OH
nQ output
V_OL
V_M
t_W
t_PLH
V_M
t_PHL
V_M
V_M
t_W
V_Y
V_X
t_THL
t_PLH
V_M
t_PHL
t_TLH
V_Y
V_X
Fig 7.
Measurement points are given in Table 8.
Logic levels: V_OL and V_OH are typical output levels that occur with the output load.
Waveforms showing propagation delays and transition times
V_M
t_PHL
t_PLH
001aak194
74HC_HCT4538_3
Product data sheet
Rev. 03 — 8 June 2009
© NXP B.V. 2009. All rights reserved.
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