74HC299 Datasheet, PDF (16/24 Pages) NXP Semiconductors – 8-bit universal shift register; 3-state

NXP Semiconductors
74HC299; 74HCT299
8-bit universal shift register; 3-state
t_r
V_I
90 %
OEn input
V_M
GND10 ^%
t_PLZ
V_OH
I/On output
LOW to OFF
OFF to LOW
V_OL
10 %
t_PHZ
V_OH
I/On output
HIGH to OFF
OFF to HIGH
V_OL
90 %
outputs
enabled
t_f
t_PZL
V_M
t_PZH
outputs
disabled
V_M
outputs
enabled
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Measurement points are given in Table 8.
V_OL and V_OH are typical voltage output levels that occur with the output load.
Fig 10. 3-state enable and disable times for OEn inputs
Table 8. Measurement points
Type
Input
V_I
74HC299
V_CC
74HCT299
3V
V_M
0.5V_CC
1.3 V
Output
V_M
0.5V_CC
1.3 V
V_CC
V_CC
PULSE
VI
GENERATOR
VO
DUT
RT
RL = 1 kΩ S1
CL
50 pF
open
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Test data is given in Table 9.
Definitions for test circuit:
DUT = Device Under Test.
R_T = Termination resistance should be equal to output impedance Z_o of the pulse generator.
C_L = Load capacitance including jig and probe capacitance.
R_L = Load resistance.
S1 = Test selection switch
Fig 11. Test circuit for measuring switching times
74HC_HCT299_3
Product data sheet
Rev. 03 — 28 July 2008
© NXP B.V. 2008. All rights reserved.
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