Datasheet
September 1993 6
Philips Semiconductors Product specification
Hex inverter 74HCU04
Fig.10 Test set-up for measuring forward
transconductance g
fs
=di
o
/dv
i
at v
o
is constant
(see also graph Fig.11).
Fig.11 Typical forward transconductance g
fs
as a
function of the supply voltage V
CC
at
T
amb
=25°C.
APPLICATION INFORMATION
Some applications for the “HCU04” are:
• Linear amplifier (see Fig.12)
• In crystal oscillator designs (see Fig.13)
• Astable multivibrator (see Fig.14)
Fig.12 HCU04 used as a linear amplifier.
Z
L
> 10 kΩ; A
OL
= 20 (typ.)
V
O max (p-p)
≈ V
CC
−2 V centered at
1
⁄
2
V
CC
3kΩ≤ R1, R2 ≤ 1 MΩ
Typical unity gain bandwidth product is 5 MHz.
C
I
(see Fig.15)
A
OL
= open loop amplification
A
u
= voltage amplification
A
u
A
OL
1
R1
R2
--------
1A
OL
+()+
---------------------------------------------
;–=