ST1284-xxA8/T8
TECHNICAL INFORMATION
FREQUENCY BEHAVIOR OF DATA AND STROBE SIGNALS
Fig. A1: Measurement conditions
Fig. A2: Typical frequency response curve for data
and strobe signals.
TRACKING
GENERATOR
50Ω
Vg
+5V
SPECTRUM
ANALYSER
ST1284
50Ω
Vin
Vout
0.00
dB
- 5.00
- 10.00
- 15.00
- 20.00
- 25.00
- 30.00
1
3
1284 - 01
1284 - 03
10
30
100
300
1,000
F (MHz) 1284 - 02
ESD PROTECTION
In addition to the requirements of termination and EMC compatibility, computing devices are required to be
tested for ESD susceptibility. This test is described in the IEC61000-4-2 and is already in place in Europe.
This test requires that a device tolerates ESD events and remain operational without user intervention.
The ST1284-xxA8/T8 is particularly optimized to perform ESD protection. ESD protection is based on the
use of device which clamps at :
Vouput = VBR + Rd.IPP
This protection function is splitted in 2 stages. As shown in figure A3, the ESD strikes are clamped by the
first stage S1 and then its remaining overvoltage is applied to the second stage through the resistor R.
Such a configuration makes the voltage very low at the output.
Fig. A3: ST1284 ESD clamping behavior
Rg
S1
R
S2
VPP
ESD Surge
Rd
Vinput
Rd
VBR
Voutput
VBR
ST1284-xxA8/T8
Rload
Device
to be
protected
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