TOP232-234
BENCH TEST PRECAUTIONS FOR EVALUATION OF ELECTRICAL CHARACTERISTICS
restart mode, there is only a 12.5% chance that the CONTROL
pin oscillation will be in the correct state (drain active state) so
that the continuous drain voltage waveform may be observed.
It is recommended that the VC power supply be turned on first
and the DRAIN pin power supply second if continuous drain
voltage waveforms are to be observed. The 12.5% chance of
being in the correct state is due to the divide-by-8 counter.
Temporarily shorting the CONTROL pin to the SOURCE pin
will reset TOPSwitch-FX, which then will come up in the
correct state.
The following precautions should be followed when testing
TOPSwitch-FXbyitselfoutsideofapowersupply.Theschematic
shown in Figure 34 is suggested for laboratory testing of
TOPSwitch-FX.
When the DRAIN pin supply is turned on, the part will be in the
auto-restartmode. TheCONTROLpinvoltagewillbeoscillating
at a low frequency between 4.8 and 5.8 V and the drain is turned
on every eighth cycle of the CONTROL pin oscillation. If the
CONTROL pin power supply is turned on while in this auto-
Typical Performance Characteristics
CURRENT LIMIT vs. MULTI-FUNCTION
PIN CURRENT
PI-2540-033001
200
180
160
140
120
100
1.0
.9
.8
.7
.6
Scaling Factors:
.5
.4
TOP234 1.50
TOP233 1.00
TOP232 0.50
80
60
.3
-250
-200
-150
-100
-50
0
IM (µA)
CURRENT LIMIT vs. EXTERNAL
CURRENT LIMIT RESISTANCE
PI-2539-033001
1.1
1.0
200
Scaling Factors:
TOP234 1.50
TOP233 1.00
TOP232 0.50
.9
.8
.7
.6
180
160
140
120
Maximum
Minimum
Typical
.5
.4
.3
100
80
Maximum and minimum levels
are based on characterization.
60
0
5K
10K
15K
20K
25K
30K
External Current Limit Resistor RIL (Ω)
B
7/01
30
ETC [ ETC ]
