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2-214
Functional Pin Descriptions
VSEN1 (Pin 22)
This pin is connected to the PWM converter’s output voltage.
The PGOOD and OVP comparator circuits use this signal to
report output voltage status and for over-voltage protection.
OCSET1 (Pin 23)
Connect a resistor (R
OCSET
) from this pin to the drain of the
respective upper MOSFET. R
OCSET
, an internal 200
μ
A
current source (I
OCSET
), and the upper MOSFET on-
resistance (r
DS(ON)
) set the converter over-current (OC) trip
point according to the following equation:
An over-current trip cycles the soft-start function. Sustaining
an over-current for 2 soft-start intervals shuts down the IC.
Additionally, OCSET1 is an output for the inverted FAULT
signal (FAULT). If a fault condition causes FAULT to go high,
OCSET1 will be simultaneously pulled to ground though an
internal MOS device (typical r
DS(ON)
= 100
).
Slew Rate
SR
COMP = 10pF
-
6
-
V/
μ
s
PWM CONTROLLER GATE DRIVER
Upper Drive Source
I
UGATE
R
UGATE
I
LGATE
R
LGATE
VCC = 12V, V
UGATE1
= 6V
V
UGATE1-PHASE1
= 1V
VCC = 12V, V
LGATE1
= 1V
V
LGATE1
= 1V
-
1
-
A
Upper Drive Sink
-
1.7
3.5
Lower Drive Source
-
1
-
A
Lower Drive Sink
-
1.4
3.0
PROTECTION
V
OUT1
Over-Voltage Trip
FAULT Sourcing Current
VSEN1 Rising
112
115
118
%
I
OVP
I
OCSET
I
SS
V
FAULT/RT
= 10V
V
OCSET
= 4.5V
DC
10
14
-
mA
OCSET1 Current Source
170
200
230
μ
A
Soft-Start Current
-
11
-
μ
A
Chip Shutdown Soft-Start Threshold
-
-
1.0
V
POWER GOOD
V
OUT1
Upper Threshold
V
OUT1
Under-Voltage (Lower Threshold)
V
OUT1
Hysteresis (VSEN1/DACOUT)
PGOOD Voltage Low
VSEN1 Rising
108
-
110
%
VSEN1 Rising
92
-
94
%
Upper/Lower Threshold
-
2
-
%
V
PGOOD
I
PGOOD
= -4mA
-
-
0.5
V
Electrical Specifications
Recommended Operating Conditions, Unless Otherwise Noted. Refer to Figures 1, 2 and 3
(Continued)
PARAMETER
SYMBOL
TEST CONDITIONS
MIN
TYP
MAX
UNITS
Typical Performance Curves
FIGURE 4. R
T
RESISTANCE vs FREQUENCY
FIGURE 5. BIAS SUPPLY CURRENT vs FREQUENCY
10
100
1000
SWITCHING FREQUENCY (kHz)
R
)
10
100
1000
R
T
PULLUP
TO +12V
R
T
PULLDOWN TO V
SS
100
200
300
400
500
600
700
800
900 1000
0
20
40
60
80
100
SWITCHING FREQUENCY (kHz)
I
C
C
UGATE1
= C
LGATE1
= C
GATE
V
VCC
= 12V, V
IN
= 5V
C
GATE
= 4800pF
C
GATE
= 3600pF
C
GATE
= 1500pF
C
GATE
= 660pF
I
PEAK
I
xR
DS ON
)
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=
HIP6017