Package Pin Description
PIN SYMBOL
PACKAGE PIN #
FUNCTION
16L
SO Wide
5L
TO-220
8L
PDIP
16
3
1
2
1
Gnd
VC
Logic and power ground on TO-220. Logic ground only on 8L
PDIP.
2
2
Control voltage can be used for frequency compensation, cur-
rent limit threshold, frequency synchronization, and soft start.
3
3
4
VFB
NC
Feedback voltage is the negative input to the error amplifier.
No connection.
1,4,5,6,7,8,
10,12,15
9
5
4
5
6
VIN
E1
Supply input voltage with a range of 3V to 60V.
11
Emitter One is a power ground which should always be con-
nected to logic ground since it is used as the negative input to
the current sense amp.
13
14
7
8
VSW
E2
Collector of internal 75V NPN power switch.
Emitter Two is a power ground which can be left disconnected
to reduce the switch rating to 625mA.
Typical Performance Characteristics
Switching Frequency vs. Temperature
Reference Voltage vs. Temperature
Driver Current vs. Switch Current
47
45
100
1.274
90
1.264
1.254
1.244
1.234
1.224
1.214
80
70
60
50
40
43
41
39
37
35
33
30
20
10
0
-50
-25
-0
25
50
75
100 125
150
-50
-25
-0
25
50
75
100 125
150
0
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
Temperature (°C)
Temperature (°C)
Switch Current (A)
Switch Saturation Voltage
Maximum Duty Cycle
1.6
97
T =25°C
j
1.4
1.2
1.0
96
95
93
92
0.8
0.6
0.4
0.2
0
91
90
0
0.25 0.50 0.75 1.00 1.25 1.50 1.75
2.0
-50
-25
-0
25
50
75
100 125
150
Switch Current (A)
Junction Temperature (°C)
3
CHERRY [ CHERRY SEMICONDUCTOR CORPORATION ]
