Datasheet

PIN FUNCTIONS
SO20L Power DIP Name Description
11
SIGNAL SUPPLY VOLTAGE Must be Connected to pin 3
22
OUTPUT Regulator output
33
SUPPLY VOLTAGE
Unregulated voltage input. An internal regulator
powers the internal logic.
4, 5, 6, 7
14, 15, 16, 17
4, 5, 6
13, 14, 15
GROUND Common ground terminal
87
POWER FAIL INPUT
Input of the power fail circuit. The threshold can be
modified introducing an external voltage divider
between the Supply Voltage and GND.
98
POWER FAIL OUTPUT
Open collector power fail signal output. This output
is high when the supply voltage is safe.
10 9
RESET DELAY
A capacitor connected between this terminal and
ground determines the reset signal delay time.
11 10
RESET OUTPUT
Open collector reset signal output. This output is
high when the output voltage value is correct.
12 11
REFERENCE VOLTAGE Reference voltage output.
13 12
FEEDBACK INPUT
Feedback terminal of the regulation loop.
The output is connected directly to this terminal for
5.1V operation; it is connected via a divider for
higher voltages.
18 16
INHIBIT INPUT
TTL level remote inhibit. A logic low level on this
input disables the device.
19 17
C OSCILLATOR
Oscillator waveform. A capacitor connected
between this terminal and ground modifies the
maximum oscillator frequency.
20 18
R OSCILLATOR FREQ.
A resistor connected between this terminal and
ground defines the maximum switching frequency.
THERMAL DATA
Symbol Parameter SO20 Powerdip Unit
R
th j-pins
Thermal Resistance Junction to Pins max.
15 12
°
C/W
R
th j-amb
Thermal Resistance Junction to Ambient (*) max.
85 80
°
C/W
(*) See Fig. 28
L4963 - L4963D
3/17