Voltage Regulators
AN8049SH
I Terminal Equivalent Circuits (continued)
Pin No.
Equivalent circuit
4
9 24 17
45 kΩ
PWM1
4 55 kΩ
5
VCC
20 kΩ 1.1 µA
High
Channel 3
1.26 V output operation
5
6
VCC
20 kΩ 1.1 µA
High
Channel 2
1.26 V output operation
6
Description
I/O
DT1:
I
Sets the channel 1 soft start time.
Set the time by connecting a capacitor between
this pin and ground.
(See the "Application Notes, [7]" section.)
Note that although the channel 1 maximum on
duty is set internally to 86%, the maximum on
duty can be adjusted by connecting resistors
between this pin and ground, and between this
pin and the VREF pin.
(See the "Application Notes, [6]" section.)
CTL3:
I
Controls the on/off state of channel 3. A delay
can be provided in the power supply turn-on start
time by connecting a capacitor between this pin
and ground.
(See the "Application Notes, [9]" section.)
tDLY3 = 1.26 (V) × CCTL3 (µF)/1.1 (µA) (s)
This pin can also be used to control the on/off
state with an external signal. In that case, the
allowable input voltage range is from 0 V to VCC.
Note that during U.V.L.O. and timer latch
operation, this pin is connected to ground through
a 20 kΩ resistor.
CTL2:
I
Controls the on/off state of channel 2. A delay
can be provided in the power supply turn-on start
time by connecting a capacitor between this pin
and ground.
(See the "Application Notes, [9]" section.)
tDLY2 = 1.26 (V) × CCTL2 (µF)/1.1 (µA) (s)
This pin can also be used to control the on/off
state with an external signal. In that case, the
allowable input voltage range is from 0 V to VCC.
Note that during U.V.L.O. and timer latch
operation, this pin is connected to ground through
a 20 kΩ resistor.
7