Datasheet

DEF_1
FB1
MODE/DATA
VIN
EN1
SW2
ADJ2
GND
EN2
Pow
e
r
PAD
SW1
1
2
3
4
5
10
9
8
7
6
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TPS62420, TPS62421
www.ti.com SLVS676C –JUNE 2006–REVISED JUNE 2010
DEVICE INFORMATION
PIN ASSIGNMENTS
TERMINAL FUNCTIONS
TERMINAL
I/O DESCRIPTION
NO.
NAME
(QFN)
ADJ2 1 I Input to adjust output voltage of converter 2. In adjustable version (TPS62420) connect a external
resistor divider between VOUT2, this pin and GND to set output voltage between 0.6V and VIN. If
EasyScale™ Interface is used for converter 2, this pin must be directly connected to the output.
MODE/DATA 2 I This Pin has 2 functions:
1. Operation Mode selection: With low level, Power Save Mode is enabled where the device
operates in PFM mode at light loads and enters automatically PWM mode at heavy loads. Pulling
this PIN to high forces the device to operate in PWM mode over the whole load range.
2. EasyScale™ Interface function: One wire serial interface to change the output voltage of both
converters. The pin has an open drain output to provide an acknowledge condition if requested.
The current into the open drain output stage may not exceed 500mA. The interface is active if
either EN1 or EN2 is high.
VIN 3 I Supply voltage, connect to VBAT, 2.5V to 6V
FB1 4 I Direct feedback voltage sense input of converter 1, connect directly to Vout 1. An internal feed forward
capacitor is connected between this pin and the error amplifier. In case of fixed output voltage versions
or when the Interface is used, this pin is connected to an internal resistor divider network.
DEF_1 5 I/O This pin defines the output voltage of converter 1. The pin acts in TPS62420 as an analog input for
output voltage setting via external resistors. In fixed default output voltage versions this pin is a digital
input to select between two fixed default output voltages, see table ordering information.
In TPS62420 an external resistor network needs to be connected to this pin to adjust the default output
voltage.
SW1 6 Switch Pin of Converter1. Connected to Inductor
EN1 7 I Enable Input for Converter1, active high
GND 8 I GND for both converters, this pin should be connected with the PowerPAD
EN2 9 I/O Enable Input for Converter 2, active high
SW2 10 Switch Pin of Converter 2. Connected to Inductor.
PowerPAD™ Connect to GND
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Product Folder Link(s): TPS62420 TPS62421