Datasheet

Evaluation Board User Guide UG-117
Rev. A | Page 3 of 8
EVALUATION BOARD HARDWARE
EVALUATION BOARD CONFIGURATIONS
The ADP160/ADP161/ADP162/ADP163 evaluation board
comes supplied with different components, depending on the
version that is ordered. Components common to all versions are
C1, C2, and J1. Resistors R1 and R2 and Jumper J2 are used for
the adjustable output ADP161. Figure 3 and Figure 4 show the
schematics of these evaluation board configurations. Table 1
describes the components.
The adjustable ADP161 has an output voltage range of 1.0 V to
4.0 V. The output voltage is set by the ratio of two external resistors,
as shown in Figure 3. The device servos the output to maintain
the voltage at the ADJ pin at 1.0 V referenced to ground. The
current in R1 is then equal to 1.0 V/R2, and the current in R1
is the current in R2 plus the ADJ pin bias current. The ADJ pin
bias current, 10 nA at 25°C, flows through R1 into the ADJ pin.
The output voltage can be calculated using the following
equation:
V
OUT
= 1.0 V(1 + R1/R2) + (ADJ
I-BIAS
)(R1)
The value of R1 should be less than 200 k to minimize errors
in the output voltage caused by the ADJ pin bias current. For
example, when R1 and R2 each equal 200 k, the output voltage
is 2.0 V. The output voltage error introduced by the ADJ pin
bias current is 1 mV or 0.05%.
To minimize quiescent current in the ADP161 and ADP163, use
high values of resistance for R1 and R2. Using a value of 1 MΩ for
R2 keeps the total, no load quiescent current below 2 µA. Note,
however, that high values of resistance introduce a small output
voltage error. For example, assuming R1 and R2 are 1 MΩ, the
output voltage is 2 V. Taking into account the nominal ADJ pin
bias current of 10 nA, the output voltage error is 0.25%.
Note that in shutdown, the output is turned off and the divider
current is zero.
5
4
1
2
3
VIN
GND
EN
VOUT
NC/
ADJ
J2
J1
C2
C1
R1
R2
VOUT
U1
08935-003
Figure 3. Evaluation Board Schematic, TSOT
C2
J1
C1
VOUT
U1
08935-004
VOUTVIN
GNDEN
VIN
Figure 4. Evaluation Board Schematic, WLCSP
Table 1. Evaluation Board Hardware Components
Component Description
U1
1
ADP160/ADP161/ADP162/ADP163low dropout
linear regulator
C1
2
Input bypass capacitor, 1 F, 0603 size
C2
2
Output capacitor, 1 µF, 0603 size
J1 Jumper (connects EN to VIN for automatic startup)
J2
Jumper (connects VOUT to the resistor divider
for the adjustable ADP161)
R1, R2
Resistor divider to set ADP161/ADP163 output
voltage
1
The evaluation board with the WLCSP package is the ADP16xCB-xxx-EVALZ.
The evaluation board with the TSOT package is the. ADP16xUJ-xxx-EVALZ.
2
The ADP16x evaluation boards require only one input bypass capacitor and
one output capacitor for stable operation.