LP2980-N_16 Datasheet, PDF (20/30 Pages) Texas Instruments – Micropower 50-mA Ultra Low-Dropout Regulator in SOT-23 Package

LP2980-N
SNOS733O – APRIL 2000 – REVISED JUNE 2015
www.ti.com
9 Power Supply Recommendations
The LP2980-N is designed to operate from an input voltage supply range between 2.1 V and 16 V. The input
voltage range provides adequate headroom for the device to have a regulated output. This input supply must be
well regulated. If the input supply is noisy, additional input capacitors with low ESR can help improve the output
noise performance.
10 Layout
10.1 Layout Guidelines
For best overall performance, place all circuit components on the same side of the circuit board and as near as
practical to the respective LDO pin connections. Place ground return connections to the input and output
capacitors, and to the LDO ground pin as close to each other as possible, connected by a wide, component-side,
copper surface. The use of vias and long traces to create LDO circuit connections is strongly discouraged and
negatively affects system performance. This grounding and layout scheme minimizes inductive parasitics, and
thereby reduces load-current transients, minimizes noise, and increases circuit stability. A ground reference
plane is also recommended and is either embedded in the PCB itself or located on the bottom side of the PCB
opposite the components. This reference plane serves to assure accuracy of the output voltage, shield noise,
and behaves similar to a thermal plane to spread (or sink) heat from the LDO device. In most applications, this
ground plane is necessary to meet thermal requirements.
10.2 Layout Example
VIN
Input
IN
Capacitor
OUT
VOUT
Output
Capacitor
GND
Ground
ON/OFF
ON/OFF
NC
Figure 41. LP2980-N Layout Example
20
Submit Documentation Feedback
Product Folder Links: LP2980-N
Copyright © 2000–2015, Texas Instruments Incorporated