Rainbow Electronics MAX1510 - Manual (Page 12)

MAX1510
Low-Voltage DDR Linear Regulator
12 ______________________________________________________________________________________
Noise, PSRR, and Transient Response
The MAX1510 operates with low-dropout voltage and
low quiescent current in notebook computers while
maintaining good noise, transient response, and AC
rejection specifications. Improved supply-noise rejec-
tion and transient response can be achieved by
increasing the values of the input and output capaci-
tors. Use passive filtering techniques when operating
from noisy sources.
The MAX1510 load-transient response graphs (see the
Typical Operating Characteristics) show two compo-
nents of the output response: a DC shift from the output
impedance due to the load-current change and the
transient response. A typical transient response for a
step change in the load current from -1.5A to +1.5A is
10mV. Increasing the output capacitor’s value and
decreasing the ESR attenuate the overshoot.
PC Board Layout Guidelines
The MAX1510 requires proper layout to achieve the
intended output power level and low noise. Proper lay-
out involves the use of a ground plane, appropriate
component placement, and correct routing of traces
using appropriate trace widths. Refer to the MAX1510
evaluation kit for a layout example.
1) Minimize high-current ground loops. Connect the
ground of the device, the input capacitor, and the
output capacitor together at one point.
2) To optimize performance, a ground plane is essen-
tial. Use all available copper layers in applications
where the device is located on a multilayer board.
3) Connect the input filter capacitor less than 10mm
from IN. The connecting copper trace carries large
currents and must be at least 2mm wide, preferably
5mm wide.
4) Connect the backside pad to a large ground plane.
Use as much copper as necessary to decrease the
thermal resistance of the device. In general, more
copper provides better heatsinking capabilities.
Chip Information
TRANSISTOR COUNT: 3496
PROCESS: BiCMOS