MAX8805Y MAXIM [Maxim Integrated Products], MAX8805Y Datasheet - Page 11

• Manufacturer Part Number: MAX8805Y
• Description: 600mA PWM Step-Down Converters in 2mm x 2mm WLP for WCDMA PA Power
• Manufacturer: MAXIM [Maxim Integrated Products]

C3, C4
D3, D4
PIN
A1
A2
A3
A4
B1
B2
B3
B4
C1
C2
D1
D2
PAB, PAA
REFBP
PA_EN
NAME
AGND
REFIN
PGND
LDO2
LDO1
IN1B,
IN1A
EN2
EN1
IN2
HP
LX
______________________________________________________________________________________
2mm x 2mm WLP for WCDMA PA Power
Reference Noise Bypass. Bypass REFBP to AGND with a 0.22µF ceramic capacitor to reduce noise on the
LDO outputs. REFBP is internally pulled down through a 1kΩ resistor during shutdown.
Low-Noise Analog Ground
DAC-Controlled Input. The output of the PA step-down converter is regulated to 2 x V
reaches 0.465 x V
Power Ground for PA Step-Down Converter
200mA LDO Regulator 2 Output. Bypass LDO2 with a 1µF ceramic capacitor as close as possible to LDO2
and AGND. LDO2 is internally pulled down through a 1kΩ resistor when this regulator is disabled.
PA Step-Down Converter Enable Input. Connect to IN_ or logic-high for normal operation. Connect to GND
or logic-low for shutdown mode.
LDO2 Enable Input. Connect to IN2 or logic-high for normal operation. Connect to AGND or logic-low for
shutdown mode.
Inductor Connection. Connect an inductor from LX to the output of the PA step-down converter.
Supply Voltage Input for LDO1, LDO2, and Internal Reference. Connect IN2 to a battery or supply voltage
from 2.7V to 5.5V. Bypass IN2 with a 2.2µF ceramic capacitor as close as possible to IN2 and AGND.
Connect IN2 to the same source as IN1A and IN1B.
High-Power Mode Set Input. Drive HP high to invoke forced bypass mode. Bypass mode connects the
input of the PA step-down converter directly to its output through the internal bypass MOSFET. Drive HP
low to disable the forced bypass mode.
Supply Voltage Input for PA Step-Down Converter. Connect IN1_ to a battery or supply voltage from 2.7V to
5.5V. Bypass the connection of IN1_ with a 2.2µF ceramic capacitor as close as possible to IN1_, and
PGND. IN1A and IN1B are internally connected together. Connect IN1_ to the same source as IN2.
200mA LDO Regulator 1 Output. Bypass LDO1 with a 1µF ceramic capacitor as close as possible to LDO1
and AGND. LDO1 is internally pulled down through a 1kΩ resistor when this regulator is disabled.
LDO1 Enable Input. Connect to IN2 or logic-high for normal operation. Connect to AGND or logic-low for
shutdown mode.
PA Connection for Bypass Mode. Internally connected to IN1_ using the internal bypass MOSFET during
bypass mode. PA_ is connected to the internal feedback network. Bypass PA_ with a 2.2µF ceramic
capacitor as close as possible to PA_ and PGND.
600mA PWM Step-Down Converters in
IN2
, bypass mode is enabled.
FUNCTION
Pin Description
REFIN
. When V
REFIN
11