19-4059; Rev 1; 9/08
1.2A PWM Step-Down Converter in
2mm x 2mm WLP/UCSP for PA Power
The MAX8836Z high-frequency step-down converter is
optimized to provide a fixed output voltage with ultra-
low dropout. The device integrates a high-efficiency
PWM step-down converter for medium- and low-power
transmission, and a 60mΩ typical bypass FET for ultra
low-dropout operation. A 200mA low-noise, high-PSRR
low-dropout regulator (LDO) is also integrated.
Fast-switching allows the use of small ceramic input and
output capacitors while maintaining low ripple voltage.
The feedback network is integrated, further reducing
external component count and total solution size. At high
duty cycle, the MAX8836Z automatically switches to the
bypass mode, connecting the input to the output
through a low-impedance (60mΩ typ) MOSFET. The
LDO in the MAX8836Z is designed for low-noise opera-
tion (35µVRMS typ). Both the PWM step-down and LDO
are individually enabled through separate logic-control
The MAX8836Z is available in 16-bump, 2mm x 2mm
WLP and UCSP™ packages (0.7mm max height).
WCDMA/NCDMA Cellular Handsets
PIN-PACKAGE TEMP RANGE
-40°C to +85°C
MAX8836ZEREEE+T 16 UCSP
-40°C to +85°C
+Denotes a lead-free/RoHS-compliant package.
T = Tape and reel.
o PA Step-Down Converter
Selectable Output Voltage (3.1V or 3.4V)
25µs Settling Time for 3.1V to 3.4 VOUT Change
60mΩ PFET at 100% Duty-Cycle for Low
Low Output Voltage Ripple
1.2A Output Drive Capability
±2% Output Voltage Accuracy
Tiny External Components
o Low-Noise LDO
Low 35µVRMS (typ) Output Noise
High 65dB (typ) PSRR
Guaranteed 200mA Output Current Drive
o Low 0.1µA Shutdown Current
o 2.7V to 5.5V Supply Voltage Range
o Thermal Shutdown
o Tiny 2mm x 2mm x 0.7mm WLP and UCSP
Packages (4 x 4 Grid)
Typical Operating Circuit
3.1V OR 3.4V
Pin Configuration appears at end of data sheet.
UCSP is a trademark of Maxim Integrated Products, Inc.
________________________________________________________________ Maxim Integrated Products 1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim's website at www.maxim-ic.com.