MAX750A

Features:

Up to 750mA Load Currents
160kHz High-Frequency, Current-Mode PWM
85% to 96% Efficiencies
33µH or 100µH Pre-Selected Inductor Value, No Component Design Required
1.7mA Quiescent Supply Current
6µA Shutdown Supply Current
Adjustable Output Voltage
Overcurrent, Soft-Start, and Undervoltage Lockout Protection
Cycle-by-Cycle Current Limiting
8-Pin DIP/SO Packages (MAX750A)


Application

Cellular Phones & Radios
Portable Communications Equipment
Portable Instruments
Computer Peripherals


Pinout




Specifications

Pin Voltages
V+ (MAX750A)...............................................................+12V, -0.3V
V+ (MAX758A)...............................................................+18V, -0.3V
LX (MAX750A) ..........................................(V+ - 12V) to (V+ + 0.3V)
LX (MAX758A) ..........................................(V+ - 21V) to (V+ + 0.3V)
SS, CC, SHDN...................................................-0.3V to (V+ + 0.3V)
Peak Switch Current (ILX)...........................................................2A
Reference Current (IREF) ......................................................2.5mA
Power Dissipation (TA = +70°C)
   8-Pin Plastic DIP (derate 9.09mW/°C above +70°C) .....727mW
   8-Pin SO (derate 5.88mW/°C above +70°C)..................471mW
   16-Pin Wide SO (derate 9.52mW/°C above +70°C) ......762mW
    8-Pin CERDIP (derate 8.00mW/°C above +70°C)..........640mW
Operating Temperature Ranges:
MAX75_AC_ _ .........................................................0°C to +70°C
MAX75_AE_ _ ......................................................-40°C to +85°C
MAX75_AMJA......................................................-55°C to +125°C
Junction Temperatures:
MAX75_AC_ _/AE_ _..........................................................+150°C
MAX75_AMJA .....................................................................+175°C
Storage Temperature Range .............................-65°C to +160°C
Lead Temperature (soldering, 10sec) .............................+300°C


Description

The MAX750A/MAX758A are adjustable-output, CMOS,step-down, DC-DC switching regulators.  The MAX758A accepts inputs from 4V to 16V and delivers 750mA, while the MAX750A accepts inputs from 4V to 11V and delivers 450mA.  Ty-pical efficiencies are 85% to 90%.  Typical quiescent current is 1.7mA, or only 6µA in shutdown mode.  The output does not exhibit any ripple at subharmonics of the switching frequency over its specified range.
Pulse-widthmodulation (PWM) current-mode control of MAX750A provides precise output regulation and excellent transient res-ponses.  Output voltage accuracy is guaranteed to be ±4.5% plus feedback-resistor tolerance over line, load, and temperature variations.  Fixed-frequency switching and absence of subharmonic ripple allows easy filtering of output ripple and noise, as well as the use of small external components.  These regulators MAX750A require only a single inductor value to work in most applications, so no inductor design is necessary.