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MAXIM New Products - DS1267B & MAX16936
2013-03-11
DS1267B
Dual Digital Potentiometer
±5V, 2-Channel Digital Potentiometer Recommended Replacement Device for DS1267
Description
The DS1267B has two 256-position potentiometers, with wiper positions each set by stored 8-bit values. The DS1267B communicates through a 3-wire serial port interface that drives an internal control logic unit. Multiple DS1267Bs can be linked or daisy-chained for control by a single processor.
The DS1267B dual digital potentiometer replaces the DS1267, which has been discontinued. The device is designed for flexibility, operating from a single +5V or dual ±5V supply. Maximum standby current is only 2µA.
Digital potentiometers improve upon mechanical devices with processor control and programmability, greater reliability and accuracy, and packaging options that facilitate automatic assembly. They are used for signal control in modems and phones, battery charging and control circuitry, tuning and calibration, offset trimming of operational amplifiers, gain control, and power-supply regulation.
Key Features
- Two 256-Step (or 8-Bit) Digital Potentiometers
- Stacking Configures Device as One 512-Step (or 9-Bit) Digital Potentiometer
- Wipers Digitally Set and Read Through Serial Port
- 3-Wire Serial Control Interface
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Operating Ranges
- Single +5V or ±5V Supplies
- -40°C to +85°C
MAX16936
36V, 220kHz to 2.2MHz Step-Down Converter with 28µA Quiescent Current
2.5A Automotive Buck with FPWM Capability at Light Loads for EMI Management
Description
The MAX16936 is a 2.5A current-mode step-down converter with integrated high-side and low-side MOSFETs designed to operate with an external Schottky diode for better efficiency. The low-side MOSFET enables fixed-frequency forced-PWM (FPWM) operation under light-load applications. The device operates with input voltages from 3.5V to 36V, while using only 28µA quiescent current at no load. The switching frequency is resistor programmable from 220kHz to 2.2MHz and can be synchronized to an external clock. The MAX16936’s output voltage is available as 5V/3.3V fixed or adjustable from 1V to 10V. The wide input voltage range along with its ability to operate at 98% duty cycle during undervoltage transients make the MAX16936 ideal for automotive and industrial applications.
Under light-load applications, the FSYNC logic input allows the MAX16936 to either operate in skip mode for reduced current consumption or fixed-frequency FWM mode to eliminate frequency variation to minimize EMI. Fixed-frequency FPWM mode is extremely useful for power supplies designed for RF transceivers where tight emission control is necessary. Protection features include cycle-by-cycle current limit and thermal shutdown with automatic recovery. Additional features include a power-good monitor to ease power-supply sequencing and a 180° out-of-phase clock output relative to the internal oscillator at SYNCOUT to create cascaded power supplies with multiple MAX16936s.
The MAX16936 operates over the -40°C to +125°C automotive temperature range and is available in 16-pin TSSOP-EP and 5mm × 5mm, 16-pin TQFN-EP packages.
Under light-load applications, the FSYNC logic input allows the MAX16936 to either operate in skip mode for reduced current consumption or fixed-frequency FWM mode to eliminate frequency variation to minimize EMI. Fixed-frequency FPWM mode is extremely useful for power supplies designed for RF transceivers where tight emission control is necessary. Protection features include cycle-by-cycle current limit and thermal shutdown with automatic recovery. Additional features include a power-good monitor to ease power-supply sequencing and a 180° out-of-phase clock output relative to the internal oscillator at SYNCOUT to create cascaded power supplies with multiple MAX16936s.
The MAX16936 operates over the -40°C to +125°C automotive temperature range and is available in 16-pin TSSOP-EP and 5mm × 5mm, 16-pin TQFN-EP packages.
Key Features
- Wide 3.5V to 36V Input Voltage Range
- 42V Load Dump Protection
- Enhanced Current-Mode Control Architecture
- Fixed Output Voltage with ±2% Accuracy (5V/3.3V) or Externally Resistor Adjustable (1V to 10V)
-
220kHz to 2.2MHz Switching Frequency with Three Operation Modes
- 28µA Ultra-Low Quiescent Current Skip Mode
- Forced Fixed-Frequency Operation
- External Frequency Synchronization
- Spread-Spectrum Frequency Modulation
- Automatic LX Slew Rate Adjustment for Optimum Efficiency Across Operating Frequency Range
- 180° Out-of-Phase Clock Output at SYNCOUT
- Low-BOM-Count Current-Mode Control Architecture
- Power-Good Output
- Enable Input Compatible from 3.3V Logic Level to 42V
- Thermal Shutdown Protection
- -40°C to +125°C Automotive Temperature Range
- AEC-Q100 Qualified
