Linear Technology Chronicle August 20001A Showcase of Linear Technologys Focus ProductsProduct of the Month, LTC and LT are registered trademarks of Linear Technology Corporation. No Latency Delta-Sigma, Burst Mode and OPTI-LOOP are trademarks of Linear Technology Corporation. I2C is a trademark of Philips Electronics N.V.Linear Technology ChronicleAugust 2000Vol. 9 No. 8Inside This Issue:Smallest RF Power Controller for Single and Dual Band GSM/PCS Phones Minimizes Test TimeLTC1757A. 2 Single Cell Li-Ion to 3.3V Converter is Tiny and Draws Very Low PowerLT1615 . 3 Parallel 16-Bit Rail-to-Rail Output DAC Gives 16-Bit Monotonicity On a Single 3V SupplyLTC1657L . 3 Smallest and Most Efficient High Current Synchronous Regulators for Processors, ASICs and FPGAs . 4Figure 1. LTC2410 Directly Digitizes Differential Bridge Output24-Bit, No Latency Delta-SigmaTM ADC with Differ- ential Inputs and Differential ReferenceLTC2410Continued on page 2The LTC2410 is the most accurate, simplest and smallest 24-bit analog-to-digi- tal converter with differential inputs on the market today. This device operates on sup- plies from 2.7V to 5.5V and can accept any differential reference voltage from 0.1V to VCC, providing flexibility in ratiometric and remote sensing applications. It consumes just 200A during conversion and 20A during shutdown. The LTC2410s 16-pin SSOP package is the same size as an SO-8 and is smaller than any other high resolution ADC with differential inputs. The LTC2410s accuracy, features and small size mean ease-of-use and ease-of-design in applications such as weigh scales, tempera- ture measurements, gas analyzers, strain gauge transducers and other applications that demand precise measurement.The LTC2410 automatically performs transparent offset and full-scale calibration on every conversion to provide 5ppm total unadjusted error, 0.5V offset error and 2.5ppm full-scale error with unmeasurable drifts (only 0.001ppm/C). Its high accu- racy DNL guarantees true 24-bit output with no missing codes and its integral non- linearity (INL) is only 2ppm (2.5V refer- ence). The output noise of the LTC2410 is only 800nV with a wide 5V input range, eliminating the need for PGAs. The LTC2410 has a proprietary no latency ar- chitecture that allows single cycle settling for multiplexed applications. Single cycle settling and transparent calibration simplify system design by reducing software over- head. The performance of the LTC2410 provides the highest level of accuracy forthe most demanding “bridge to bits” appli- cations (see Figure 1). The LTC2410 includes a highly accu- rate on-chip oscillator, eliminating the need for external frequency setting components such as crystals or oscillators. Pin selectable 50Hz/60Hz notch frequency of the 4th order sync filter allows 120dB rejection of line frequencies 2% with the on-chip oscillator. The common mode rejection ratio (CMRR) of its differential input at 60Hz is an impres- sive 140dB. When clocked externally, the LTC2410 allows output word rates up to 15Hz. Faster rates are possible at reduced resolution. This device eliminates configura- tion and calibration registers, external com- ponents and special filtering that other high resolution ADCs require. The LTC2410 is available in both commercial and industrial temperature ranges in the space saving 16-pin SSOP package.LTC2410IN+REF+VCCREFVCCGNDFOIN1FSDO3-WIRE SPI INTERFACESCK2410 TA02CS12321, 7, 8 9, 10, 15, 16145641311BRIDGE IMPEDANCE 100 TO10k0.05%, 10ppm/C, SOT-23 Series Reference Features 0.1V Dropout and 35A Supply Current LT1790Despite its tiny SOT-23 package, the LT1790 provides very high precision and low noise (Table 1). Small size and precision plus the 35A supply current and low drop- out voltage make the LT1790 ideal for use in battery pack and battery-powered portable products. The LT1790 generates noise of only 12VP-P (0.1Hz to10Hz), the lowest of any SOT-23 low dropout voltage reference. Low noise benefits noise-sensitive products such as precision handheld instruments and base stations for wireless communications.2Linear Technology Chronicle August 2000Contact your local Linear Technology sales office for a data sheet and evaluation samples. For more information, visit our web site at www.linear-tech.com.LT1790 from page 1With the wide 40C to 125C operat- ing temperature range and low thermally induced hysteresis, the LT1790 is the first SOT-23 reference suitable for use in harsh environments such as automotive and indus- trial systems. The lower thermal resistance of the 6-pin package provides a greater ther-mal margin than 3-lead SOT-23 packages in high ambient temperature conditions. The long-term drif