Linear Battery Charger with Multi-Chemistry Operation

Linear Technology Corp. recently introduced the LTC4079, which is a 60-V, constant-current/constant-voltage, 250-mA multi-chemistry battery charger. According to Linear, its “low quiescent current linear topology offers a simple inductorless design and accepts a wide 2.7 V to 60 V input voltage range.”LinearLTC4079

 

The LTC4079’s features, characteristics, and capabilities include:

  • A resistor-programmable 1.2- to 60-V battery charge voltage range with ±0.5% charge voltage accuracy
  • Adjustable charge current from 10 to 250 mA with an external resistor
  • A low-profile (0.75 mm) 10-pin 3 mm x 3 mm DFN package with backside metal pad for excellent thermal performance.
  • Guaranteed foperation from –40°C to 125°C in both E-and I-grades.
  • One thousand-piece pricing starts at $2.35 each for the E-grade.

Source: Linear Technology

LTC2946 Wide-Range I2C Power, Charge, and Energy Monitor

Linear Technology Corp. recently introduced the LTC2946, which is a high- or low-side charge, power and energy monitor for DC supply rails in the 0-to-100-V range. According to Linear Technology’s release:

An integrated ±0.4% accurate, 12-bit ADC and external precision time base (crystal or clock) enables measurement accuracy better than ±0.6% for current and charge, and ±1% for power and energy. A ±5% accurate internal time base substitutes in the absence of an external one. All digital readings, including minimums and maximums of voltage, current and power, are stored in registers accessible by an I²C/SMBus interface. An alert output signals when measurements exceed configurable warning thresholds, relieving the host of burdensome polling for data. The LTC2946 provides access to all the necessary parameters to accurately assess and manage board level energy consumption. In addition its wide operating range makes it ideal for monitoring board energy consumption in blade servers, telecom, solar and industrial equipment, and advanced mezzanine cards (AMC).

Source: Linear Technology

Source: Linear Technology

The LTC2946’s features include

  • 0 to 100 V Monitoring Range; greater than 100 V with internal shunt regulator
  • 12-Bit ADC with Scan and Snapshot Modes
  • I²C/SMBus digital interface
  • Guaranteed Accuracy: ±0.4% for 12-bit voltage; ±0.6% for 12-bit current and 32-bit charge; and ±1% for 24-bit power and 32-bit energy
  • Internal ±5%, external or crystal time bases
  • Minimum and maximum value recorder
  • Bias Supply Range: 4 to 100 V, or 2.7 to 5.9 V
  • Alerts on exceeding warning thresholds
  • Split SDA eases optoisolation
  • Shutdown Mode with IQ < 40 µA
  • 16-pin MSOP and 4 mm × 3 mm DFN Packages

Source: Linear Technology

Linear LT3999 DC/DC Transformer Driver

Linear Technology recently launched the LT3999 monolithic push-pull isolated DC/DC transformer driver with two 1-A current limited power switches. It operates over an input voltage of 2.7 to 36 V and is targeted for power levels up to 15 W, making it a good option for a variety of industrial applications.

Source: Linear Technology

Source: Linear Technology

The LT3999’s features include:

  • Wide VIN range: 2.7 to 36 V
  • Dual 1-A switches
  • Programmable switching frequency: 50 kHz to 1 MHz
  • Synchronizable to an external clock up to 1 MHz
  • Duty cycle control for output voltage regulation
  • Low noise topology
  • Programmable input over- and under-voltage lockout
  • Cross-conduction prevention circuitry
  • Extended and industrial grades: –40° to 125°C operating junction temperature
  • Automotive temperature grade: –40° to 150°C operating junction temperature
  • Military temperature grade: –55° to 150°C operating junction temperature

The LT3999’s 1,000-piece price starts at $2.75 each for the E-grade.

Source: Linear Technology

 

LT8580 Boost/SEPIC/Inverting DC/DC Converter

Linear Technology Corporation recently announced the availability of the LT8580 current-mode, fixed-frequency, step-up DC/DC converter with an internal 1-A, 65-V switch. Operating from an input voltage range of 2.55 to 40 V, you’ll find the LT8580 useful for a variety of applications with input sources ranging from a single-cell Li-Ion to automotive inputs.

Source: Linear Technology

Source: Linear Technology

Key points:

  • Configurable as either a boost, SEPIC or an inverting converter
  • 3 mm × 3 mm DFN package (or MSOP-8E) and tiny externals
  • Low VCESAT switch (0.4 at 0.75 A) delivers efficiencies of up to 86%
  • User-adjustable UVLO

Pricing starts at $2.35 each for 1,000-piece quantities.

Source: Linear Technology

100-V Forward Voltage Controller

Linear Technology recently announced the LT8310, which is a resonant-reset forward converter controller that drives an external low side N-channel MOSFET from an internally regulated 10-V supply. The LT8310 features duty mode control to generate a stable, regulated, isolated output using a single power transformer. With the addition of output voltage feedback, via optocoupler (isolated) or directly wired (nonisolated), current mode regulation is activated, improving output accuracy and load response. A choice of transformer turns ratio makes high step-down or step-up ratios possible without operating at duty cycle extremes.

Source: Linear Technology

Source: Linear Technology

The switching frequency is programmable from 100 kHz to 500 kHz to optimize efficiency, performance or external component size. A synchronous output is available for controlling secondary side synchronous rectification to improve efficiency. User programmable protection features include monitors on input voltage (UVLO and OVLO) and switch current (overcurrent limit). A soft-start feature helps prevent transformer flux saturation.

The LT8310 main features include:

  • Input voltage range: 6 V to 100 V
  • Duty mode control regulates an isolated output without an opto
  • High efficiency synchronous control
  • Short-circuit (Hiccup mode) overcurrent protection
  • Programmable OVLO and UVLO with hysteresis
  • Programmable frequency (100 kHz to 500 kHz)
  • Synchronizable to an external clock
  • Positive or negative polarity output voltage feedback with a single FBX pin
  • Programmable soft-start
  • Shutdown current < 1 μA

The LT8310 is available in an FE20 TSSOP with high voltage pin spacing

Source: Elektor