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DESIGN & PRODUCTS HG V LA E ver POWR607 is one example of anLattice’s Power Manager IIOGTOHI 2500 Std.Models integrated power management Surface Mount and Thru-Hole solution that minimizes power issues by accurately monitoring all DC-DC Converters and optimizing the sequence ofvoltages, minimizing reset delays, 2V to 10,000 VDC Outputs power supplies on and off. Low Profile / Isolated Figure 2 shows a Power Man- Fig. 3: Lowering cost and complexity. Up to 10,000 Volts Standard ager II device monitoring and control- estate can be restrictive, especially in Regulated Models Available ling several key SSD power supplies smaller portable applications, but may and auxiliary power management be minimized by using super capaci- functions that are critical to reliable SSD tors. These super capacitors require operation. The power management de- careful management, because the num- vice implements the hot swap controller ber of times they can be charged is very that limits the inrush current into the limited and their lifespan can be cut in hold-up capacitor. It also integrates the half at higher temperatures. hold-up capacitor controller that man- Tantalum capacitors provide less ages the charge/discharge path of the capacitance density than super ca- hold-up capacitor, providing momentary pacitors, but are more reliable, less backup power. It has multiple GPIOs expensive and are available in higher that can be programmed to sequence voltages. We can see by C=q/V that power supplies while monitoring the voltage is inversely proportional to the voltage on the outputs to ensure that capacitance. By using higher voltage wwwpicoelectronics.com down power and device sequencing. capacitors in the bank roughly in half.boost converter to double the chargevoltage, we can reduce the amount of-to the next sequencing instruction. Thisprovides predictable startup and shutiltantalum capacitors and then adding athey are in regulation before proceedingetdemiglatacluf’OCI.PeeS The power management device can This is shown in the top half of figure 3. High capacitor, then isolate it from the sys- ment a high efficiency buck converter-Designers may also choose to implebe programmed to charge the hold-up Power power during a shutdown sequence. optimum conversion voltages of theto decrease the high voltage requiredby the hold-up capacitor down to thetem until it requires “topping off” or isrequired to provide momentary backup Up to 350 VDC Outputs Managing the hold-up reduce cost and increase efficiency.secondary DC-DC converters. This will (Units up to 150 Watts) capacitor Of course, adding converters and Regulated / Wide Input Range Designs that require momentary backup their support circuitry increases com- Isolated Outputs power using a hold-up capacitor need plexity and expense. A simpler, more additional consideration. Designers cost effective solution is shown in the must calculate the amount of ca- bottom half of figure 3. A charge pump pacitance needed to hold-up the input can be used instead of a boost convert- voltage to the DC-DC converters so the er to increase the voltage applied to the system has enough time to properly hold-up capacitor. Implementing a two- shutdown and complete the transfer of or three-stage charge pump can double data to non-volatile memory. Depending or triple the voltage stored on the hold- on each system’s load and shutdown up capacitor. In the case of 12V SSDs, response time, this can require up to a tripling of the input voltage enables the PICO Faxlectr-73ic-8Inc. tors typically are utilized. The size of the cost - electrolytic capacitors. -Careful attention to power manageuse of lower efficiency - but even lower-farad of capacitance. To achieve thislevel of capacitance, banks of capaci522,s8no419E 143 Sparks Ave. Pelham, N.Y. 10803 E Mail: info@picoelectronics.com banks and the corresponding board real ment is critical for solid state drive reli- ability. Lattice Semiconductor’s Power Delivery Stock to One Week for sample quantities Manager II simplifies SSD power man- agement by integrating precise power Pico Representatives supply sequencing, accurate voltage Germany ELBV/Electronische Bauelemente Vertrieb monitoring and fast supervisory resets E-mail: info@elbv.de into a programmable solution. It elimi- Phone: 0049 89 4602852 Fax: 0049 89 46205442 nates the need for separate discrete England hot swap or holdup capacitor control- Ginsbury Electronics Ltd. lers. It can also replace the expensive E-mail: rbennett@ginsbury.co.uk Phone: 0044 1634 298900 boost converters used for holdup ca- Fax: 0044 1634 290904 pacitor charging with a simple charge Fig. 2: Managing backup power. pump. 54 Electronic Engineering Times Europe November 2012 www.electronics-eetimes.com


EETE NOVEMBER 2012
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