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A forum thread I'm reading for on charge pumps and the 1054 IC use.

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Linear voltage regulators are pretty easy to throw into a project if something in it needs a specific voltage that’s lower than the supply. If it needs a higher voltage, it’s almost just as easy to grab a boost converter of some sort to satisfy the power requirements. But if you’re on a mission to save some money for a large production run, or you just like the challenge of building something as simply as possible, there are ways of getting voltages greater than the supply voltage without using anything as non-minimalistic as a boost converter. [Josh] shows us exactly …read more http://pje.fyi/NmKZ5s

Additional features: -Two holes for standoffs -On-board charge pump provides the opamp with all the headroom you (should) ever need and offers additional +18V and -9V outputs for powering whatever crazy multi-FX you’re building -RPD1 & 2 are provided for applications where bypass switching is required -Buffer circuit allegedly calls upon mystical unicorns to infuse their spirit with your toanz

Just finished building and testing a charge pump that is gonig to be used in a very special circuit. it’s capable of taking +9vDC and converting it to +/- 15vDC. as you can see mine is not 100% accurate, but -15.90 and +16.16 is good enough for me and will probably not even be noticable in the final circuit. I’ve included the diagram I used so you can make one yourself. The hardest part is squeezing all those many capacitors in there. just make sure you have all the diodes and caps round the right way. The LT1054 can be a little pricey. 

ADF4113HV can be supplied now, a thousand sheets of ordering amount are offered as 2.46 dollars / slice.

Isolate while being new, step-down type, low-voltage, heavy current, ultra the intersection of Low Dropout and converter, DC/DC of charge pump, have the electric capacity of pump at the structure, its leading particulars is as follows, the output current is big, reachable 800mA; The output is tall in voltage accuracy (see Table 1 and Table 2) ; Exceed Low Dropout, is especially suitable for the walkie products; There is output voltage to be adjustable continuously and fixing two kinds of types of output voltage; Output the short circuit protection and overvoltage protection of input voltage; The module is made into the three terminal device, only need to connect input capacitor and output capacitor, it is very convenient to use; There is no inductor; The circuit is simple, all adopt the pasting type components and parts, the module size can be done minorly; The production technology is simple. Do a brief introduction of its characteristic, basic operating principle, key technical parameter, some experiment data, application area and typical application circuit now. Basic operating principle Structured flowcharts and peripheral components of the module. Its operating principle is, the output voltage is 0V (low level) in twinkling of an eye after power up ,This voltage passes the voltage divider (R1, R2) , error amplifier, the controlling circuit of input logic. The logic controlling circuit exports the low level, make the gas switching tube turned on. Then the input voltage VIN is charged to the output capacitor COUT through the gas switching tube, and supply power to load, the output voltage VOUT rises. When the voltage on COUT rises to the voltage that inside presumes, this voltage passes R1, R2 voltage divider, input the feedback voltage signal into the error amplifier, the amplifier output high level of error, the logic controlling circuit receives this high level control, export the high level, the gas switching tube ends. The output capacitor COUT discharges to load, VOUT drops, when the voltage that on COUT is slightly lower than the voltage that is presumed, through the feedback of the voltage divider, make the gas switching tube turned on, COUT also charges and improves the voltage, the output voltage like this can keep certain precision of voltage regulation. When increasing in load current, the output impulse frequency of the logic controlling circuit increases in order to guarantee the stability of output voltage; When decreasing in load current, output impulse frequency to reduce. It is the pulse frequency modulation (PFM) that this kind reaches the voltage regulation way through frequency variation Mode. Output shorting out in the protective circuit and overvoltage protective circuit of input voltage within the module. While outputting shorting out or overvoltage of input voltage, the gas switching tube ends, the output voltage is 0V, and latch. In addition, when the circuit is in the protection state, LED is on (can use and give instruction) . If R1 adopts the potentiometer, then VOUT exports adjustably. Key technical parameter The input voltage VIN is 3- 5.5V, propose the input voltage VIN =VOUT+1.0V; There are four kinds of fixed output voltage: 2.5V, 3.0V, 3.3V, 3.6V (can also produce user's required other voltage) ; The adjustable output voltage is 2.4- 4.5V; In VIN =Under VOUT +1.0V condition, output current reachable 800mA; The output is tall in voltage accuracy, the representative value of the original precision is ± 1.5%, the representative value of the voltage accuracy of the output is 2.5% when full load is outputted; Exceed Low Dropout, output current, at the 500mA, model it pigeonholes difference to be 100mA; The representative value of the quiescent current is 1.2mA; Conversion efficiency relates to magnitude of differential pressure, the conversion efficiency at the time of differential pressure 1V is about 75%; Output ripple voltage, differential pressure, output current, COUT capacity and equivalent series resistance (ESR) Magnitude is relevant. Adopt low ESR, high-capacity COUT, when IOUT is 500mA, its representative value is 15mA; VIN is greater than VOUT + (2.5- 3.5V) When, the overvoltage of input voltage, the gas switching tube is shut off, VOUT =0V, and latch (VIN needs to restart the power after reducing) ; While exporting and shorting out, VOUT =0V, and latch; The maximum power consumption PD of the gas switching tube is 1.6W. Experiment data While output current IOUT changes, examine it and press difference while seeing change and certain output current of the output voltage VOUT. Circuit of experiment. The experiment one: Relation between IOUT and VOUT Experiment condition: VIN=VOUT+1. 0V; CIN =10μ F/16V (MLCC) +220μ F/10V (Al) ; COUT =10μ F/16V (MLCC) +2* 1000μ F/10V (Al) ,1000μ F/10V electric capacity is a low ESR capacitor; Ta =25 ℃. Fixed module (4 #s and 6 #s) that exports The experimental result is shown in Table 1, adjustable output module (5 #s and 3 #s) Only make IOUT =500mA, the magnitude of voltage of actual output is listed in Table 2 in 2.5V, 3.0V, 3.3V, 3.6V, several pieces of voltage of 4.0V. Can be found out from Table 1 and Table 2, module of this experiment has better load regulation, there is the voltage accuracy of higher output. The experiment two: Low Dropout is tested The experiment method of Low Dropout is, in VIN =Under the starting condition of VOUT +1.0V, adjust RL, enable IOUT =500mA, writes down the actual value of VOUT at this moment. Then reduce VIN value gradually, has been reducing till VOUT actual value has reduced 0.1V all the time. The intersection of VIN and person who reduce at this moment reduce with the intersection of VOUT and actual value - for pigeonhole difference difference of 0.1V. Experiment condition and experiment are the same. Test the specified experiment module No. 6 with output voltage of 3.0V. VIN =4.0V, in IOUT =500mA hour, VOUT actual value is 2.98V. VIN began to reduce from 4.0V, when VIN dropped to 2.97V, VOUT actual value dropped to 2.88V from 2.98V, lowered 0.1V. It is 2.97V-2.88V=0.09V to calculate and press difference at this moment. Namely in the output current of 500mA, when VIN drops to 2.97V, the output voltage has 2.88V. This experimental result proves the differential pressure of module No. 6 is extremely low. Application area Because this DC/DC module exports the voltage range widely, and export continuously adjustably, the output current is great, differential pressure is small, and there is the voltage accuracy of better output, so the application area is relatively wide. It can make up the stabilized voltage supply of the low-voltage or be used as the accessory power supply (if the main power source is 5V/1A alone, the accessory power supply is 3V or 3.3V, 300- 400mA) ; Can make up the adapter (plug type power) which exports voltage regulation ; The adjustable power that outputs is especially suitable for the maintenance, development of circuit or electron of the experiment, fan of the small-scale electronic product of low-voltage to make; The fixed voltage regulation adapter that exports is suitable for the battery-opwered walkie electronic product and make external power source; Can also be used as the power in walkie instrument, instrument, consumption electronic product directly. Employ and give an example Use as the accessory power supply The main power source in Fig. 3 is supplied power by 7805 stabilizators, the accessory power supply is supplied power by the module SS-1 of experiment (export 3.3V/400mA) . In order to enable VIN≈ VOUT +1.0V, a diode 1N4001 of tandem connection in the incoming circuit of SS-1 module, enables VIN =4.3V. When SS-1 and main power source are very close, the input capacitor CIN of SS-1 can be saved, if C2 and SS-1 input end is farther, need to connect aluminium electrolytic capacitor of one 22- 47μ F/10V. The output capacitor is by 1000μ F/10V low ESR aluminium electrolytic capacitor and 4.7- 10μ F/16V MLCC (multi-layer ceramic capacitor) Connect in parallel, its purpose is reduced and outputted ripple voltage. Export the continuously adjustable power Fig. 4 is that a kind of output is adjustable (2.4- 4.5V) continuously ,Stabilized voltage supply of output 800mA. CIN desirable 47- 220μ F aluminium electrolytic capacitor, COUT desirable 10μ F/16V (MLCC) And 2* 1000μ F //10V low ESR aluminium electrolytic capacitor connected in parallel, outputs ripple voltage minorly. Have adopted a short-hilted broadsword and thrown the switch S1 and several kenotrons 1N4001 three times here, its purpose is to reduce the power consumption, reduce and output ripple voltage and guarantee to export 800mA electric current. The power consumption magnitude of the gas switching tube relates to VIN. In Fig. 5, input voltage VIN, output voltage VOUT, output current IOUT, then the gas switching tube is while turning on, line pressure its lower VIN-VOUT to, tube its dawdle PD for (VIN-VOUT) *IOUT. When VIN-VOUT is big, its PD may exceed the dissipated power of the gas switching tube maximum and damage the gas switching tube, even not damage the gas switching tube, will make conversion efficiency reduce, ripple voltage increases. So propose VIN =VOUT +1.0V is comparatively suitable. The relation between position and input and output voltage of S1 switch is shown in Table 3. Use the battery-opwered power Fig. 6 is that the nickel-cadmium or nickel-hydrogen of three section is battery-driven, the stabilized voltage supply of output 3.0V/300mA. This power of maximum characteristics are, when the voltage of the battery drop to 3.0V from the nominal voltage 3.6V, output voltage still reachable about 2.90V. When this has not merely fully utilized energy (battery of the battery to 3.0V in order to stop the discharge voltage) ,And lengthened the battery for time while charging twice. In addition, because the differential pressure of VIN-VOUT is small, its conversion efficiency is greater than 84%. When differential pressure is very small, the duty ratio of the gas switching tube is improved, it ripple voltage reduces correspondingly; As the minima of differential pressure, the duty ratio of the gas switching tube is 1, the gas switching tube is not reopened, it is 0mV that it outputs ripple voltage, this is one of the characteristics of this circuit too. From: http://www.epc.com.cn/magzine/20060105/4510.asp