ADP1148 Analog Devices, ADP1148 Datasheet
ADP1148
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ADP1148 Summary of contents
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... Telecom Power Supplies GPS Systems Cellular Telephones GENERAL DESCRIPTION The ADP1148 is part of a family of synchronous step-down switching regulator controllers featuring automatic sleep mode to maintain high efficiencies at low output currents. These devices drive external complementary power MOSFETs at switching frequencies up to 250 kHz using a constant off-time current-mode architecture ...
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... Dynamic supply current is higher due to the gate charge being delivered at the switching frequency. The allowable operating frequency may be limited by power dissipation at high input voltages. 4 The ADP1148 version is tested with external feedback resistors, setting the nominal output voltage to 3.3 V. Specifications subject to change without notice. 1 ...
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... Dynamic supply current is higher due to the gate charge being delivered at the switching frequency. The allowable operating frequency may be limited by power dissipation at high input voltages. 4 The ADP1148 version is tested with external feedback resistors setting the nominal output voltage to 3.3 V. Specifications subject to change without notice. ABSOLUTE MAXIMUM RATINGS Input Supply Voltage (Pin – ...
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... R , sets the current trip threshold. SENSE 9 V For the ADP1148 adjustable version, Pin 9 serves as the feedback pin from an external resistive divider FB used to set the output voltage. On ADP1148-3.3 and ADP1148-5 versions, this pin is not used. 10 Shutdown Taking Pin 10 of the ADP1148, ADP1148-3.3 or ADP1148-5 high holds both MOSFETs off. Must be at ground potential for normal operation ...
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... Inductor IN OUT +40 + 0.1A LOAD – LOAD –40 FIGURE 1 CIRCUIT – Figure 8. ADP1148-5 Output Voltage Change vs. Input Voltage SHUTDOWN INPUT VOLTAGE – V Figure 11. Supply Current in Shutdown 5 ...
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... ADP1148, ADP1148-3.3, ADP1148-5–Typical Performance Characteristics 1 1.0 0.8 0.6 0.4 0.2 0 –V ) – OUT Figure 12. Operating Frequency vs. (V – OUT 155 150 145 MAXIMUM THRESHOLD 140 135 130 125 120 100 TEMPERATURE – C Figure 15. Current Sense Threshold ...
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... I value less half the peak-to-peak ripple current. The ADP1148 operates effectively with values of R 200 graph for selecting R current is given in Figure 3. Solving for R ...
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... ESR requirements for the output capacitor are relaxed at the expense of efficiency. If too small an inductor is used, the induc- tor current will decrease past zero and change polarity. A result of this occurrence will be that the ADP1148 may not be in power saving mode operation and efficiency will be significantly reduced at low currents. ...
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... OUT current increases from 0 efficiency to roll-off at high output currents. Figure 6 shows how the efficiency losses in a typical ADP1148 regulator. The gate charge loss is responsible for the majority of the efficiency lost in the midcurrent region. If power saving mode operation was not employed at low currents, the gate charge loss alone would cause the efficiency to drop to unac- ceptable levels ...
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... Note: under shutdown conditions, the N-channel MOSFET 1.27 = 120 m is held OFF and pulling the N-channel MOSFET to crowbar the output. A simple N-channel FET can be used as an interface between the overvoltage detect circuitry and the ADP1148 as shown in Figure 16 will result, increas- Troubleshooting ...
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... C and signal ground. OUT 3) Are the SENSE(–) and SENSE(+) leads routed together with minimum PC trace spacing? The 1000 pF capacitor between Pins 7 and 8 should be as close as possible to the ADP1148 10nF 1k Figure 18. ADP1148 Layout Diagram (See Board Layout) REV ...
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... ADP1148, ADP1148-3.3, ADP1148 300pF 10nF Figure 19. ADP1148 Low Dropout, 3.3 V/1 A High Efficiency Regulator 560pF 10nF 6800pF 1k Figure 20 Input Voltage to –5 V/1.4 A Regulator IRF7204 1 14 P-DRIVE N-DRIVE ADP1148-3 POWER GND SIGNAL GND ...
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... 390pF 10nF C C 3300pF Figure 21. Logic Selectable 5 V 3.3 V/2 A High Efficiency Regulator REV. A ADP1148, ADP1148-3.3, ADP1148-5 IRF7204 D1 10BQ040 IRF7403 1 14 P-DRIVE N-DRIVE ADP1148 POWER GND SIGNAL GND 100pF INT V SHUTDOWN ...
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... ADP1148, ADP1148-3.3, ADP1148-5 0.210 (5.33) OUTLINE DIMENSIONS Dimensions shown in inches and (mm). 14-Lead Plastic DIP (N-14) 0.795 (20.19) 0.725 (18.42 0.280 (7.11) 0.240 (6.10 0.060 (1.52) PIN 1 0.015 (0.38) MAX 0.130 (3.30) 0.160 (4.06) MIN 0.115 (2.93) SEATING 0.022 (0.558) 0.100 0.070 (1.77) PLANE (2.54) 0.014 (0.356) 0.045 (1.15) BSC 14-Lead Plastic SO (SO-14) 0.3444 (8.75) 0.3367 (8.55) ...
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