apu3073o APEC, apu3073o Datasheet
apu3073o
Related parts for apu3073o
apu3073o Summary of contents
Page 1
... Vcc Drv2 Fb2 VcH C1 VcL U1 APU3073 HDrv REF R7 OCSet Comp LDrv Rt SS/SD R10 Fb1 Gnd PGnd R11 Figure 1 - Typical application of APU3073. DEVICE PACKAGE APU3073O 16-Pin TSSOP APU3073 12V L1 + OUT1 Q5 C10 200815061-1/17 ...
Page 2
APU3073 ABSOLUTE MAXIMUM RATINGS Vcc Supply Voltage ................................................... -0.5 - 25V VcL, VcH Supply Voltage .......................................... -0.5 - 25V Storage Temperature Range ...................................... -65°C To 150°C Operating Junction Temperature Range ..................... CAUTION: Stresses above those listed in "Absolute Maximum Ratings" ...
Page 3
PARAMETER SYM Error Amp Fb Voltage Input Bias Current I FB1 Fb Voltage Input Bias Current I FB2 V Voltage Range V P Transconductance Oscillator Frequency Freq Ramp Amplitude V RAMP Output Drivers Rise Time Tr Fall Time Tf Dead ...
Page 4
APU3073 PIN# PIN SYMBOL PIN DESCRIPTION 12 PGnd This pin serves as the separate ground for MOSFET's driver and should be connected to system's ground plane. 13 Gnd This pin serves as analog ground for internal reference and control circuitry. ...
Page 5
THEORY OF OPERATION Introduction The APU3073 is designed for a two output application and it includes one synchronous buck controller and a linear regulator controller. The PWM section is a fixed frequency, voltage mode and consists of a precision ref- ...
Page 6
APU3073 The feedback voltage increases linearly as the injecting current goes down. The injecting current drops to zero when soft-start voltage is around 2V and the output volt- age goes into steady state. As shown in Figure 4, the positive ...
Page 7
If the over-current condition is temporary and goes away quickly, the APU3073 will resume its normal operation. If output is shorted or over-current condition persists, the output voltage will keep going down until it is below 0.4V. Then the output ...
Page 8
APU3073 APPLICATION INFORMATION Design Example: The following example is a typical application for APU3073, the schematic is Figure 17 on page 16. Supply Voltage Switcher V =V L=V H=12V 2.5V OUT ...
Page 9
25%(I ), then the output inductor will be 3.125mH The Coilcraft DO5022HC series provides a range of in- ductors in different values, low profile suitable for large currents. 3.3mH is a good choice for ...
Page 10
APU3073 V DS 90% 10 (ON) (OFF Figure 9 - Switching time waveforms. From IRF7832 data sheet we obtain: IRF7832 t = 12.3ns 21ns f These values are taken ...
Page 11
V OUT Comp E Vp=V REF R Gain(dB) H(s) dB Frequency F Z Figure 11 - Compensation network without local feedback and its asymptotic gain plot. The transfer function ( ...
Page 12
APU3073 V OUT E Vp=V REF Gain(dB) H( Figure 12 - Compensation network with local feedback and ...
Page 13
LDO Section Output Voltage Programming Output voltage for LDO is programmed by reference volt- age and external voltage divider. The Fb2 pin is the in- verting input of the error amplifier, which is internally ref- erenced to 0.8V. The divider ...
Page 14
APU3073 TYPICAL APPLICATION 2.5V Q3 C13 Drv2 IRLR2703 150uF R2 1.6V Fb2 C14 R14 150uF 1K V C10 0.1uF V C2 33pF R7 C7 Comp 2200pF 24K Rt SS/SD C6 0.1uF Gnd Figure 15 - Typical application ...
Page 15
TYPICAL APPLICATION 3.3V Q3 C13 Drv2 IRLR2703 150uF R2 1.6V Fb2 C14 R14 150uF 1K V C10 0.1uF V C2 33pF R7 C7 Comp 2200pF 24K Rt SS/SD C6 0.1uF Gnd Figure 16 - Typical application of ...
Page 16
APU3073 APPLICATION EXPERIMENTAL WAVEFORMS Figure 18 - Normal condition at no load. Ch1: HDrv Ch2: LDrv Ch4: Inductor Current Figure 19 - Gate signals when SS pin pulls low. Ch1: HDrv Ch2: LDrv Figure 20 - Soft-Start. Ch1: V (5V) ...
Page 17
APPLICATION EXPERIMENTAL WAVEFORMS Figure 21 - Output Shorted at start-up. Ch1: V OUT Ch4: I OUT Figure 23 - Load Transient Response (LDO Section). Figure 22 - Load Transient Response (PWM Section). Ch1: V OUT1 Ch4: I OUT1 Ch2: V ...