AT1388

AT1388/AT1388A Preliminary Product Information 6-Channel DC-DC Controller for DSC Features • Low start-up power supply voltage :1.4V(CH6) • Wide supply voltage range from 2.5V to 6.5V (CH1~6) • High speed operation is possible: Maximum 1 MHz • Supports for up, flyback and up/down SEPIC conversion (AT1388:CH2,3,4,5,6 AT1388A:CH2,3,4,6) • Supports for down and up/down Zeta conversion (AT1388:CH1 AT1388A:CH1,CH5 ) • Synchronized rectification on CH1,CH2 • Supports for inverting converter CH5 • Built-in On/Off function • Built-in Soft-Start Function • Built-in Short-Circuit Protection. General Description The AT1388/AT1388A is a 6-channel PWM DC/DC control IC for low voltage applications with a soft start function and short circuit detection function. This IC is ideal for up conversion, down conversion, and up/down conversion (using a stepup/step-down SEPIC ,Zeta system with free input and output settings). 6 channels can be built in the LQFP48 package, each channel be controlled, and soft-start. The AT1388 include one comparator to generate low-battery warning outputs. It also contains two high efficiency topology by using synchronous rectification PWM(It can be disable by floating OUT1_2,OUT2_2.) Applications • Digital Cameras • CCD Imaging Devices • Camcorders Pin Assignment Ordering Information Part Number AT1388F AT1388F_PBF AT1388F_GRE AT1388AF AT1388AF_PBF AT1388AF_GRE Package LQFP48 LQFP48, PB-Free LQFP48,Green LQFP48 LQFP48, PB-Free LQFP48,Green Marking AT1388F AT1388F,date code with one bottom line AT1388F,date code with two bottom line AT1388AF AT1388AF,date code with one bottom line AT1388AF,date code with two bottom line Aimtron reserves the right without notice to change this circuitry and specifications. 2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw Fax: 886-3-563-0879 Email: service@aimtron.com.tw 1 AT1388/AT1388A Preliminary Product Information 6-Channel DC-DC Controller for DSC Pin Description Pin No. Pin name 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 SS6 FB6 IN6 DTC5 SS5 FB5 IN5N IN5P DTC4 SS4 FB4 IN4 DTC3 SS3 FB3 IN3 CTL6 CTL5 VREG AGND VCC CTL4 CT CTL CSCP CTL3 CTL2 CTL1 IN2 FB2 SS2 DTC2 IN1 FB1 SS1 DTC1 LBI LBO OUT1_1 OUT1_2 OUT2_1 OUT2_2 PVCC PGND OUT3 OUT4 OUT5 OUT6 I/O I I I I I I I I I I I I I I I I I I O P P I I I I I I I I I I I I I I O O O O O P P O O O O Function CH6 Soft Start Setting Capacitor CH6 Error Amplifier Output CH6 Error Amplifier Inverted Input CH5 Dead Time Control CH5 Soft Start Setting Capacitor CH5 Error Amplifier Output CH5 Error Amplifier Negative Input CH5 Error Amplifier Positive Input CH4 Dead Time Control CH4 Soft Start Setting Capacitor CH4 Error Amplifier Output CH4 Error Amplifier Inverted Input CH3 Dead Time Control CH3 Soft Start Setting Capacitor CH3 Error Amplifier Output CH3 Error Amplifier Inverted Input CH6 ON/OFF Control Input CH5 ON/OFF Control Input 2.3V Regulator Output Power Ground Power Supply CH4 ON/OFF Control Input Oscillation Frequency Setting Capacitor Power Control Input Timer Latch Short-Circuit Detection Capacitor Input CH3 ON/OFF Control Input CH2 ON/OFF Control Input CH1 ON/OFF Control Input CH2 Error Amplifier Inverted Input CH2 Error Amplifier Output CH2 Soft Start Setting Capacitor CH2 Dead Time Control CH1 Error Amplifier Inverted Input CH1 Error Amplifier Output CH1 Soft Start Setting Capacitor CH1 Dead Time Control Low Battery Detector Input Low Battery Indicator CH1 Main Side Output CH1 Synchronous Rectifier Side Output CH2 Main Side Output CH2 Synchronous Rectifier Side Output Drive Output Block Power Supply Drive Output Block Ground CH3 Output CH4 Output CH5 Output *AT1388: Drive N-CH MOSFET *AT1388A: Drive P-CH MOSFET CH6 Output 2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw Fax: 886-3-563-0879 Email: service@aimtron.com.tw 2 AT1388/AT1388A Preliminary Product Information 6-Channel DC-DC Controller for DSC Block Diagram 2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw Fax: 886-3-563-0879 Email: service@aimtron.com.tw 3 AT1388/AT1388A Preliminary Product Information 6-Channel DC-DC Controller for DSC Absolute Maximum Ratings Parameter Power supply voltage Output current Output peak current Power dissipation Operation temperature Storage temperature these ratings. Symbol Vcc Io Io PD Topr Tstg Condition -Output pin Output pin, Duty≦5% Ta≦25℃ (LQFP-48P) --- Rating Min Max -----30 -55 6.5 30 200 860 85 125 Unit V mA mA mW ℃ ℃ *Semiconductor devices can be permanently damaged by application of stress in excess of absolute ratings. Do not exceed Recommended Operating Conditions Value Parameter Startup power supply voltage Power supply voltage Regulator voltage output current Input voltage Control input voltage Output current Oscillator Timing capacitor Soft start capacitor Short detection capacitor VREG pin capacitor Symbol Vcc Vcc IOR VIN VCTL Io fOSC CT Cs CSS6 CCSCP CVREG CH6 CH6 Condition Min 1.4 2.5 -10 0 0 -1 100 47 -----0.082 CH1 to CH6 VREG pin IN1 to IN6 pins CTL pin OUT pin (CH1 to CH5) OUT pin (CH6) --CH1 to CH5 Unit Typ -5.0 ---2 2 500 82 0.1 0.1 0.1 0.1 Max 6.0 6.0 0 Vcc-1.8 6.0 15 15 1000 560 1.0 1.0 1.0 -V V mA V V mA mA kHz pF μF μF μF μF 2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw Fax: 886-3-563-0879 Email: service@aimtron.com.tw 4 AT1388/AT1388A Preliminary Product Information 6-Channel DC-DC Controller for DSC Electrical Characteristics (TA=25℃, VCC=PVCC=5V) Parameter Reference voltage block [REF] Regulator voltage Output voltage temperature stability Input stability Load stability Symbol VREG Condition Measure result Unit Min. Typ. Max. 2.25 -80 -20 2.30 0.5 2.35 80 20 V % mV mV △VREF TA = -30℃ to 85℃ /VREF Line Load VCC=2.5V to 6V VREG=0mA to –10mA Under voltage lockout block [U.V.L.O] Threshold voltage(CH1~CH5) Hysteresis width(CH1~CH5) CH6 Pre-OSC change to MainOSC threshold Hysteresis width(CH6 Pre-OSC change to Main-OSC threshold) Pre-OSC frequency Soft start block [CS] Charge current Valid Threshold voltage Short circuit detection block [SCP] Threshold voltage Input source current Threshold voltage Input bias current VTH ICSCP VTH IB CH1 to CH6 IN=0V 0.80 -1.5 0.65 -320 0.90 -1.0 0.7 -80 1.00 -0.6 0.75 V μA ICS -1.5 0.3 -1.0 -0.7 0.8 μA V VTH VH1_5 VTH6 VH6 fPRE-OSC 2.0 0.05 2.2 0.05 320 2.2 0.1 2.3 0.1 400 2.3 0.3 2.5 0.3 480 V V V V KHz Short detect comparator [SCP Comp] V nA Triangular wave oscillator block [OSC] Oscillator frequency Frequency stability for voltage Frequency stability for temperature fOSC △f /fdv △f /fdt CT=82pF VCC=2.5V to 6V TA=-30℃ to 85℃ 400 500 1 1 600 10 10 kHz % % Error amplifier block [Error Amp](CH1~CH6) 2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw Fax: 886-3-563-0879 Email: service@aimtron.com.tw 5 AT1388/AT1388A Preliminary Product Information 6-Channel DC-DC Controller for DSC Threshold voltage VTH temperature stability Input bias current Voltage gain Frequency bandwidth Output voltage Output source current Output sink current Maximum Duty [CH6] Maximum Duty Cycle PWM Comp. [PWM Comp] Threshold voltage(CH1~6) Input current Output source current Output sink current Output ON resistor Output block (CH1,2 ) [Pin 40,42] Output source current Output sink current Output ON resistor Output block (CH6) [Pin 48] Output source current Output sink current Output ON resistor Control block [CTL] CTL input voltage CTL1 to CTL6 input voltage VIH VIL VIH VIL Active mode Standby mode Active mode Standby mode 1.3 0 1.3 0 VCC 0.7 VCC 0.7 V V V V ISOURCE OUT=1/2VCC ISINK ROH ROL OUT=1/2VCC OUT = -15mA OUT = 15mA 130 -260 200 10 10 -160 25 25 mA mA Ω Ω ISOURCE OUT=1/2VCC ISINK ROH ROL OUT=1/2VCC OUT = -15mA OUT = 15mA 65 -130 100 10 10 -80 25 25 mA mA Ω Ω VT0 VTmax IDTC Duty = 0 % Duty = 100 % DTC=0.5V 0.25 -1.0 65 0.3 0.80 -0.3 -130 100 10 10 0.85 -80 25 25 V V μA mA mA Ω Ω DMAX 75 85 95 % VTH FB=IN 0.682 0.9 70 FB=0.5V 0.70 0.5 80 100 10 1.0 50 -4.0 140 0.717 320 1.2 200 -1.0 V % nA dB MHz V mV mA μA △VT/VT TA = -30℃ to 85℃ IB AV BW VOH VOL ISOURCE FB=0.5V ISINK IN=0.7V DC AV=0dB Output block (CH1 to CH5) [Pin 39,41,45,46,47] ISOURCE OUT=1/2VCC ISINK ROH ROL OUT=1/2VCC OUT = -15mA OUT = 15mA 2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw Fax: 886-3-563-0879 Email: service@aimtron.com.tw 6 AT1388/AT1388A Preliminary Product Information 6-Channel DC-DC Controller for DSC Input current LBI detect threshold LBO output voltage low LBO output high leakage General(Output no Load) CTL=CTL1=CTL2=CTL 3=CTL4=CTL5=CTL6=0 V CTL=0V, Icss(o) CTL1=CTL2=CTL3=CT L4=CTL5=CTL6="H" CTL=CTL1=CTL2=CTL Icc1 3=CTL4=CTL5=CTL6=" H" CTL=”H” Icc2 CTL1=CTL2=CTL3=CT L4=CTL5=CTL6="L" Icss 1 200 5 2 10 250 7 2.5 μA μA mA mA ICTL CTL = 5V 5 20 μA Low battery detect block [LBI, LBO] VTHLBI Rising Isink=1mA VLBO=5V 1.2397 1.2650 1.2903 0.01 0.4 1 V V μA Standby current Power supply current Power supply current 2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw Fax: 886-3-563-0879 Email: service@aimtron.com.tw 7 AT1388/AT1388A Preliminary Product Information 6-Channel DC-DC Controller for DSC Application Circuit (2 Cell Battery 1.5V~3.4V input) 2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw Fax: 886-3-563-0879 Email: service@aimtron.com.tw 8 AT1388/AT1388A Preliminary Product Information 6-Channel DC-DC Controller for DSC 2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw Fax: 886-3-563-0879 Email: service@aimtron.com.tw 9 AT1388/AT1388A Preliminary Product Information 6-Channel DC-DC Controller for DSC 2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw Fax: 886-3-563-0879 Email: service@aimtron.com.tw 10 AT1388/AT1388A Preliminary Product Information 6-Channel DC-DC Controller for DSC Application Circuit (2 Cell Battery 1.5V~3.4V input) 2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw Fax: 886-3-563-0879 Email: service@aimtron.com.tw 11 AT1388/AT1388A Preliminary Product Information 6-Channel DC-DC Controller for DSC 2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw Fax: 886-3-563-0879 Email: service@aimtron.com.tw 12 AT1388/AT1388A Preliminary Product Information 6-Channel DC-DC Controller for DSC 2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw Fax: 886-3-563-0879 Email: service@aimtron.com.tw 13 AT1388/AT1388A Preliminary Product Information 6-Channel DC-DC Controller for DSC Function Description 1. Power Converter Functions ＊Reference voltage block The reference voltage circuit generates a temperature independence voltage (typical=2.3V) from the power source, which is used as reference voltage for the IC’s internal circuitry and supply load current above 10mA to external device. ＊Triangular oscillator block The triangular wave oscillator is generated by timing capacitor(CT) to incorporate each other. The waveforms CT (amplitude of 0.3V to 0.8V), CTP (amplitude 0.3V to 0.8V in phase with CT) and CTN (amplitude 0.3V to 0.8V in inverse phase with CT) are input to the PWM comparator. ＊Error amplifier block The error amplifier outputs controlling error signal to PWM comparator from sensing DC/DC converter output voltage. In addition, an arbitrary loop gain can be set by connecting feedback resistor and capacitor from the output pin to inverted input pin of the error amplifier, in order to make a stable system. ＊CH5 Inverting amplifier block The inverting amplifier detects the DC/DC converter output voltage (negative) and outputs a control signal to the error amplifier. ＊PWM comparator block The PWM comparator is a voltage-to-pulse width converter for controlling the duty cycle of DC/DC converter. Channels 1, 2 main sides, channel 3, 4, 5, and 6 : The comparator keeps the output transistor turn on while the error amplifier output voltage and DTC voltage still higher than the triangular wave voltage. Channels 1, 2 synchronous rectification sides : The comparator keeps the output transistor turn on while the error amplifier output voltage still lower than the triangular wave voltage. 2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw Fax: 886-3-563-0879 Email: service@aimtron.com.tw 14 AT1388/AT1388A Preliminary Product Information 6-Channel DC-DC Controller for DSC ＊Output block The output block is the totem pole configuration, which could drive external MOSFET or transistor. 2. Channel Control Function The channels are turned on and turned off depending on the voltage levels at the CTL, CTL12, CTL3, CTL4, CTL5, and CTL6. Described as follow. CTL CTL1 CTL2 CTL3 CTL4 CTL5 CTL6 CH1 CH2 CH3 CH4 CH5 CH6 L X X X X X X OFF H H Z Z Z Z Z ON OFF OFF OFF OFF OFF Z H Z Z Z Z OFF ON OFF OFF OFF OFF Z Z H Z Z Z OFF OFF ON OFF OFF OFF Z Z Z H Z Z OFF OFF OFF ON OFF OFF Z Z Z Z H Z OFF OFF OFF OFF ON OFF Z Z Z Z Z H OFF OFF OFF OFF OFF ON X : Don’t care Z: Low or Floating 3. Protective Functions ＊Short circuit protection and timer latch The short circuit detection comparator in each channel detects the output voltage level of power converter. When the output voltage falls below the short detection level, there is a constant current bias charging the external capacitor CCSCP which connected to the CSCP pin until the capacitor voltage level reaches about 0.7V then disable the IC. It could reset the actuated protection by restart the power source or pull CTL from low to high. ＊Under-voltage lockout protection The under-voltage lockout protection is to disable the IC while the supply voltage transient or momentary decrease, which may cause the IC to malfunction. To prevent such malfunctions, the under-voltage lockout protection circuit detects a decrease in internal reference voltage with respect to the power supply voltage, turns off the output transistor, and holding the CSCP pin at the “L” level. 2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw Fax: 886-3-563-0879 Email: service@aimtron.com.tw 15 AT1388/AT1388A Preliminary Product Information 6-Channel DC-DC Controller for DSC ＊Battery Low Detect Function The Battery low comparator open-drain output LBO sinks up to 1mA if the LBI input is below its threshold voltage. Connect LBO to power source with a 100KΩ~1MΩ pull-up resistor. 4. Negative Voltage Feedback 2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw Fax: 886-3-563-0879 Email: service@aimtron.com.tw 16 AT1388/AT1388A Preliminary Product Information 6-Channel DC-DC Controller for DSC 5. Soft Start Operation ＊The CTL, CTL1,2, CTL3, CTL4, CTL5 and CTL6 terminals are driven high level at the same time. The driving scheme is described as follow diagram. 2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw Fax: 886-3-563-0879 Email: service@aimtron.com.tw 17 AT1388/AT1388A Preliminary Product Information 6-Channel DC-DC Controller for DSC ＊After CTL ON, driving the CTL1, CTL2, CTL3, CTL4, CTL5 and CTL6 to high level. The driving scheme is described as follow diagram. 2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw Fax: 886-3-563-0879 Email: service@aimtron.com.tw 18 AT1388/AT1388A Preliminary Product Information 6-Channel DC-DC Controller for DSC ＊Soft start setting (CH1~6) Consider the input voltage and load current to design the capacitor connected to the SS pin. It can calculate the CH1~6 soft start time Ts(s)(valid threshold 0.3~0.8V interval). C× ∆V =I ∆t Ts( s ) = 0.5 × C ( µF ) Note : It could be disabled soft start function by floating SS pin. Determine the triangular Oscillator Frequency The triangular oscillator frequency is determined by the timing capacitor (CT). It is difficult to incorporate these non-linear characteristics into the equation. This difference is caused by characteristics, such as changes in the maximum voltage amplitude of the sawtooth waveform with the CT value and the circuit delay causing the maximum amplitude to become large in the case of a high oscillating frequency even for the same capacitor. In practical use, therefore, the user should read the CT values from the characteristic curve or should determine an approximate target value by using the equation. f OSC ( KHz ) = 41000 CT ( pF ) 2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw Fax: 886-3-563-0879 Email: service@aimtron.com.tw 19 AT1388/AT1388A Preliminary Product Information 6-Channel DC-DC Controller for DSC Design the DC/DC Output Voltage ＊CH1~6 Setting Time Period When Short Circuit Protection The CSCP comparator detects each channel output voltage while the power converter work at normal condition. At the same time, the voltage level of CSCP pin is held at low level. If the output load of these converters rapidly malfunction or short, causing the output voltage to drop, the CSCP comparator detects that to enable short circuit protection. The time period when short circuit protection show as follow equation. Short detection time (TPE(s)) TPE(s) = 0.7 * CCSCP (μF) Note : It could be disabled short circuit protection function by connecting CSCP pin into the ground. 2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw Fax: 886-3-563-0879 Email: service@aimtron.com.tw 20 AT1388/AT1388A Preliminary Product Information 6-Channel DC-DC Controller for DSC Setting the Dead Time Control Level When using Boost, SEPIC, Zeta or flyback DC/DC converter, it must prevent that output transistor works at full-ON state (ON duty = 100%). To prevent this situation, set the maximum duty of these channels. The dead time control circuit is implemented as below. When the voltage at the DTC pin is higher than the triangular wave voltage (CT, CTP, CTN), the output transistor is turned on. The maximum duty calculation formula assuming that triangular wave amplitude = 0.5V and triangular wave minimum voltage = 0.3V. Duty MAX . = ( Vd − 0.3 ) × 100% 0.5 Note 1 : The circuit is suitable at CH1 to CH5. Note 2 : Shorting DTC and VREG to disable dead time control function. 2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw Fax: 886-3-563-0879 Email: service@aimtron.com.tw 21 AT1388/AT1388A Preliminary Product Information 6-Channel DC-DC Controller for DSC Typical Characteristics 2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw Fax: 886-3-563-0879 Email: service@aimtron.com.tw 22 AT1388/AT1388A Preliminary Product Information 6-Channel DC-DC Controller for DSC 2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw Fax: 886-3-563-0879 Email: service@aimtron.com.tw 23 AT1388/AT1388A Preliminary Product Information 6-Channel DC-DC Controller for DSC Package Outline LQFP48 2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C. Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw Fax: 886-3-563-0879 Email: service@aimtron.com.tw 24