AT1386 Preliminary Product Information 6-Channel DC-DC Converter for DSC Features General Description • 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 (CH 1,2,3,4,5,6) • Synchronized rectification on CH1,CH2 • Supports for negative voltage feedback CH5 • Built-in On/Off function • Built-in Soft-Start function • Built-in Short-Circuit Protection. The AT1386 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 step-up/stepdown SEPIC system with free input and output settings). 6 channels can be built in the LQFP48 package, each channel be controlled, and soft-start. Applications The AT1386 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.) • Digital Cameras • CCD Imaging Devices • Camcorders Pin Assignment Ordering Information Part number AT1386F AT1386F_PBF AT1386F_GRE Package LQFP48 LQFP48, PB-Free LQFP48, Green Marking AT1386F AT1386F, date code with one bottom line AT1386F, 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: [email protected] 1 AT1386 Preliminary Product Information 6-Channel DC-DC Converter 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 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: [email protected] 2 AT1386 Preliminary Product Information 6-Channel DC-DC Converter 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: [email protected] 3 AT1386 Preliminary Product Information 6-Channel DC-DC Converter for DSC Absolute Maximum Ratings Parameter Symbol Condition Vcc -- Power supply voltage Rating Min Max Unit -- 6.5 V Output current Io Output pin -- 30 mA Output peak current Io Output pin, Duty≦5% -- 200 mA Power dissipation PD Ta≦25℃ (LQFP-48P) -- 860 mW Operation temperature Topr -- -30 85 ℃ Storage temperature Tstg -- -55 125 ℃ *Semiconductor devices can be permanently damaged by application of stress in excess of absolute ratings. Do not exceed these ratings. Recommended Operating Conditions Value Parameter Symbol Condition Unit Min Typ Max Startup power supply voltage Vcc CH6 1.4 -- 6.0 V Power supply voltage Vcc CH1 to CH6 2.5 5.0 6.0 V Regulator voltage output current IOR VREG pin -10 -- 0 mA Input voltage VIN IN1 to IN6 pins 0 -- Vcc-1.8 V Control input voltage VCTL CTL pin 0 -- 6.0 V OUT pin (CH1 to CH5) -- 2 15 mA OUT pin (CH6) 1 2 15 mA Output current Io Oscillator fOSC -- 100 500 1000 kHz Timing capacitor CT -- 47 82 560 pF Cs CH1 to CH5 -- 0.1 1.0 μF CSS6 CH6 -- 0.1 1.0 μF Soft start capacitor Short detection capacitor CCSCP -- -- 0.1 1.0 μF VREG pin capacitor CVREG -- 0.082 0.1 -- 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: [email protected] 4 AT1386 Preliminary Product Information 6-Channel DC-DC Converter for DSC Electrical Characteristics (TA=25℃, VCC=PVCC=5V) Parameter Symbol Condition Measure result Unit Min. Typ. Max. Reference voltage block [REF] Regulator voltage Output voltage temperature stability VREG △VREF TA = -30℃ to 85℃ /VREF 2.25 2.30 2.35 V - 0.5 - % Input stability Line VCC=2.5V to 6V -80 - 80 mV Load stability Load VREG=0mA to –10mA -20 - 20 mV Under voltage lockout block [U.V.L.O] Threshold voltage(CH1~CH5) VTH 2.0 2.2 2.3 V Hysteresis width(CH1~CH5) VH1_5 0.05 0.1 0.3 V CH6 Pre-OSC change to MainOSC threshold VTH6 2.2 2.3 2.5 V Hysteresis width(CH6 Pre-OSC change to Main-OSC threshold) VH6 0.05 0.1 0.3 V fPRE-OSC 320 400 480 KHz ICS -1.5 -1.0 -0.8 μA - 0.3 - V Pre-OSC frequency Soft start block [CS] Charge current Valid Threshold voltage Short circuit detection block [SCP] Threshold voltage VTH 0.80 0.90 1.00 V Input source current ICSCP -1.5 -1.0 -0.6 μA CH1 to CH6 0.65 0.7 0.75 V IN=0V -320 -80 - nA 400 500 600 kHz Short detect comparator [SCP Comp] Threshold voltage VTH Input bias current IB Triangular wave oscillator block [OSC] Oscillator frequency fOSC CT=82pF Frequency stability for voltage △f /fdv VCC=2.5V to 6V - 1 10 % Frequency stability for temperature △f /fdt TA=-30℃ to 85℃ - 1 10 % 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: [email protected] 5 AT1386 Preliminary Product Information 6-Channel DC-DC Converter for DSC Error amplifier block [Error Amp](CH1~CH6) Threshold voltage VTH temperature stability VTH FB=IN △VT/VT TA = -30℃ to 85℃ 0.682 0.70 0.717 V - 0.5 - % Input bias current IB IN=0.7V - 80 320 nA Voltage gain AV DC - 100 - dB Frequency bandwidth BW AV=0dB - 10 - MHz VOH 0.9 1.0 1.2 V VOL - 50 200 mV - -4.0 -1.0 mA 70 140 - μA 75 85 95 % 0.25 0.3 - V - 0.80 0.85 V -1.0 -0.3 - μA - -130 -80 mA Output voltage Output source current ISOURCE FB=0.5V Output sink current ISINK FB=0.5V Maximum Duty [CH6] Maximum Duty DMAX. PWM Comp. [PWM Comp] VT0 Threshold voltage(CH1~6) Input current Duty = 0 % VTmax Duty = 100 % IDTC DTC=0.5V Output block (CH1 to CH5) [Pin 39,41,45,46,47] Output source current ISOURCE OUT=1/2VCC Output sink current Output ON resistor ISINK OUT=1/2VCC 65 100 - mA ROH OUT = -15mA - 10 25 Ω ROL OUT = 15mA - 10 25 Ω - -130 -80 mA Output block (CH1,2 ) [Pin 40,42] Output source current Output sink current Output ON resistor ISOURCE OUT=1/2VCC ISINK OUT=1/2VCC 65 100 - mA ROH OUT = -15mA - 10 25 Ω ROL OUT = 15mA - 10 25 Ω - -260 -160 mA Output block (CH6) [Pin 48] Output source current Output sink current Output ON resistor ISOURCE OUT=1/2VCC ISINK OUT=1/2VCC 130 200 - mA ROH OUT = -15mA - 10 25 Ω ROL OUT = 15mA - 10 25 Ω VIH Active mode 1.3 - VCC V Control block [CTL] CTL input 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: [email protected] 6 AT1386 Preliminary Product Information 6-Channel DC-DC Converter for DSC VIL Standby mode 0 - 0.7 V VIH Active mode 1.3 - VCC V VIL Standby mode 0 - 0.7 V ICTL CTL = 5V - 5 20 μA LBI detect threshold 1.20 1.22 1.24 V Detect Hysteresis -50 +50 mV CTL1 to CTL6 input voltage Input current Low battery detect block [LBI, LBO] LBO output voltage low Isink=1mA - - 0.4 V LBO output high leakage VLBO=5V - 0.01 1 μA - 1 10 μA - 200 250 μA - 5 7 mA - 2 2.5 mA 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 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: [email protected] 7 AT1386 Preliminary Product Information 6-Channel DC-DC Converter 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: [email protected] 8 AT1386 Preliminary Product Information 6-Channel DC-DC Converter 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: [email protected] 9 AT1386 Preliminary Product Information 6-Channel DC-DC Converter 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: [email protected] 10 AT1386 Preliminary Product Information 6-Channel DC-DC Converter 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: [email protected] 11 AT1386 Preliminary Product Information 6-Channel DC-DC Converter 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 X : Don’t care 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 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 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: [email protected] 12 AT1386 Preliminary Product Information 6-Channel DC-DC Converter for DSC 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. ＊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 circuit 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: [email protected] 13 AT1386 Preliminary Product Information 6-Channel DC-DC Converter 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: [email protected] 14 AT1386 Preliminary Product Information 6-Channel DC-DC Converter 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: [email protected] 15 AT1386 Preliminary Product Information 6-Channel DC-DC Converter 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). ∆V C× =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. 41000 f OSC ( KHz ) = 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: [email protected] 16 AT1386 Preliminary Product Information 6-Channel DC-DC Converter 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: [email protected] 17 AT1386 Preliminary Product Information 6-Channel DC-DC Converter 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: [email protected] 18 AT1386 Preliminary Product Information 6-Channel DC-DC Converter 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: [email protected] 19 AT1386 Preliminary Product Information 6-Channel DC-DC Converter 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: [email protected] 20 AT1386 Preliminary Product Information 6-Channel DC-DC Converter 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: [email protected] 21