Aimtron AT1393F 6-channel dc-dc converter ic for dsc Datasheet

AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
Features
General Description
• Low start-up power supply voltage :1.7V(CH6)
• Wide supply voltage range from 2.4V to 6.5V
(CH6); 3.6V to 6.5V(CH1~5)
• Up to 1MHz operating frequency
• Supports for down and up/down Zeta
synchronous rectification conversion(CH1)
• Supports for up and up/down SEPIC
synchronous rectification conversion(CH2, CH5)
• Supports for up, flyback and up/down SEPIC
conversion
AT1393/C: CH2,CH3, CH4 , CH5 and CH6
AT1393A/B:CH2,CH3,CH5 and CH6
• Supports for inverting conversion
AT1393A:CH4
• Synchronized rectification on CH1,CH2,CH5
• Power ON/OFF control function
• Built-in Soft-Start function
• Built-in Short-Circuit Protection circuit.
• LQFP 48 package
The AT1393 provides a complete power solution
for digital still and video cameras through the
integration of synchronous rectification topology ,
soft start function and short circuit detection
function. This IC is ideal for applications that use
either 2 or 3 alkaline or NIMH batteries as well as
those using a single Li-ion battery.
Applications
• Digital Cameras
• CCD Imaging Devices
• Camcorders
Pin Assignment
Ordering Information
Part Number
AT1393F
AT1393F_PBF
AT1393F_GRE
AT1393AF
AT1393AF_PBF
AT1393AF_GRE
Package
LQFP48
LQFP48, PB-Free
LQFP48,Green
LQFP48
LQFP48, PB-Free
LQFP48,Green
Marking
AT1393F
AT1393F,date code with one bottom line
AT1393F,date code with two bottom line
AT1393AF
AT1393AF,date code with one bottom line
AT1393AF,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
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
Pin Description
Pin No. Pin name Function
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
SWOUT
SWIN
FB6
IN6
CIN6
DTC5
FB5
IN5
INA4
OUTA4
FB4
IN4
INS4
DTC4
CS
VREF
AGND
CSCP
VCC
CTL
CTL1_ 2
CTL3
CTL4
CTL5
RT
CT
VB
IN3
FB3
DTC3
IN2
FB2
DTC2
IN1
FB1
DTC1
OUT1-1
OUT1-2
OUT2-1
OUT2-2
OUT3
PVCC
OUT4
Output Switch Control Circuit Output
Output Switch Control Circuit Input
CH6 Error Amplifier Output
CH6 Error Amplifier Inverted Input
CH6 Soft Start Setting
CH5 Dead Time Control
CH5 Error Amplifier Output
CH5 Error Amplifier Inverted Input
CH4 Inverting Amplifier Input
CH4 Inverting Amplifier Output
CH4 Error Amplifier Output
CH4 Error Amplifier Inverted Input
CH4 Short Detection Comparator Inverter Input
CH4 Dead Time Control
CH1 to CH5 Soft Start Setting
Reference 2.5V Output
Ground
Timer Latch Shout-Circuit Detection Input
Power Supply
CH6 Power Supply Control Input
CH1 and CH2 ON/OFF Control Input
CH3 ON/OFF Control Input
CH4 ON/OFF Control Input
CH5 ON/OFF Control Input
Oscillation Frequency Setting Resistor
Oscillation Frequency Setting Capacitor
Triangular Wave Oscillator Regulator Output
CH3 Error Amplifier Inverted Input
CH3 Error Amplifier Output
CH3 Dead Time Control
CH2 Error Amplifier Inverted Input
CH2 Error Amplifier Output
CH2 Dead Time Control
CH1 Error Amplifier Inverted Input
CH1 Error Amplifier Output
CH1 Dead Time Control
CH1 Main Side Output(P-CH MOSFET)
CH1 Synchronous Rectifier Side Output
CH2 Main Side Output
CH2 Synchronous Rectifier Side Output
CH3 Output(N-CH MOSFET)
Output Circuit Power Supply
CH4 Output
AT1393/C:Drive N-CH MOSFET for boost converter
AT1393A/B:Drive P-CH MOSFET for inverting
44
45
46
47
48
PGND
OUT5-1
OUT5-2
OUT6
RB
Output Circuit Ground
CH5 Main Side Output(N_CH MOSFET)
CH5 Synchronous Rectifier Side Output
CH6 Output
Output Current Setting Resistor
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
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
Absolute Maximum Ratings
Parameter
Symbol
Condition
Vcc
--
Power supply voltage
Rating
Min
Max
Unit
--
7
V
Output current
Io
Output pin
--
20
mA
Output peak current
Io
Output pin, Duty≦5%
--
200
mA
Power dissipation
PD
Ta≦25℃ (LQFP-48P)
--
860
mW
Operating temperature
TOPT
--
-30
85
℃
Storage temperature
TSTG
--
-55
125
℃
ESD Susceptibility (HBM)
--
2
KV
ESD Susceptibility (MM)
--
---
200
V
Recommended Operating Conditions
Parameter
Symbol
Condition
Min
Value
Unit
Typ Max
Startup power supply voltage
Vcc
CH6
1.7
--
5.5
V
Power supply voltage
Vcc
CH6
CH1 to CH5
2.4
3.6
5.0
5.0
5.5
5.5
V
V
Reference voltage output current
IOR
VREF pin
-1
--
0
mA
VB pin output current
IB
VB pin
-0.5
--
0
mA
IN1 to IN5, INA4, INS4
pins
0
--
Vcc
V
IN6 pin
0
--
Vcc-0.9
V
CTL pin
0
--
7
V
OUT pin (CH1 to CH5)
--
2
15
mA
OUT pin (CH6)
1
2
15
mA
OUT pin
--
1
4
mA
RB6 pin
2.4
24
51
kΩ
Input voltage
Control input voltage
Output current
VIN
VCTL
Io
Output current setting resister
RB
Oscillator
fOSC
--
100
500
1000
kHz
Timing capacitor
CT
--
47
100
560
pF
Timing resistor
RT
--
8.2
18
100
kΩ
Cs
CH1 to CH5
--
0.027
1.0
μF
CH6
--
0.47
1.0
μF
Soft start capacitor
C+IN6
Short detection capacitor
CSCP
--
--
0.1
1.0
μF
VB pin capacitor
CVB
--
0.082
0.1
--
μF
Operating ambient temperature
Ta
--
-20
25
85
℃
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
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
Electrical characteristics
(Ta=25℃, VCC=PVCC=5V)
Parameter
Reference voltage block
[REF]
Reference voltage
Output voltage
temperature
stability
Symbol
Condition
VREF
--
△VREF
Ta = -30℃ to 85℃
/VREF
Min
Value
Unit
Typ Max
2.40
2.50
2.60
V
--
0.5
--
%
--
10
mV
Load stability
Load
VREF=0mA to –1mA
-10
--
10
mV
VTH
VIN=0V to VCC
2.6
2.8
3.0
V
Hysteresis width
VH
--
0.2
--
V
Threshold voltage
Reset voltage
VRST
VIN=VCC to 0V
1.20
1.30
1.40
V
Threshold voltage
VTH
VIN=0V to VCC
1.35
1.5
1.65
V
Charge current
ICS
-1.4
-1.0
-0.6
μA
Charge current
ICIN6
-3.0
-2.5
-2.0
μA
Threshold voltage
VTH
--
0.65
0.70
0.75
V
Input standby
voltage
VSTB
--
--
50
100
mV
VI
--
--
50
100
mV
ICSCP
--
-1.4
-1.0
-0.6
μA
450
500
550
kHz
Triangular wave
oscillator block
[OSC]
Short circuit
detection block
[SCP]
Under voltage
lockout block
[U.V.L.O]
CH1 to CH5
-10
CH6
VCC=3.6 to 5.5V
Soft start
block
[CS]
Line
Soft start
block
[CIN6]
Input stability
Input latch voltage
Input source
current
Oscillator
frequency
Frequency
stability for
voltage
Frequency
stability for
temperature
Threshold voltage
VT temperature
stability
--
--
fOSC
CT=100pF, RT=18kΩ
△f
/fdv
VCC=4V to 5.5V
--
1
10
%
△f
/fdt
Ta=-30℃ to 85℃
--
1
20
%
VTH
FB=IN
1.24
1.25
1.26
V
--
0.5
--
%
△VT/VT Ta = -30℃ to 85℃
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
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
Error Amplifier block
(CH1 to CH5)
[Error Amp]
Input bias current
Error amplifier block
(CH6)
[Error Amp]
-80
--
nA
IN=0V (CH4)
-120
-30
--
nA
DC
60
100
--
dB
Frequency
bandwidth
BW
AV=0dB
--
1.0
--
MHz
Output voltage
Output source
current
Output sink
current
VOH
--
2.2
2.4
--
V
VOL
--
--
50
200
mV
--
-2.0
-1.0
mA
70
140
--
μA
ISOURCE FB=2.3V
ISINK
FB=1.45V
VTH
FB=0.55
1.24
1.25
1.26
V
△VT/VT Ta = -30℃ to 85℃
--
0.5
--
%
-100
-20
--
nA
Input bias current
IB
IN=0V
Voltage gain
AV
DC
60
75
--
dB
Frequency
bandwidth
BW
AV=0dB
--
1.0
--
MHz
Output voltage
Output source
current
Output sink
current
Input offset
voltage
Inverting amplifier block
(CH4)
[Inv Amp]
-320
AV
Temperature
stability
Short detect
comparator
(CH1 to CH5)
[SCP Comp]
IN=0V
(CH1 to CH3, CH5)
Voltage gain
Threshold voltage
Short detect
comparator
(CH6)
IB
VOH
--
1.1
1.3
--
V
VOL
--
--
0
200
mV
--
-2.0
-1.0
mA
ISOURCE FB=0.55V
ISINK
FB=0.55V
60
120
--
μA
VIO
OUT=1.25V
-10
0
10
mV
-120
-30
--
nA
Input bias current
IB
IN=0V
Voltage gain
AV
DC
60
100
--
dB
Frequency
bandwidth
BW
AV=0dB
--
1.0
--
MHz
Output voltage
Output source
current
Output sink
current
Threshold voltage
Input bias current
Threshold voltage
VOH
--
2.2
2.4
--
V
VOL
--
--
50
200
mV
--
-2.0
-1.0
mA
ISOURCE OUT=1.25V
ISINK
OUT=1.25V
70
140
--
μA
VTH
CH1 to CH5
0.97
1.00
1.03
%
IN=0V
(CH1 to CH3, CH5)
-320
-80
--
nA
IN=0V (CH4)
-200
-50
--
0.8
0.9
IB
VTH
nA
1.0
V
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
AT1393/A/B/C
Preliminary Product Information
General
Control block
(CTL, CTL1
to CTL5)
[CTL]
Output switch control block
[SW]
Output
block
(CH6)
[Drive]
Output block
(CH1 to CH5)
[Nch MOS]
Output block
(CH1,2,4,5)
[Pch MOS]
PWM Comp.
(CH6)
[PWM Comp]
PWM Comp.
(CH1 to CH5)
[PWM Comp]
6-Channel DC-DC Converter IC for DSC
Threshold voltage
Input current
Threshold voltage
Maximum duty
cycle
Output source
current
Output sink
current
Output ON
resistor
Output source
current
Output sink
current
Output ON
resistor
Output source
current
Output sink
current
SW input voltage
Input current
Output source
current
Output sink
current
Output ON
resistor
VT0
Duty = 0 %
1.0
1.1
--
V
VTmax
Duty = 100 %
--
1.8
1.9
V
IDTC
DTC=0.4V
(CH1 to CH5)
-1.0
-0.3
--
μA
VT0
Duty = 0 %
0.2
0.3
--
V
Duty = 100 %
--
0.74
0.84
V
CT=100pF, RT=18kΩ
RB=24kΩ
70
80
--
%
ISOURCE OUT=VCC/2
--
-130
--
mA
ISINK
OUT=VCC/2
--
100
--
mA
ROH
OUT = -15mA
--
18
30
Ω
ROL
OUT = 15mA
--
16
25
Ω
ISOURCE OUT=VCC/2
--
-130
--
mA
VTmax
Dtr
ISINK
OUT=VCC/2
--
100
--
mA
ROH
OUT = -15mA
--
18
30
Ω
ROL
OUT = 15mA
--
16
25
Ω
ISOURCE OUT=0.7V,RB=24kΩ
-2.6
-2.0
-1.4
mA
ISINK
Duty≦5%,OUT=0.7V
--
40
--
mA
VIH
SWOUT = ”L” level
1.5
--
6.5
V
VIL
SWOUT = ”H” level
0
--
0.4
V
ISWIN
SWIN = 5V
--
100
200
μA
ISOURCE
Duty≧95%,
SWOUT=0V
--
-9
--
mA
ISINK
Duty≦5%, SWOUT=5V
--
17
--
mA
ROH
SWOUT = -4mA
--
250
400
Ω
ROL
SWOUT = 4mA
--
100
150
Ω
VIH
Active mode
1.5
--
6.5
V
VIL
Standby mode
0
--
0.4
V
ICTL
CTL = 5V
--
100
200
μA
CTL input voltage
Input current
VCC Standby
current
PVCC Standby
current
VCC Nominal
Supply current
Icss
CTL=0V
--
--
10
μA
Icss(o)
CTL=0V
--
--
10
μA
--
6
9
mA
Icc
CTL, CTL1 to CTL5 =
5V
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
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC 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]
7
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
Application 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]om.tw
8
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC 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
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC 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]
10
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC 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]
11
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
Function Description
1. Power Converter
*Reference voltage block
A temperature independent voltage of typical value at 2.50V is generated from the
power source by the reference voltage circuit, which is used as a reference voltage
for all internal circuitry and supplies load current to external device up to 1 mA.
*Triangular oscillator block
A triangular oscillation waveform is generated by connecting a timing resistor (RT)
to pin 25 and a timing capacitor (CT) to pin 26. The resulting waveforms CT
(amplitude at 0.3V to 0.8V), CT1 (in phase with CT with amplitude at 1.1V to
1.8V) and CT2 (reverse phase with CT with amplitude at 1.1V to 1.8V) serve as
input to the PWM comparator.
*Error amplifier block
The error amplifier controls the error signal to the PWM comparator by sensing
the DC/DC converter output voltage. Furthermore, by connecting feedback
resistor and capacitor from the output pin to the inverted input pin of the error
amplifier, an arbitrary loop gain can be set to make the system stable.
*Inverting amplifier block
The inverting amplifier detects the negative DC/DC converter output voltage
and sends a control signal to the error amplifier.
*PWM comparator block
The PWM comparator converts the input voltage to pulse width and thereby the
duty cycle of the DC/DC converter.
Channels 1, 2, and 5 main sides, channel 3, 4, and 6 : The comparator keeps the
output transistor turn on while the error
amplifier output voltage and DTC voltage
are higher than the triangular wave voltage.
Channels 1, 2, and 5 synchronous rectification sides : The comparator keeps the
output transistor turn on while the error
amplifier output voltage are 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]
12
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
*Output block
A totem pole configuration is designed for the output block and can drive external
MOSFET or transistor.
2. Channel Control
The channels are turned on and turned off according to the voltage levels at the
CTL, CTL12, CTL3, CTL4, and CTL5 as described in the following table.
Voltage level at control (CTL) pin
Channel on/off status
CTL CTL1,2 CTL3 CTL4 CTL5 CH6 CH1,2 CH3
CH4
CH5
L
X
X
X
X
OFF (standby state)
L
OFF
L
OFF
H
ON
L
OFF
L
OFF
H
ON
H
ON
L
OFF
L
OFF
L
OFF
H
ON
H
ON
L
OFF
H
ON
H
ON
H
ON
L
OFF
L
OFF
H
ON
L
OFF
L
OFF
H
ON
H
ON
H
ON
L
OFF
L
OFF
H
ON
H
ON
L
OFF
H
ON
H
ON
X : Don’t care
3. Protective Functions
*Short circuit protection and timer latch
The comparator for short circuit detection in each channel detects the output
voltage level of the power converter. When the output voltage falls below the
short detection level, there will be a constant bias current charging the external
capacitor CSCP that is connected to the CSCP pin until the capacitor voltage level
reaches about 0.7V and the output transistor turned off consequently. The
actuated protection can be reset by restarting the power source.
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
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
*Under-voltage lockout protection
The under-voltage lockout protection is triggered when the supply voltage
momentarily drops during transient, which may cause the IC to malfunction. To
prevent such malfunctions, the under-voltage lockout protection circuit will turn
off the output transistor, set the dead time to 100%, and hold the CSCP pin at the
“L” level after detecting a decrease in internal reference voltage with respect to
the power supply voltage,.
*Output switch control
When the power is turned on, output switch control circuit (SWIN = “L”) prevents
the reactive current from flowing to external CH5 and CH6. After releasing
UVLO and the C+IN6 pin voltage goes above 0.9V, if SWIN is “H” then SWOUT
becomes “L” to turn on the external MOSFET and generate output 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]
14
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
4. Soft Start Function
*The CTL, CTL1,2, CTL3, CTL4, and CTL5 terminals are driven to high level at
the same time. The driving scheme is described in the following 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
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
*After CH6 soft start and driving the CTL1,2, CTL3, CTL4, and CTL5 to high
level. The driving scheme is described in following 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]
16
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
*Soft start setting (for CH6)
VC + IN ^ = 1.25 × (1 − e
−(
Ts
)
RC
)
 45K * 75K 
R=

 45K + 75K 
Consider the input voltage and the load current to decide the value of the capacitor
connected to the CIN6 pin. The soft start time Ts(s) until the DC/DC converter
output voltage of CH6 reaches 95% can be calculated by:
Ts(s) = 0.45 * C1(μF)
*Soft start setting (for CH1 to CH5)
Ts(s) = 1.25 * CS(μF)
Note : It could be disabled soft start function by floating CIN6 pin or CS pin.
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
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
Determine Oscillator Frequency
The triangular oscillator frequency is decided by the timing capacitor (CT) and
timing resistor (RT) according to the following formula:
fOSC(KHz) = 900000/( RT(KΩ)* CT(pF))
DC/DC Output Voltage
*For CH1 to CH3, CH5 and CH6
*For CH4
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
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC 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]
19
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
The CH6 Source Current
The output circuit of CH6 is illustrated in the following diagram. It can determine
the output source current by defining the value of resistor RB.
Note that the source current can be calculated by the following equation.
Output source current = (VRB/RB) * 210 (A)
Setting Time of Short Circuit Protection
The SCP comparator in each channel detects the output voltage to decide whether the
power converter works 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 become shorted, causing the output voltage to drop, the SCP
comparator detects that and enables short circuit protection. The time period for
short circuit protection is shown in the following equation.
Short detection time (tPE(s))
tPE(s) = 0.7 * CSCP (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]
20
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
Setting the Dead Time Control Level
When using step up or 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 DTC1 pin is higher than the
triangular wave voltage (CT1), the output transistor is turned on. The maximum
duty calculation formula assuming that triangular wave amplitude = 0.7V and
triangular wave minimum voltage = 1.1V.
Duty = [(Vd − 1.1) / 0.7] × 100%
Note 1 : The circuit is suitable at CH1 to CH5.
Note 2 : Shorting DTC and VREF to disable dead time control function.
Using CH4 Inv Amp.
When not using the CH4 INV Amp., connect the INA4 and OUTA4 each other.
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
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
Package Description
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]
22
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