19-3711; Rev 0; 5/05
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PART
PINTEMP RANGE
PACKAGE
MAX8732AEEI+ -40°C to +85°C 28 QSOP
MAX8732AEEI
-40°C to +85°C 28 QSOP
5V/3.3V
SWITCHING
FREQUENCY
(kHz)
200/300
200/300
MAX8733AEEI+ -40°C to +85°C 28 QSOP
400/500
MAX8733AEEI
400/500
-40°C to +85°C 28 QSOP
ࢾ৪ቧᇦ)ኚ*Ᏼၫᓾ೯ࡼᔢઁ߲ă
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````````````````````````````````୭ᒙ
TOP VIEW
N.C. 1
28 BST3
PGOOD 2
27 LX3
ON3 3
26 DH3
ON5 4
25 LDO3
ILIM3 5
SHDN 6
24 DL3
MAX8734A
23 GND
FB3 7
22 OUT3
REF 8
21 OUT5
FB5 9
20 V+
PRO 10
19 DL5
ILIM5 11
18 LDO5
SKIP 12
17 VCC
TON 13
16 DH5
BST5 14
15 LX5
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QSOP
୭ᒙ)ኚ*Ᏼၫᓾ೯ࡼᔢઁ߲ă
________________________________________________________________ Maxim Integrated Products
1
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NBY9843B0NBY9844B0NBY9845B
````````````````````````````````````গၤ
NBY9843B0NBY9844B0NBY9845B
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ABSOLUTE MAXIMUM RATINGS
V+, SHDN to GND ..................................................-0.3V to +25V
BST_ to GND ..........................................................-0.3V to +30V
LX_ to BST_ ..............................................................-6V to +0.3V
CS_ to GND (MAX8732A/MAX8733A only) .................-2V to +6V
VCC, LDO5, LDO3, OUT3, OUT5, ON3, ON5, REF,
FB3, FB5, SKIP, PRO, PGOOD to GND ...............-0.3V to +6V
DH3 to LX3 ..............................................-0.3V to (VBST3 + 0.3V)
DH5 to LX5 ..............................................-0.3V to (VBST5 + 0.3V)
ILIM3, ILIM5 to GND...................................-0.3V to (VCC + 0.3V)
DL3, DL5 to GND....................................-0.3V to (VLDO5 + 0.3V)
TON to GND (MAX8734A only) ................................-0.3V to +6V
LDO3, LDO5, REF Short Circuit to GND ....................Momentary
LDO3 Current (internal regulator) Continuous................+100mA
LDO3 Current (switched over to OUT3) Continuous ......+200mA
LDO5 Current (internal regulator) Continuous................+100mA
LDO5 Current (switched over to OUT5) Continuous ......+200mA
Continuous Power Dissipation (TA = +70°C)
28-Pin QSOP (derate 10.8mW/°C above +70°C).........860mW
Operating Temperature Range ...........................-40°C to +85°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(Circuit of Figure 1 and Figure 2, no load on LDO5, LDO3, OUT3, OUT5, and REF, V+ = 12V, ON3 = ON5 = VCC, V SHDN = 5V,
TA = 0°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.)
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
MAIN SMPS CONTROLLERS
V+ Input Voltage Range
3.3V Output Voltage in
Fixed Mode
5V Output Voltage in Fixed Mode
LDO5 in regulation
V+ = LDO5, VOUT5 < 4.43V
V+ = 6V to 24V, FB3 = GND, V SKIP = 5V
V+ = 6V to 24V, FB5 = GND, V SKIP = 5V,
MAX8732A/MAX8734A (TON = VCC)
6
24
4.5
5.5
V
3.285
3.330
3.375
V
4.975
5.050
5.125
V
1.975
2.00
2.025
V
V+ = 7V to 24V, FB5 = GND, V SKIP = 5V,
MAX8733A/MAX8734A (TON = GND)
Output Voltage in
Adjustable Mode
V+ = 6V to 24V, either SMPS
Output Voltage Adjust Range
Either SMPS
2.0
5.5
V
FB3, FB5 Adjustable-Mode
Threshold Voltage
Dual-Mode comparator
0.1
0.2
V
DC Load Regulation
Either SMPS, V SKIP = 5V, 0 to 5A
-0.1
Either SMPS, SKIP = GND, 0 to 5A
-1.5
Either SMPS, V SKIP = 2V, 0 to 5A
-1.7
%
Line Regulation
Either SMPS, 6V < V+ < 24V
Current-Limit Threshold
(Positive, Default)
ILIM_ = VCC, GND - CS_ (MAX8732A/MAX8733A),
GND - LX_ (MAX8734A)
Current-Limit Threshold
(Positive, Adjustable)
GND - CS_
(MAX8732A/MAX8733A),
GND - LX_ (MAX8734A)
Zero-Current Threshold
SKIP = GND, ILIM_ = VCC, GND - CS_
(MAX8732A/MAX8733A), GND - LX_ (MAX8734A)
3
mV
Current-Limit Threshold
(Negative, Default)
SKIP = ILIM_ = VCC, GND - CS_
(MAX8732A/MAX8733A), GND - LX_ (MAX8734A)
-120
mV
Soft-Start Ramp Time
Zero to full limit
1.7
ms
2
0.005
93
100
%/V
107
VILIM_ = 0.5V
40
50
60
VILIM_ = 1V
93
100
107
VILIM_ = 2V
185
200
215
_______________________________________________________________________________________
mV
mV
᎖܊࢟۾ฎࡼൈĂ
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(Circuit of Figure 1 and Figure 2, no load on LDO5, LDO3, OUT3, OUT5, and REF, V+ = 12V, ON3 = ON5 = VCC, V SHDN = 5V,
TA = 0°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.)
PARAMETER
Operating Frequency
CONDITIONS
200
3.3V SMPS
300
MAX8733A or MAX8734A
(VTON = 0), SKIP = VCC
5V SMPS
400
3.3V SMPS
500
MAX8732A or MAX8734A
(VTON = 5V)
MAX8733A or MAX8734A
(VTON = 0)
MAX8732A or MAX8734A
(VTON = 5V)
MAX8733A or MAX8734A
(VTON = 0)
MAX
25
36
1.895
2.105
2.315
VOUT3 = 3.33V
0.833
0.925
1.017
VOUT5 = 5.05V
0.895
1.052
1.209
VOUT3 = 3.33V
0.475
0.555
0.635
250
300
350
VOUT5 = 5.05V
94
VOUT3 = 3.33V
91
VOUT5 = 5.05V
88
VOUT3 = 3.33V
INTERNAL REGULATOR AND REFERENCE
LDO5 Output Voltage
ON3 = ON5 = GND, 6V < V+ < 24V, 0 < ILDO5 < 100mA
UNITS
kHz
VOUT5 = 5.05V
Minimum Off-Time
Maximum Duty Cycle
TYP
5V SMPS
SKIP = REF
On-Time Pulse Width
MIN
MAX8732A or MAX8734A
(VTON = 5V), SKIP = VCC
μs
ns
%
85
4.90
5.00
5.10
190
V
LDO5 Short-Circuit Current
LDO5 = GND
LDO5 Undervoltage-Lockout
Fault Threshold
Falling edge of LDO5, hysteresis = 1%
3.7
4.0
4.3
V
LDO5 Bootstrap Switch Threshold
Falling edge of OUT5, rising edge at OUT5 regulation
point
4.43
4.56
4.69
V
LDO5 Bootstrap
Switch Resistance
LDO5 to OUT5, VOUT5 = 5V
1.4
3.2
Ω
3.35
3.42
3.28
mA
LDO3 Output Voltage
ON3 = ON5 = GND, 6V < V+ < 24V, 0 < ILDO3 < 100mA
LDO3 Short-Circuit Current
LDO3 = GND
LDO3 Bootstrap Switch Threshold
Falling edge of OUT3, rising edge at OUT3 regulation
point
LDO3 Bootstrap Switch
Resistance
LDO3 to OUT3, VOUT3 = 3.2V
REF Output Voltage
No external load
REF Load Regulation
0 < ILOAD < 50μA
REF Sink Current
REF in regulation
V+ Operating Supply Current
LDO5 switched over to OUT5, 5V SMPS
25
50
V+ Standby Supply Current
V+ = 6V to 24V, both SMPSs off, includes ISHDN
150
250
μA
V+ Shutdown Supply Current
V+ = 4.5V to 24V
6
15
μA
Quiescent Power Consumption
Both SMPSs on, FB3 = FB5 = SKIP = GND, VOUT3 =
3.5V, VOUT5 = 5.3V
3
4.5
mW
+11
+14
%
180
2.80
1.980
V
mA
2.91
3.02
V
1.5
3.5
Ω
2.000
2.020
V
10
mV
10
μA
μA
FAULT DETECTION
Overvoltage Trip Threshold
FB3 or FB5 with respect to nominal regulation point
+8
_______________________________________________________________________________________
3
NBY9843B0NBY9844B0NBY9845B
ELECTRICAL CHARACTERISTICS (continued)
NBY9843B0NBY9844B0NBY9845B
᎖܊࢟۾ฎࡼൈĂ
႐ၒ߲ᓍ࢟Ꮞ఼ᒜ
ELECTRICAL CHARACTERISTICS (continued)
(Circuit of Figure 1 and Figure 2, no load on LDO5, LDO3, OUT3, OUT5, and REF, V+ = 12V, ON3 = ON5 = VCC, V SHDN = 5V,
TA = 0°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.)
PARAMETER
CONDITIONS
Overvoltage Fault
Propagation Delay
FB3 or FB5 delay with 50mV overdrive
PGOOD Threshold
FB3 or FB5 with respect to nominal output, falling edge,
typical hysteresis = 1%
PGOOD Propagation Delay
Falling edge, 50mV overdrive
PGOOD Output Low Voltage
ISINK = 4mA
PGOOD Leakage Current
High state, forced to 5.5V
MIN
TYP
MAX
10
-12
-9.5
μs
-7
10
Thermal-Shutdown Threshold
UNITS
%
μs
0.3
V
1
μA
o
+160
C
Output Undervoltage
Shutdown Threshold
FB3 or FB5 with respect to nominal output voltage
65
70
75
%
Output Undervoltage
Shutdown Blanking Time
From ON_ signal
10
22
35
ms
-200
+40
+200
nA
INPUTS AND OUTPUTS
Feedback Input Leakage Current
PRO Input Voltage
VFB3 = VFB5 = 2.2V
Low level
High level
0.6
1.5
Low level
SKIP Input Voltage
TON Input Voltage
0.8
Float level
1.7
High level
2.4
2.3
Low level
High level
0.8
2.4
Clear fault level/SMPS off level
ON3, ON5 Input Voltage
Input Leakage Current
SHDN Input Trip Level
V
V
V
0.8
Delay start level
1.7
SMPS on level
2.4
2.3
V PRO or VTON = 0 or 5V
-1
+1
VON_ = 0 or 5V
-2
+2
V SKIP = 0 or 5V
-1
+1
V SHDN = 0 or 24V
-1
+1
VCS_ = 0 or 5V
-2
+2
VILIM3, VILIM5 = 0 or 2V
-0.2
Rising edge
1.2
1.6
2.0
Falling edge
0.96
1.00
1.04
V
μA
+0.2
V
DH_ Gate-Driver
Sink/Source Current
DH3, DH5 forced to 2V
DL_ Gate-Driver Source Current
DL3 (source), DL5 (source), forced to 2V
1.7
A
DL_ Gate-Driver Sink Current
DL3 (sink), DL5 (sink), forced to 2V
3.3
A
DH_ Gate-Driver On-Resistance
BST - LX_ forced to 5V
1.5
4.0
DL_, high state (pullup)
2.2
5.0
DL_, low state (pulldown)
0.6
1.5
DL_ Gate-Driver On-Resistance
4
2
_______________________________________________________________________________________
A
Ω
Ω
᎖܊࢟۾ฎࡼൈĂ
႐ၒ߲ᓍ࢟Ꮞ఼ᒜ
(Circuit of Figure 1 and Figure 2, no load on LDO5, LDO3, OUT3, OUT5, and REF, V+ = 12V, ON3 = ON5 = VCC, V SHDN = 5V,
TA = 0°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.)
PARAMETER
CONDITIONS
MIN
OUT3, OUT5 Discharge-Mode
On-Resistance
OUT3, OUT5 Discharge-Mode
Synchronous Rectifier
Turn-On Level
0.2
TYP
MAX
UNITS
12
40
Ω
0.3
0.4
V
ELECTRICAL CHARACTERISTICS
(Circuit of Figure 1 and Figure 2, no load on LDO5, LDO3, OUT3, OUT5, and REF, V+ = 12V, ON3 = ON5 = VCC, V SHDN = 5V,
TA = -40°C to +85°C, unless otherwise noted.) (Note 1)
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
MAIN SMPS CONTROLLERS
V+ Input Voltage Range
3.3V Output Voltage in
Fixed Mode
5V Output Voltage in Fixed Mode
LDO5 in regulation
6
24
V+ = LDO5, VOUT5 < 4.41V
4.5
5.5
V+ = 6V to 24V, FB3 = GND, V SKIP = 5V
3.27
3.39
V
4.95
5.15
V
V+ = 6V to 24V, FB5 = GND, V SKIP = 5V,
MAX8732A/MAX8734A (TON = VCC)
V
V+ = 7V to 24V, FB5 = GND, V SKIP = 5V,
MAX8733A/MAX8734A (TON = GND)
Output Voltage in
Adjustable Mode
V+ = 6V to 24V, either SMPS
1.97
2.03
V
Output Voltage Adjust Range
Either SMPS
2.0
5.5
V
FB3, FB5 Adjustable-Mode
Threshold Voltage
Dual-Mode comparator
0.1
0.2
V
Current-Limit Threshold
(Positive, Default)
ILIM_ = VCC, GND - CS_ (MAX8732A/MAX8733A),
GND - LX_ (MAX8734A)
90
110
mV
GND - CS_
(MAX8732A/MAX8733A),
GND - LX_ (MAX8734A)
40
60
Current-Limit Threshold
(Positive, Adjustable)
VILIM_ = 1V
90
110
VILIM_ = 2V
180
220
On-Time Pulse Width
VILIM_ = 0.5V
mV
MAX8732A or MAX8734A
(VTON = 5V)
VOUT5 = 5.05V
1.895
2.315
VOUT3 = 3.33V
0.833
1.017
MAX8733A or MAX8734A
(VTON = 0)
VOUT5 = 5.05V
0.895
1.209
VOUT3 = 3.33V
0.475
0.635
200
400
ns
Minimum Off-Time
μs
INTERNAL REGULATOR AND REFERENCE
LDO5 Output Voltage
ON3 = ON5 = GND, 6V < V+ < 24V, 0 < ILDO5 < 100mA
4.90
5.10
V
LDO5 Undervoltage-Lockout
Fault Threshold
Falling edge of LDO5, hysteresis = 1%
3.7
4.3
V
_______________________________________________________________________________________
5
NBY9843B0NBY9844B0NBY9845B
ELECTRICAL CHARACTERISTICS (continued)
NBY9843B0NBY9844B0NBY9845B
᎖܊࢟۾ฎࡼൈĂ
႐ၒ߲ᓍ࢟Ꮞ఼ᒜ
ELECTRICAL CHARACTERISTICS (continued)
(Circuit of Figure 1 and Figure 2, no load on LDO5, LDO3, OUT3, OUT5, and REF, V+ = 12.0.V, ON3 = ON5 = VCC, V SHDN = 5V,
TA = -40°C to +85°C, unless otherwise noted.) (Note 1)
PARAMETER
CONDITIONS
LDO5 Bootstrap Switch Threshold
Falling edge of OUT5, rising edge at OUT5 regulation
point
LDO5 Bootstrap Switch
Resistance
LDO5 to OUT5, VOUT5 = 5V
LDO3 Output Voltage
ON3 = ON5 = GND, 6V < V+ < 24V, 0 < ILDO3 < 100mA
Falling edge of OUT3, rising edge at OUT3 regulation
LDO3 Bootstrap Switch Threshold
point
MIN
TYP
MAX
UNITS
4.69
V
3.2
Ω
3.27
3.43
V
2.80
3.02
V
3.5
Ω
2.025
V
10
mV
4.43
LDO3 Bootstrap
Switch Resistance
LDO3 to OUT3, VOUT3 = 3.2V
REF Output Voltage
No external load
REF Load Regulation
0 < ILOAD < 50μA
REF Sink Current
REF in regulation
V+ Operating Supply Current
LDO5 switched over to OUT5, 5V SMPS
50
μA
V+ Standby Supply Current
V+ = 6V to 24V, both SMPSs off, includes ISHDN
300
μA
V+ Shutdown Supply Current
V+ = 4.5V to 24V
15
μA
Quiescent Power Consumption
Both SMPSs on, FB3 = FB5 = SKIP = GND, VOUT3 =
3.5V, VOUT5 = 5.3V
4.5
mW
1.975
10
μA
FAULT DETECTION
Overvoltage Trip Threshold
FB3 or FB5 with respect to nominal regulation point
+8
+14
%
PGOOD Threshold
FB3 or FB5 with respect to nominal output, falling edge,
typical hysteresis = 1%
-12
-7
%
PGOOD Output Low Voltage
ISINK = 4mA
PGOOD Leakage Current
High state, forced to 5.5V
Output Undervoltage Shutdown
Threshold
FB3 or FB5 with respect to nominal output voltage
Output Undervoltage Shutdown
Blanking Time
From ON_ signal
0.3
V
1
μA
65
75
%
10
40
ms
-200
+200
nA
INPUTS AND OUTPUTS
Feedback Input Leakage Current
PRO Input Voltage
VFB3 = VFB5 = 2.2V
Low level
High level
0.6
1.5
Low level
SKIP Input Voltage
TON Input Voltage
6
0.8
Float level
1.7
High level
2.4
Low level
High level
V
2.3
0.8
2.4
_______________________________________________________________________________________
V
V
᎖܊࢟۾ฎࡼൈĂ
႐ၒ߲ᓍ࢟Ꮞ఼ᒜ
(Circuit of Figure 1 and Figure 2, no load on LDO5, LDO3, OUT3, OUT5, and REF, V+ = 12.0.V, ON3 = ON5 = VCC, V SHDN = 5V,
TA = -40°C to +85°C, unless otherwise noted.) (Note 1)
PARAMETER
CONDITIONS
MIN
Clear fault level/SMPS off level
ON3, ON5 Input Voltage
Input Leakage Current
DL_ Gate-Driver On-Resistance
SMPS on level
2.4
V PRO or VTON = 0 or 5V
-1
+1
VON_ = 0 or 5V
-1
+1
V SKIP = 0 or 5V
-2
+2
V SHDN = 0 or 24V
-1
+1
2.3
-2
+2
-0.2
+0.2
Rising edge
1.2
2.0
Falling edge
0.96
1.04
BST - LX_ forced to 5V
4.0
DL_, high state (pullup)
5.0
DL_, low state (pulldown)
1.5
OUT3, OUT5 Discharge-Mode
On-Resistance
OUT3, OUT5 Discharge-Mode
Synchronous Rectifier
Turn-On Level
UNITS
0.8
1.7
VCS_ = 0 or 5V
DH_ Gate-Driver On-Resistance
MAX
Delay start level
VILIM3, VILIM5 = 0 or 2V
SHDN Input Trip Level
TYP
0.2
V
μA
V
Ω
Ω
40
Ω
0.4
V
Note 1: Specifications to -40°C are guaranteed by design, not production tested.
_______________________________________________________________________________________
7
NBY9843B0NBY9844B0NBY9845B
ELECTRICAL CHARACTERISTICS (continued)
```````````````````````````````````````````````````````````````````````࢜ቯᔫᄂቶ
(Circuit of Figure 1 and Figure 2, no load on LDO5, LDO3, OUT3, OUT5, and REF, V+ = 12V, ON3 = ON5 = VCC, SHDN = V+,
RCS = 7mΩ, VILIM_ = 0.5V, TA = +25°C, unless otherwise noted.)
40
30
PWM MODE
60
50
ULTRASONIC MODE
40
20
VIN = 7V
ON5 = VCC
ON3 = GND
10
1
10
0.01
LOAD CURRENT (A)
MAX8733A
3.3V OUTPUT EFFICIENCY
vs. LOAD CURRENT
90
80
70
60
ULTRASONIC MODE
50
40
30
20
PWM MODE
10
ON5 = VCC
ON3 = VCC
VIN = 7V
VIN = 12V
VIN = 24V
0.1
1
PFM MODE
7
10
188
186
184
MAX8732A
182
180
178
176
MAX8733A
174
172
13
16
19
22
PWM MODE
10
13
16
19
INPUT VOLTAGE (V)
22
25
PFM MODE
10
7
13
16
19
22
MAX8732A
5V OUTPUT SWITCHING FREQUENCY
vs. LOAD CURRENT MAX8732A
9.0
MAX8732A
8.0
MAX8733A
7.5
7.0
6.5
6.0
250
225
VIN = 7V
200
175
25
PWM MODE
150
125
100
75
50
ULTRASONIC MODE
25
5.0
7
1
0.1
25
5.5
170
ULTRASONIC MODE
SHUTDOWN INPUT CURRENT
vs. INPUT VOLTAGE
9.5
8.5
10
INPUT VOLTAGE (V)
10.0
SHUTDOWN INPUT CURRENT (μA)
MAX8732A/3A/4A toc07
190
STANDBY INPUT CURRENT (μA)
100
INPUT VOLTAGE (V)
LOAD CURRENT (A)
STANDBY INPUT CURRENT
vs. INPUT VOLTAGE
10
MAX8733A
NO-LOAD BATTERY CURRENT
vs. INPUT VOLTAGE
1
10
1
MAX8732A
NO-LOAD BATTERY CURRENT
vs. INPUT VOLTAGE
SWITCHING FREQUENCY (kHz)
0.01
0.1
LOAD CURRENT (A)
ULTRASONIC MODE
10
0.01
LOAD CURRENT (A)
MAX8732A/3A/4A toc08
0.001
VIN = 24V
ON5 = VCC
ON3 = GND
0.001
10
0.1
0
8
1
PWM MODE
BATTERY CURRENT (mA)
PFM MODE
0.1
100
MAX8732A/3A/4A toc04
100
ULTRASONIC MODE
40
0
0.001
BATTERY CURRENT (mA)
0.1
MAX8732A/3A/4A toc05
0.01
50
10
0
0.001
PWM MODE
60
20
VIN = 12V
ON5 = VCC
ON3 = GND
10
0
70
30
30
20
PFM MODE
80
MAX8732A/3A/4A toc06
ULTRASONIC MODE
50
70
90
MAX8732A/3A/4A toc09
60
100
EFFICIENCY (%)
PWM MODE
80
EFFICIENCY (%)
EFFICIENCY (%)
80
PFM MODE
90
MAX8732A
5V OUTPUT EFFICIENCY
vs. LOAD CURRENT
MAX8732A/3A/4A toc02
PFM MODE
90
70
100
MAX8732A/3A/4A toc01
100
MAX8732A
5V OUTPUT EFFICIENCY
vs. LOAD CURRENT
MAX8732A/3A/4A toc03
MAX8732A
5V OUTPUT EFFICIENCY
vs. LOAD CURRENT
EFFICIENCY (%)
NBY9843B0NBY9844B0NBY9845B
᎖܊࢟۾ฎࡼൈĂ
႐ၒ߲ᓍ࢟Ꮞ఼ᒜ
7
10
13
16
19
INPUT VOLTAGE (V)
22
25
0
0.001
PFM MODE
0.01
0.1
LOAD CURRENT (A)
Jemf! NpefဵNbyjn! Joufhsbufe! Qspevdut-! Jod/ࡼܪă
_______________________________________________________________________________________
1
10
᎖܊࢟۾ฎࡼൈĂ
႐ၒ߲ᓍ࢟Ꮞ఼ᒜ
MAX8732A
5V OUTPUT SWITCHING
FREQUENCY vs. LOAD CURRENT
200
160
120
ULTRASONIC MODE
40
0.1
1
PFM MODE
0
0.01
0.1
1
10
0.001
500
350
300
250
200
150
0.01
0.1
1
0
0.1
1
0
0.001
10
450
10
350
PWM MODE
300
250
200
150
100
ULTRASONIC MODE
50
PFM MODE
0.01
VIN = 24V
400
ULTRASONIC MODE
50
PFM MODE
0.01
PWM MODE
450
400
100
ULTRASONIC MODE
50
VIN = 7V
SWITCHING FREQUENCY (kHz)
100
550
0.1
PFM MODE
0
1
0.001
10
0.01
0.1
1
LOAD CURRENT (A)
LOAD CURRENT (A)
LOAD CURRENT (A)
MAX8733A
3.3V OUTPUT SWITCHING
FREQUENCY vs. LOAD CURRENT
MAX8732A
OUT5 VOLTAGE REGULATION
vs. LOAD CURRENT
MAX8732A
OUT3 VOLTAGE REGULATION
vs. LOAD CURRENT
350
300
250
200
150
ULTRASONIC
5.17
5.15
5.13
IDLE MODE
5.11
5.09
50
5.07
PFM MODE
0.01
0.1
LOAD CURRENT (A)
1
10
5.05
0.001
ULTRASONIC
3.40
3.39
3.38
IDLE MODE
3.37
3.36
FORCED-PWM
3.35
FORCED-PWM
ULTRASONIC MODE
3.41
10
MAX8732A/3A/4A toc18
PWM MODE
5.19
OUTPUT VOLTAGE (V)
VIN = 24V
OUTPUT VOLTAGE (V)
MAX8732A/3A/4A toc16
550
MAX8732A/3A/4A toc12
ULTRASONIC MODE
MAX8732A/3A/4A toc14
MAX8732A/3A/4A toc13
SWITCHING FREQUENCY (kHz)
80
MAX8733A
5V OUTPUT SWITCHING
FREQUENCY vs. LOAD CURRENT
150
SWITCHING FREQUENCY (kHz)
120
MAX8733A
3.3V OUTPUT SWITCHING
FREQUENCY vs. LOAD CURRENT
200
0
0.001
160
MAX8733A
5V OUTPUT SWITCHING
FREQUENCY vs. LOAD CURRENT
250
100
200
40
PFM MODE
0.001
10
300
400
ULTRASONIC MODE
240
LOAD CURRENT (A)
PWM MODE
450
50
280
LOAD CURRENT (A)
350
500
75
PWM MODE
LOAD CURRENT (A)
VIN = 7V
0.001
100
0
0.01
450
400
125
25
PFM MODE
0
0.001
150
MAX8732A/3A/4A toc17
80
175
VIN = 24V
320
MAX8732A/3A/4A toc15
240
200
PWM MODE
360
SWITCHING FREQUENCY (kHz)
PWM MODE
VIN = 24V
225
SWITCHING FREQUENCY (kHz)
SWITCHING FREQUENCY (kHz)
280
250
MAX8732A
3.3V OUTPUT SWITCHING
FREQUENCY vs. LOAD CURRENT
MAX8732A/3A/4A toc11
VIN = 7V
320
SWITCHING FREQUENCY (kHz)
360
MAX8732A/3A/4A toc10
3.3V OUTPUT SWITCHING FREQUENCY
vs. LOAD CURRENT (MAX8732A)
3.34
0.01
0.1
LOAD CURRENT (A)
1
10
3.33
0.001
0.01
0.1
1
10
LOAD CURRENT (A)
_______________________________________________________________________________________
9
NBY9843B0NBY9844B0NBY9845B
``````````````````````````````````````````````````````````````````` ࢜ቯᔫᄂቶ)ኚ*
(Circuit of Figure 1 and Figure 2, no load on LDO5, LDO3, OUT3, OUT5, and REF, V+ = 12V, ON3 = ON5 = VCC, SHDN = V+,
RCS = 7mΩ, VILIM_ = 0.5V, TA = +25°C, unless otherwise noted.)
`````````````````````````````````````````````````````````````````````` ࢜ቯᔫᄂቶ)ኚ*
(Circuit of Figure 1 and Figure 2, no load on LDO5, LDO3, OUT3, OUT5, and REF, V+ = 12V, ON3 = ON5 = VCC, SHDN = V+,
RCS = 7mΩ, VILIM_ = 0.5V, TA = +25°C, unless otherwise noted.)
LDO5 REGULATOR OUTPUT VOLTAGE
vs. OUTPUT CURRENT
LDO3 REGULATOR OUTPUT VOLTAGE
vs. OUTPUT CURRENT
4.97
4.96
4.95
2.005
3.346
3.344
3.342
3.340
2.004
2.003
2.002
2.001
2.000
3.338
1.999
3.336
1.998
3.334
1.997
3.332
1.996
3.330
0
10 20 30 40 50 60 70 80 90 100
MAX8732A/3A/4A toc21
3.348
VREF (V)
4.98
REFERENCE VOLTAGE
vs. OUTPUT CURRENT
MAX8732A/3A/4A toc20
4.99
3.350
LDO3 OUTPUT VOLTAGE (V)
MAX8732A/3A/4A toc19
5.00
LDO5 OUTPUT VOLTAGE (V)
NBY9843B0NBY9844B0NBY9845B
᎖܊࢟۾ฎࡼൈĂ
႐ၒ߲ᓍ࢟Ꮞ఼ᒜ
1.995
0
10 20 30 40 50 60 70 80 90 100
-10 0 10 20 30 40 50 60 70 80 90 100
LDO5 OUTPUT CURRENT (mA)
LDO3 OUTPUT CURRENT (mA)
IREF (μA)
REF, LDO3, AND LDO5 POWER-UP
DELAYED-START WAVEFORMS
(ON3 = REF)
DELAYED-START WAVEFORMS
(ON5 = REF)
MAX8732A/3A/4A toc22
10V
LDO5
2V/div
0
MAX8732A/3A/4A toc24
MAX8732A/3A/4A toc23
V+
10V/div
5V
0
LDO3
2V/div
ON5
5V/div
5V
OUT5
2V/div
0
ON3
5V/div
OUT5
2V/div
0
0
REF
1V/div
0
OUT3
2V/div
400μs/div
SOFT-START WAVEFORMS
100μs/div
100μs/div
SHUTDOWN WAVEFORMS
MAX8732A/MAX8734A (TON = VCC)
5V PWM-MODE
LOAD TRANSIENT RESPONSE
MAX8732A/3A/4A toc25
5A
MAX8732A/3A/4A toc26
IL5
5A/div
0
IL3
5A/div
5A
0
3.3V
OUT3
5V/div
0
5V
OUT5
5V/div
0
200μs/div
10
OUT3
2V/div
0
0
0
0
5V
MAX8732A/3A/4A toc27
ON3
5V/div
0
3.3V
0
OUT3
5V/div
5V
OUT5
5V/div
0
5V
SWITCHING
VOUT,
ACCOUPLED
100mV/div
5V
4A
INDUCTOR
CURRENT
2A/div
1A
5V
DL3
5V/div
0
10ms/div
DL5
5V/div
0
20μs/div
______________________________________________________________________________________
᎖܊࢟۾ฎࡼൈĂ
႐ၒ߲ᓍ࢟Ꮞ఼ᒜ
VOUT,
ACCOUPLED
100mV/div
4A
VOUT,
ACCOUPLED
100mV/div
3.3V
4A
INDUCTOR
CURRENT
2A/div
1A
MAX8732A/3A/4A toc30
MAX8732A/3A/4A toc29
MAX8732A/3A/4A toc28
5V
MAX8733A/MAX8734A (TON = GND)
3.3V PWM-MODE
LOAD TRANSIENT RESPONSE
MAX8732A/MAX8734A (TON = VCC)
3.3V PWM-MODE
LOAD TRANSIENT RESPONSE
MAX8733A/MAX8734A (TON = GND)
5V PWM-MODE
LOAD TRANSIENT RESPONSE
INDUCTOR
CURRENT
2A/div
1A
DL5
5V/div
0
DL3
5V/div
0
DL3
5V/div
10μs/div
MAX8733A
3.3V OUTPUT EFFICIENCY
vs. LOAD CURRENT
60
50
ULTRASONIC
MODE
40
30
20
0
0.001
PWM MODE
0.01
0.1
LOAD CURRENT (A)
ON5 = VCC
ON3 = GND
VIN = 7V
VIN = 12V
VIN = 24V
1
MAX8732A/3A/4A toc32
PFM MODE
90
80
EFFICIENCY (%)
90
10
100
MAX8732A/3A/4A toc31
100
EFFICIENCY (%)
1A
0
MAX8733A
5V OUTPUT EFFICIENCY
vs. LOAD CURRENT
70
INDUCTOR
CURRENT
2A/div
20μs/div
10μs/div
80
4A
5V
5V
5V
VOUT,
ACCOUPLED
100mV/div
3.3V
70
PFM MODE
60
50
ULTRASONIC
MODE
40
30
20
10
10
0
0.001
PWM MODE
0.01
0.1
ON5 = VCC
ON3 = VCC
VIN = 7V
VIN = 12V
VIN = 24V
1
10
LOAD CURRENT (A)
______________________________________________________________________________________
11
NBY9843B0NBY9844B0NBY9845B
`````````````````````````````````````````````````````````````````````` ࢜ቯᔫᄂቶ)ኚ*
(Circuit of Figure 1 and Figure 2, no load on LDO5, LDO3, OUT3, OUT5, and REF, V+ = 12V, ON3 = ON5 = VCC, SHDN = V+,
RCS = 7mΩ, VILIM_ = 0.5V, TA = +25°C, unless otherwise noted.)
NBY9843B0NBY9844B0NBY9845B
᎖܊࢟۾ฎࡼൈĂ
႐ၒ߲ᓍ࢟Ꮞ఼ᒜ
``````````````````````````````````````````````````````````````````````````````` ୭ႁී
୭
߂
ถ
—
CS3
4/4W! TNQT࢟ഗଶހၒྜྷăDT4ೌᒗᄴݛᑳഗᏎਜ਼HOEᒄମࡼ࢟ഗଶ࢟ހᔜLjJMJN4ࡼ
࢟ኹࢾሢഗඡሢ)ݬሢഗ࢟വ)JMJN`*ݝॊDžă
—
1
N.C.
2
2
PGOOD
MAX8732A
MAX8733A
MAX8734A
1
12
ᇄೌLjดݝᇄೌă
࢟Ꮞኙၒ߲ăQHPPEဵఎധၒ߲Ljྙਫྀጙവၒ߲ۻணᒏၒ߲࢟߂ܪ܈ኹᒋࢅ21%Lj
QHPPEۻ౯ࢅă
3
3
ON3
4/4W! TNQTဧถၒྜྷăྙਫPO4࣡࢟ኹ᎖TNQTࡼఎ࢟ຳLjᐌ4/4W! TNQTۻဧถǗྙਫPO4
࣡࢟ኹࢅ᎖TNQTࡼਈࣥ࢟ຳLj4/4W! TNQTۻணᒏăྙਫPO4ᎧSFGሤೌLj4/4W! TNQTᏴ
6W! TNQTࡉࡵᆮࢾઁࣅ)ዓߕࣅ*ăPO4࣡࢟ኹདࣅᒗ৺ᑇ༹߹࢟ຳጲሆLjᐌ્ဧ৺ᑇჄ
ࡀ༹ഃă
4
4
ON5
6W! TNQTဧถၒྜྷăྙਫPO6࣡࢟ኹ᎖TNQTࡼఎ࢟ຳLj6W! TNQTۻဧถLjྙਫPO6࣡࢟ኹ
ࢅ᎖TNQTࡼਈࣥ࢟ຳLj6W! TNQTۻணᒏăྙਫPO6ᎧSFGሤೌLj6W! TNQTᏴ4/4W! TNQT
ࡉࡵᆮࢾઁࣅ)ዓߕࣅ*ăPO6࣡࢟ኹདࣅᒗ৺ᑇ༹߹࢟ຳጲሆLjᐌ્ဧ৺ᑇჄࡀ༹ഃă
5
5
ILIM3
4/4W! TNQTሢഗࢯஂăJMJN4ೌࡵWDD ဟLjHOE.MYሢഗඡሢ෦ཱྀᒋᆐ211nWă࣪᎖భࢯෝါLj
ሢഗඡሢᆐJMJN4࣡࢟ኹࡼ2021LjJMJN4࣡࢟ኹपᆍᆐ1/6Wᒗ4Wăᓞધࡵ211nW෦ཱྀᒋࡼ൝ඡ
ሢᏖᆐWDD .! 2WăJMJN4ೌᒗSFGLjభࢾ311nWࡼৼࢾඡሢă
6
6
SHDN
ਈ఼ࣥᒜၒྜྷăྙਫWSHDN ࢅ᎖SHDNၒྜྷሆଢ଼ዘ༤ધ࢟ຳLjୈྜྷਈࣥෝါLjਈࣥෝါ
ሆ࢟Ꮞ࢟ഗଢ଼ᒗ7μBLjᒇࡵWSHDN ᎖SHDNၒྜྷဍዘ༤ધ࢟ຳጲઁLjୈݣถᒮቤࣅă
SHDNೌᒗW,భဣሚᔈࣅࣅăᄰਭ࢟ᔜॊኹSHDNೌᒗW,ถ৫ဣሚభࡼ߈ܠ
་ኹܕჄă
7
7
FB3
4/4W! TNQTनౣၒྜྷăGC4ೌHOEኡᐋৼࢾࡼ4/4Wၒ߲ăGC4ೌᒗPVU4ਜ਼HOEᒄମࡼ
࢟ᔜॊኹLjถ৫ဣሚ3Wᒗ6/6Wࡼభࢯၒ߲ă
8
8
REF
3Wᓰ࢟ኹၒ߲ăᏴSFGਜ਼HOEᒄମጙৈ1/33μG! )ᔢቃᒋ*ࡼ࢟ྏቲവăSFGభᆐᅪݝ
ঌᏲᄋࡉ211μBࡼ࢟ഗăSFGདࣅঌᏲ્ଢ଼ࢅGC`࣡ࡼ࢟ኹਜ਼ၒ߲࢟ኹࡼறࣞLjறࣞଢ଼
ࢅࡼ߈ࣞጞSFGࡼঌᏲࢯᑳᇙތऎࢾă
9
9
FB5
6W! TNQTनౣၒྜྷăGC6ೌHOEኡᐋৼࢾࡼ6Wၒ߲ăGC6ೌᒗPVU6ਜ਼HOEᒄମࡼ
࢟ᔜॊኹLjถ৫ဣሚ3Wᒗ6/6Wࡼభࢯၒ߲ă
10
10
PRO
ਭኹਜ਼་ኹ৺ᑇۣઐဧถ0ணᒏăPROWDD ဟLjணᒏ་ኹĂਭኹۣઐጲૺၒ߲ह࢟ෝါ)EMᏴ
ਈࣥෝါሆᆐࢅ࢟ຳ*ăPROHOEဟLjဧถ་ኹĂਭኹۣઐ)ݬ৺ᑇۣઐ ݝॊ*ጲૺၒ߲ह࢟
ෝါă
11
11
ILIM5
6W! TNQTሢഗࢯஂăJMJN6ೌࡵWDD ဟLjHOE.MYሢഗඡሢ෦ཱྀᒋᆐ211nWă࣪᎖భࢯෝါLj
ሢഗඡሢဵJMJN6࣡࢟ኹࡼ2021LjJMJN6࣡࢟ኹपᆍᆐ1/6Wᒗ4Wăᓞધࡵ211nW෦ཱྀᒋࡼ൝
ඡሢᏖᆐWDD .! 2WăJMJN6ೌᒗSFGLjభࢾ311nWࡼৼࢾඡሢă
12
12
SKIP
ࢅᐅဉෝါ఼ᒜăSKIPHOEဟᔫᏴహሔ)ᄢ൴ߡ*ᔫෝါLjSKIPWDD ဟᔫᏴQXN
ᔫෝါ)ৼࢾຫൈ*ăSKIPSFGኞహᐌᔫᏴިဉෝါ)ᄢ൴ߡLjᔢቃ36lI{*ă
______________________________________________________________________________________
᎖܊࢟۾ฎࡼൈĂ
႐ၒ߲ᓍ࢟Ꮞ఼ᒜ
୭
MAX8732A
MAX8734A
MAX8733A
߂
ถ
13
—
CS5
6W! TNQT࢟ഗଶހၒྜྷăDT6ᎧᄴݛᑳഗᏎਜ਼HOEᒄମࡼ࢟ഗଶ࢟ހᔜሤೌăJMJN6࣡ࡼ
࢟ኹࢾሢഗඡሢ)ݬሢഗ࢟വ)JMJN`*ݝॊDžă
—
13
TON
ຫൈኡᐋၒྜྷăUPOWDD ဟኡᐋ311lI{0411lI{ᔫෝါLjHOEဟኡᐋ511lI{0611lI{ᔫ
ෝါ)ॊܰ࣪።6W04/4W! TNQTࡼఎਈຫൈ*ă
14
14
BST5
6W! TNQTࡼᔈ࢟ྏೌ࣡ăږᑍ࢜ቯ።࢟വ)ᅄ2ਜ਼ᅄ3*LjCTU6ೌࡵᅪྏ࢟ݝਜ਼औă
ݬ NPTGFUᐜདࣅ)EI`ĂEM`*ݝॊă
15
15
LX5
16
16
DH5
17
17
VCC
6W! TNQTࡼ࢟ঢೌ࣡ăMY6ဵܟᐜདࣅEI6ࡼด࢟࣡ࢅݝᏎਜăMY6ဵ6W! TNQTࡼ
࢟ഗଶހၒྜྷ)ஞNBY9845B*ă
6W! TNQTࡼܟNPTGFUᐜདࣅၒ߲ăEI6ࡼڼ७ᆐ࠭MY6ࡵCTU6ă
QXNਖ਼ࡼෝผ࢟Ꮞ࢟ኹၒྜྷăWDD ᄰਭጙৈ61Ωࡼࠈೊ࢟ᔜೌᒗᇹᄻ࢟ኹᏎăᄰਭጙᒑ2μG
ჿࠣ࢟ྏവᒗHOEă
6Wሣቶᆮኹၒ߲ăMEP6ဵᅪݝNPTGFUࡼᐜདࣅ࢟ᏎăMEP6ถᆐNPTGFUᐜདࣅਜ਼
ᅪݝঌᏲᄋ211nBࡼᔐ࢟ഗăดݝঌᏲࡼࡍቃན᎖ኡᐋࡼNPTGFUਜ਼ఎਈຫൈ)ݬᓰ
ਜ਼ሣቶᆮኹ)SFGĂMEP6ਜ਼MEP4*ݝॊ*ăྙਫPVU6࣡࢟ኹࡍ᎖MEP6ᔈఎਈඡሢLjกඐ
MEP6ᆮኹਈࣥLj݀༦MEP6ᄰਭጙৈࡴᄰ࢟ᔜ2/5ΩࡼఎਈᎧPVU6ೌăݧጙৈ5/8μG
)ᔢቃᒋ*ࡼ࢟ྏവMEP6ăঌᏲ࢟ഗඛᐐଝ6nBLj࢟ྏࡼྏᐐࡍ2μGă
18
18
LDO5
19
19
DL5
6W! TNQTᄴݛᑳഗᐜདࣅၒ߲ăEM6ࡼڼ७ᆐ࠭HOEࡵMEP6ă
20
20
V+
࢟Ꮞ࢟ኹၒྜྷăW,ᆐMEP60MEP4ሣቶᆮኹ࢟LjጐᆐRvjdl.QXNࡴᄰဟମĂᆮზ࢟വ࢟ă
W,࢟ߔၒྜྷLj݀ጙᒑ1/2μG࢟ྏቲവă
21
21
OUT5
6W! TNQTၒ߲࢟ኹଶހၒྜྷăೌᒗ6W! TNQTၒ߲ăPVU6ဵRvjdl.QXNࡴᄰဟମLjᆮზ࢟വ
ࡼၒྜྷăᏴৼࢾ࢟ᏎෝါሆLjকၒ߲થᔫᆐ6WࡼनౣၒྜྷăྙਫPVU6࣡࢟ኹࡍ᎖MEP6ࡼᔈ
ఎਈඡሢᒋLjMEP6ሣቶᆮኹਈࣥLjMEP6ᄰਭጙৈ2/5Ωࡴᄰ࢟ᔜࡼఎਈೌᒗPVU6ă
22
22
OUT3
4/4W! TNQTၒ߲࢟ኹଶހၒྜྷăೌᒗ4/4W! TNQTၒ߲ăPVU4ဵRvjdl.QXNࡴᄰဟମĂᆮზ
࢟വࡼၒྜྷăᏴৼࢾ࢟ᏎෝါሆLjকၒ߲થᔫᆐ4WࡼनౣၒྜྷăྙਫPVU4࣡࢟ኹࡍ᎖MEP4ࡼ
ᔈఎਈඡሢᒋLjMEP4ሣቶᆮኹਈࣥLjMEP4ᄰਭጙৈࡴᄰ࢟ᔜ2/6ΩࡼఎਈೌᒗPVU4ă
23
24
23
24
GND
DL3
ෝผਜ਼ൈă
4/4W! TNQTᄴݛᑳഗᐜདࣅၒ߲ăEM4ࡼڼ७࠭HOEࡵMEP6ă
4/4Wሣቶᆮኹၒ߲ăSFGࡉࡵᆮࢾઁLjMEP4ఎဪ࢟ăMEP4భᆐᅪݝঌᏲᄋ211nBࡼ
ᔐ࢟ഗăྙਫPVU4࣡࢟ኹ᎖MEP4࣡ࡼᔈఎਈඡሢ࢟ኹLjMEP4ᆮኹਈࣥLjMEP4ᄰਭ
ጙৈࡴᄰ࢟ᔜ2/6ΩࡼఎਈೌᒗPVU4ăݧᔢቃᒋᆐ5/8μGࡼ࢟ྏവMEP4ăঌᏲ࢟ഗඛ
ᐐଝ6nBLjক࢟ྏࡼྏᐐࡍ2μGă
25
25
LDO3
26
26
DH3
4/4W! TNQTࡼܟNPTGFUᐜདࣅၒ߲ăEI4ࡼڼ७࠭MY4ࡵCTU4ă
27
27
LX3
4/4W! TNQTࡼ࢟ঢೌ࣡ăMY4ဵ4/4W! TNQTࡼ࢟ഗଶހၒྜྷ)ஞNBY9845B*ă
28
28
BST3
4/4W! TNQTࡼᔈ࢟ྏೌ࣡ăږᑍ࢜ቯ።࢟വ)ᅄ2ਜ਼ᅄ3*LjCTU4ೌࡵᅪྏ࢟ݝਜ਼औ
ăݬ NPTGFUᐜདࣅ)EI`ĂEM`*ݝॊă
______________________________________________________________________________________
13
NBY9843B0NBY9844B0NBY9845B
```````````````````````````````````````````````````````````````````````` ୭ႁී)ኚ*
NBY9843B0NBY9844B0NBY9845B
᎖܊࢟۾ฎࡼൈĂ
႐ၒ߲ᓍ࢟Ꮞ఼ᒜ
````````````````````````````࢜ቯ።࢟വ
ܭ2/! Ꮔୈ።
࢜ቯ።࢟വ)ᅄ 2 ਜ਼ 3*భ৩܊࢟۾ฎᓍ࢟Ꮞ࢟
വLjᆐᄋ6W06Bਜ਼4/4W06B࢟Ꮞăၒྜྷ࢟ኹपᆍᆐ8W
ᒗ35WăᏄୈ።ྙܭ2Ⴥာă
````````````````````````````````ሮᇼႁී
NBY9843B0NBY9844B0NBY9845BၷcvdlĂCjDNPTఎਈ
࢟Ꮞ)TNQT*఼ᒜభޘည܊࢟۾ฎჅኊࡼ൝࢟Ꮞă
NBY9843B0NBY9844B0NBY9845Bᓍገᑣ࣪࢟ߔ࢟።
ଐLj൸ᔗൈਜ਼ࢅஸზ࢟Ꮞ࢟ഗገཇăNBY9843B
ۻᎁછ᎖6W0311lI{ TNQTਜ਼4/4W0411lI{ TNQTLjᎌᔢ
ൈăNBY9844Bᐌᑣ༵࣪Ăۡಢ።ቲ೫ᎁછLj
MANUFACTURER
PHONE
FAX
Central Semiconductor
516-435-1110
516-435-1824
Dale-Vishay
402-564-3131
402-563-6418
Fairchild
408-721-2181
408-721-1635
International Rectifier
310-322-3331
310-322-3332
NIEC (Nihon)
805-843-7500
847-843-2798
Sanyo
619-661-6835
619-661-1055
Sprague
603-224-1961
603-224-1430
Sumida
847-956-0666
847-956-0702
Taiyo Yuden
408-573-4150
408-573-4159
TDK
847-390-4461
847-390-4405
VIN 7V TO 24V
5V ALWAYS ON
1μF
4.7μF
50Ω
VCC
LDO5
ILIM3
1μF
VCC
0.1μF
10μF
BST5
10Ω
DH5
0.1μF
L5
N3
FDS6612A
DH3
MAX8732A
MAX8733A
0.1μF
LX5
L3
LX3
C5
3.3V
C3
D3
EP10QY03
N2
IRF7811AV
DL5
DL3
CS5
CS3
OUT3
OUT5
RCS5
20mΩ
FB5
N4
IRF7811AV
VCC
FB3
100kΩ
ON
OFF
SHDN
VCC
ON5
REF
ON3
D2
EP10QY03
RCS3
20mΩ
PGOOD
SKIP
FREQUENCY-DEPENDENT COMPONENTS
MAX8732A
MAX8733A
5V/3.3V SMPS
SWITCHING FREQUENCY
200kHz/300kHz
400kHz/500kHz
L3
4.7μH
3.0μH
GND
REF
PRO
LDO3
1MΩ
3.3V ALWAYS ON
L5
7.6μH
5.6μH
C3
470μF
220μF
C5
330μF
150μF
0.22μF
4.7μF
ᅄ2/! NBY9843B0NBY9844B࢜ቯ።࢟വ
14
10μF
BST3
10Ω
5V
10μF
CMPSH-3A
1/2
D1
N1
FDS6612A
1/2
D1
ILIM5
V+
______________________________________________________________________________________
᎖܊࢟۾ฎࡼൈĂ
႐ၒ߲ᓍ࢟Ꮞ఼ᒜ
NBY9843B0NBY9844B0NBY9845B
VIN 7V TO 24V
5V ALWAYS ON
1μF
50Ω
4.7μF
VCC
LDO5
ILIM3
1μF
VCC
1/2
D1
ILIM5
V+
0.1μF
10μF
BST5
10Ω
N1
FDS6612A
DH5
N3
FDS6612A
DH3
MAX8734A
0.1μF
0.1μF
L5
LX5
L3
LX3
470pF*
C5
10μF
BST3
10Ω
5V
10μF
CMPSH-3A
1/2
D1
SEE
TABLE
TON
D3
EP10QY03
N2
IRF7811AV
DL5
DL3
OUT5
OUT3
FB5
470pF*
N4
IRF7811AV
3.3V
C3
D2
EP10QY03
VCC
FB3
100kΩ
ON
SHDN
OFF
VCC
ON5
REF
ON3
PGOOD
SKIP
GND
REF
PRO
LDO3
1MΩ
3.3V ALWAYS ON
0.22μF
*OPTIONAL CAPACITANCE BETWEEN
LX AND PGND (CLOSE TO THE IC) ONLY
REQUIRED FOR ULTRASONIC MODE
4.7μF
FREQUENCY-DEPENDENT COMPONENTS
TON = VCC
TON = GND
200kHz/300kHz
400kHz/500kHz
L3
4.7μH
3.0μH
L5
7.6μH
5.6μH
C3
470μF
220μF
C5
330μF
150μF
5V/3.3V SMPS
SWITCHING FREQUENCY
ᅄ3/! NBY9845B࢜ቯ።࢟വᅄ
______________________________________________________________________________________
15
NBY9843B0NBY9844B0NBY9845B
᎖܊࢟۾ฎࡼൈĂ
႐ၒ߲ᓍ࢟Ꮞ఼ᒜ
ᎌ6W0511lI{ TNQTਜ਼4/4W0611lI{ TNQTăNBY9845Bభᄰ
ਭ୭ኡᐋఎਈຫൈLjᏤ 6W ਜ਼ 4/4W TNQT ॊܰᔫᏴ
311lI{0411lI{ਜ਼511lI{0611lI{ఎਈຫൈሆă
ጙৈᑳഗጲૺጙৈMDၒ߲݆ᔝ߅ăၒ߲࢟ኹဵఎ
ਈஂ࢛ࡼຳBD࢟ኹLjᄰਭখܤNPTGFUఎਈࡼᐴహ܈
࣪ᑚৈ࢟ኹቲࢯஂăܟoࡸNPTGFUࡼᐜདࣅቧ
ܘኍ᎖࢟ߔ࢟ኹLjᑚဵᎅCTU`࣡ࡼ211oGॳࣅ࢟ྏ৩
߅ࡼᔈ࢟വᄋࡼă
ᄰਭᔈࣅ༤ધࡵహሔᔫෝါభᄋ༵ᏲൈLjᑚᒬຫ
ൈభࡼܤᄢ൴ߡෝါଢ଼ࢅ೫ఎਈႼਜ਼ᐜߠ࢟Ⴜă
ඛৈ cvdl ᓞધࡼൈఎਈ࢟വᎅೝৈ o ࡸ NPTGFUĂ
V+
PGOOD
MAX8732A
MAX8733A
MAX8734A
PGOOD3
PGOOD5
TON
(MAX8734 ONLY)
BST3
BST5
DH3
DH5
LX3
3.3V
SMPS PWM
CONTROLLER
LDO5
LX5
5V
SMPS PWM
CONTROLLER
LDO5
DL5
DL3
CS3
(MAX8732A/
MAX8733A)
CS5
(MAX8732A/
MAX8733A)
ILIM5
ILIM3
FB3
FB5
OUT3
OUT5
EN3
LDO3
4.56V
2.91V
EN5
5V
LINEAR
REG
3V
LINEAR
REG
LDO5
VCC
ON3
ON5
POWER-ON SEQUENCE/
CLEAR FAULT LATCH
THERMAL
SHUTDOWN
SHDN
2V
REFERENCE
PRO
REF
GND
ᅄ4/! ሮᇼࡼถౖᅄ
16
______________________________________________________________________________________
᎖܊࢟۾ฎࡼൈĂ
႐ၒ߲ᓍ࢟Ꮞ఼ᒜ
ᒜᓍQXNࡼ࢟ၿኔLj݀ପ၁ၒ߲ࡼ་ኹ৺ᑇăNBY9843B0
NBY9844B0NBY9845Bથ۞౪6Wਜ਼4/4Wሣቶᆮኹăມ
ᒙ࢟വ۞౪6W! )MEP6*ሣቶᆮኹĂ3Wறමᓰጲૺᔈࣅ
ᔈ༤ધ࢟വă
V+
OUT
TON (MAX8734A)
ON-TIME
COMPUTE
tOFF
Q
TRIG
ONE SHOT
tON
TRIG
Q
R
TO DH_ DRIVER
ONE SHOT
Q
REF
S
ERROR
AMPLIFIER
ILIM_
CURRENT
LIMIT
Σ
TO DL_ DRIVER
CS_ (MAX8732A/8733A)
LX_ (MAX8734A)
ZERO
CROSSING
S
Q
R
SKIP
OUT_
PGOOD
0.9 x VREF
FB_
OV_FAULT
UV_FAULT
FAULT
LATCH
1.1 x VREF
0.15V
PRO
20ms
BLANKING
0.7 x VREF
ᅄ5/! QXN఼ᒜ)ᒑဵᒦጙ*ݾ
______________________________________________________________________________________
17
NBY9843B0NBY9844B0NBY9845B
ඛവQXN఼ᒜᎅၷෝါनౣᆀਜ਼ࣶവআĂࣶၒ
ྜྷQXN୷܈Ăܟਜ਼ࢅܟᐜདࣅጲૺ൝࢟വᔝ
߅ăNBY9843B0NBY9844B0NBY9845Bᎌ৺ᑇۣઐ࢟വLj
భପ၁ᓍQXNၒ߲ࡼ་ኹਜ਼ਭኹ৺ᑇă࢟ኔෝ఼్
NBY9843B0NBY9844B0NBY9845B
᎖܊࢟۾ฎࡼൈĂ
႐ၒ߲ᓍ࢟Ꮞ఼ᒜ
ᑚቋดݝෝ్ဵݙᎅ࢟ߔᒇ࢟Ljऎဵᎅ 6W! )MEP6*
ሣቶᆮኹሌ࢟ߔ࢟ኹଢ଼ࢅLjᏳᆐด࢟ݝവਜ਼ᐜད
ࣅ࢟ăᄴݛఎਈᐜདࣅᎅMEP6ᒇ࢟Ljऎ
ܟఎਈᐜདࣅဵᄰਭᅪݝऔ.࢟ྏᔈ࢟വLjᎅ
MEP6ମ࢟ăࡩPVU6࢟ኹࡍ᎖5/67WဟLjᔈࣅᔈ࢟
വਈࣥ6WሣቶᆮኹLj݀ᎅPVU6ᆐୈ࢟ă
ࡒၒྜྷ༄ౣLjᔈᎅᏥቲࡼ
ੱࡴᄰဟମQXN఼ᒜ
Rvjdl.QXN఼ᒜଦ৩ဵጙᒬࡒ࢟ኹ༄ౣࡼᆗৼࢾຫൈĂੱ
ࡴᄰဟମĂ࢟ഗෝါ఼ᒜăᑚᒬ఼ᒜଦ৩ಽၒ߲࢟
ኹᆬ݆ᔫᆐQXNቓ݆ቧLjፐࠥၒ߲݆࢟ྏࡼFTSᔫ
ಢ႒᎖࢟ഗनౣ࢟ᔜăܟఎਈࡼࡴᄰဟମஞᎅጙৈ
ᆮზ࢟വࢾLj൴Ꭷၒྜྷ࢟ኹ߅न܈ऎᎧၒ߲
࢟ኹ߅ᑵ܈ăጙৈᆮზ࢟വభᒙ411otࡼᔢቃਈࣥ
ဟମ)࢜ቯᒋ*ăࡴᄰဟମᆮზ࢟വࡼ߿खᄟୈᆐǖᇙތ
୷܈ᆐࢅLjᄴݛᑳഗ࢟ഗࢅ᎖ሢഗඡሢLj݀༦ᔢቃ
ਈࣥဟମጯਭă
ࡴᄰဟମᆮზ)uPO*
QXN ఼ᒜࡼਖ਼ቦݝॊဵጙৈᆮზ࢟വLjᒙ
ܟఎਈࡼࡴᄰဟମăᑚৈႥĂࢅ࣌ࣅĂభࢯஂࡼᆮზ
࢟വถ৫ো࢟ߔਜ਼ၒ߲࢟ኹࡼܤછখࡴܤᄰဟମăܟ
ఎਈࡼࡴᄰဟମᎧ࢟ߔ࢟ኹ)భᄰਭW,ၒྜྷ߅*ࡻހन܈Lj
ऎᎧၒ߲࢟ኹ߅ᑵ܈ăᎌৼࢾຫൈࡼဟᒩखညLj
ࡣᑚᒬႯजభޘညதઃੱࢾࡼఎਈຫൈăੱࢾఎਈຫൈࡼ
ੑࠀᏴ᎖భᄰਭኡᐋຫൈܜఎැঢຫࣤǖ
t ON =
K(VOUT + 0.075V )
V+
த႒ࡼLፐᔇݬܭ3ăޟၫ1/186Wဵ࣪ᄴݛᑳഗఎਈኹ
ଢ଼ࡼத႒ৰଐăఎਈຫൈ્ႲঌᏲ࢟ഗࡼᐐଝऎᐐଝLj
ᑚဵፐᆐႲᓹᄴݛᑳഗೝ࣡ࡼኹଢ଼ᐐࡍLj࢟ঢ࢟ഗጲ
ৎࡼႥൈሆଢ଼ă
ࡴᄰဟମஞཀྵࢾ೫ጙৈࡍᒘࡼఎਈຫൈăFmfdusjdbm
Dibsbdufsjtujdt ৃܭᒦჅۣᑺࡼࡴᄰဟମથ၊ᅪݝܟ
ൈNPTGFUఎਈዓဟࡼ፬ሰăᄴဟLjႌཌဟମ።ᐐଝ೫
ᎌࡴᄰဟମLjଢ଼ࢅ೫ఎਈຫൈăᒑᎌᏴ QXN ෝါሆ
)SKIP = WDD*LjᏴၒ߲࢟ኹࣅზᓞܤ໐ମLjࡩ࢟ঢ࢟ഗᏴ
༵ᏲঌࡼঌᏲ࢟ഗሆखညनᓞဟLj્ݣखညႌཌဟମ
።ă࢟ঢ࢟ഗनሶဟLj࢟ঢࡼঢည࢟ࣅဴ)FNG*ဧ MY
܈ᑵ༽ޟౚሆৎᐁဍLjဧࡴᄰဟମዓޠ೫ጙৈEI
ဍዘႌཌဟମă
࣪᎖ஏࠅࡴ࢛ጲࡼঌᏲLjဣଔఎਈຫൈᆐǖ
f=
VOUT + VDROP1
t ON ( V + + VDROP2 )
ᒦ WESPQ2 ဵ࢟ঢह࢟ᄰവࡼညኹଢ଼ᒄਜ਼Lj۞౪ᄴ
ݛᑳഗĂ࢟ঢਜ਼፝ᒜۇᒦࡼ࢟ᔜǗ W ESPQ3 ᐌဵߠ࢟ᄰ
വᔐࡼညኹଢ଼Lj۞౪ܟఎਈĂ࢟ঢጲૺ፝ᒜۇᒦࡼ
࢟ᔜǗuPO ဵNBY9843B0NBY9844B0NBY9845BଐႯ߲ࡼ
ࡴᄰဟମă
ᄢ൴ߡᔈࣅ༤ધ)హሔෝါ*
Ᏼహሔෝါሆ)SKIP = HOE*Lj༵Ᏺဟᔈࣅ༤ધᒗ QGN
ෝါăᑚᒬ༤ધ၊఼᎖ጙৈ୷܈Ljক୷܈Ᏼ࢟ঢ࢟
ഗਭഃဟᒫᒏࢅܟఎਈࡼࡴᄰဟମăᑚᒬऱါဧᄢ൴ߡ
ࡼ QGN ਜ਼ऻᄢ൴ߡࡼ QXN ᔫෝါᒄମࡼॊஏ࢛ᑵੑ
ܭ3/! த႒Lፐᔇᇙތ
SMPS
MAX8732A/MAX8734A (tON = VCC), 5V
MAX8732A/MAX8734A (tON = VCC), 3.3V
MAX8733A/MAX8734A (tON = GND), 5V
MAX8733A/MAX8734A (tON = GND), 3.3V
18
SWITCHING FREQUENCY
(kHz)
200
300
400
500
K-FACTOR (μs)
5.0
3.3
2.5
2.0
APPROXIMATE KFACTOR ERROR (%)
±10
±10
±10
±10
______________________________________________________________________________________
᎖܊࢟۾ฎࡼൈĂ
႐ၒ߲ᓍ࢟Ꮞ఼ᒜ
ILOAD(SKIP) =
K × VOUT _ ⎛ V + − VOUT _ ⎞
⎜
⎟
2×L
V+
⎝
⎠
ᒦ L ဵࡴᄰဟମ܈ಿፐᔇ)ݬ ࡴᄰဟମᆮზ)u PO* *ă
QGN0QXN༤ધ࢛ࡼঌᏲ࢟ഗJMPBE)TLJQ*ࢀ᎖ख़.ख़ᆬ݆࢟
ഗࡼጙۍLjဵ࢟ঢࡼၫ)ᅄ6*ăಿྙLjᏴNBY9843B
࢜ቯ።࢟വ ᒦLjWPVU3! = 6WLjW,! = 23WLjM! = 8/7μILj
L!= 6μtဟLjሶᄢ൴ߡᔫෝါࡼᓞધखညᏴJMPBE = 1/:7B
ᑗᏖᆐ൸Ᏺ࢟ഗࡼ206ăྙਫݧૄᓞ)ྟۥਜ਼*࢟ঢLj༤
ધ࢛खညᏴৎࢅࡼᒋă
ࡩঌᏲି༵ઁྜྷᄢ൴ߡᔫෝါဟLjఎਈ݆ተ્߲ሚ
୷ࡍᐅဉਜ਼ݙᄴݛሚሷLjࡣᑚဵᑵࡼޟᔫᓨზLjፐᆐ
Ᏼ༵Ᏺሆᎌൈăᄰਭখ࢟ܤঢᒋLjభᏴ QGN ᐅ
ဉᎧ༵Ᏺൈᒄମནࡻ୷ੑࡼຳੰăᄰޟLjࢅ࢟ঢᒋሆൈ.ঌᏲཎሣࡼܤછී୷܈መǗऎ࢟ঢᒋᐌభޘည୷
ࡼ൸ঌᏲൈ)ଣࢾሣམ࢟ᔜۣߒৼࢾ*Ljጲૺ୷ࢅࡼၒ
߲࢟ኹᆬ݆ăဧᒋ࢟ঢࡼࡔଥဵৎࡍࡼᇕಯߛࡁૺ
ࡼތܤঌᏲၾზሰ።)ᎄဵᏴࢅၒྜྷ࢟ኹဟ*ă
ᒇഗၒ߲றࣞᒎܪᎧᇙ୷܈ތࡼ߿ख࢟ຳᎌਈăࡩ࢟
ঢࠀ᎖ೌኚࠅࡴෝါဟLjၒ߲࢟ኹࡼᒇഗᆮኹᒋ߿܈ख
࢟ຳ߲61%ࡼᆬ݆࢟ኹăऎᏴऻೌኚࠅࡴෝါሆ)SKIP
= HOELj༵Ᏺ*Ljᎅ᎖ࡀᏴቓൈޡݗLjၒ߲࢟ኹࡼᒇഗᆮ
ኹᒋ߿܈ख࢟ຳࡍᏖ2/6%ă
Δi
=
V+ - VOUT
L
-IPEAK
INDUCTOR CURRENT
Δt
༓ᒜQXNෝါ
ࢅᐅဉĂ༓ᒜQXN! )SKIP = WDD*ෝါሆLj఼ᒜࢅܟఎਈ
ࡴᄰဟମࡼਭഃ୷܈ۻணᒏăᑚဧࡻࢅܟᐜདࣅ݆
ተᎧܟᐜདࣅ݆ተઑݗăQXN ણവۣߒᐴహ܈ᆐ
W PVU 0W,Ljᑚ્ࡴᒘ࢟ঢ࢟ഗᏴ༵Ᏺဟनᓞă༓ᒜ
QXNෝါࡼᎁ࢛ဵۣߒఎਈຫൈሤ࣪ੱࢾLjࡣጐገঈ߲
ጙࢾࡼࡔଥǖహᏲဟࡼ࢟ߔ࢟ഗ્ࡉ21nBᒗ61nBLjᎧ
ᄏࡼఎਈຫൈૺᅪݝNPTGFUᎌਈă
༓ᒜQXNෝါऻޟᎌಽ᎖ሿ߹ፒຫᐅဉĂখ࿖ঌᏲၾზ
ሰ።ጲૺᄋᇢ၃࢟ഗࡼถೆ)ጲܣၒ߲࢟ኹࡼࣅზࢯ
ஂ*LjᏴ᎖न૮ܤኹẮ࢟ঢࡼࣶၒ߲።ᒦLjથ
খ࿖೫ୣஂࢯބቶถă
ᐐ༓ቯިဉෝါ
)36lI{ )ᔢቃ*ᄢ൴ߡ*
SKIPኞహSKIPSFGLjࣅᄂᎌࡼĂᔢቃఎਈ
ຫൈᆐ36lI{ࡼᄢ൴ߡෝါăᑚᒬިဉᄢ൴ߡෝါሿ߹೫
ፒຫࢯᒜLj࠭ऎܜ఼ᒜᏴ༵Ᏺ༽ౚሆᔈࣅᓞᆐᄢ൴
ߡෝါဟ߲ሚፒຫᐅဉăᏴިဉෝါሆLjࡩঌᏲࡉࡵᎧ
ᑵޟᄢ൴ߡෝါሤᄴࡼஏࠅࡴ࢛)JMPBE)TLJQ**ဟLjক఼
ᒜభᔈࣅᓞધᆐৼࢾຫൈQXNᔫෝါă
ྙਫᏴߒኚ39μtࡼဟମดLj఼ᒜᎌଶࡵހఎਈࣅᔫLj
્ޘညިဉ൴ߡăጙࡡ߿खLjިဉ఼ᒜ౯EMLjࡴᄰ
ࢅܟNPTGFULjޘညनሶ࢟ঢ࢟ഗăࡩ࢟ঢ࢟ഗࡉࡵनሶ
ިဉ࢟ഗඡሢဟLj఼ᒜਈࣥࢅܟNPTGFU! )EMۻ౯ࢅ*Lj
݀߿खੱࡴᄰဟମ߿ख)EIۻ౯*ăࡴᄰဟମஉၦઁLj
఼ᒜᒮቤࡌఎࢅܟNPTGFULjᒇࡵ఼ᒜଶ࢟ࡵހঢ࢟
ഗࢰൢᒗਭഃଶހඡሢጲሆăሌࣅEM൴ߡᎧሌࣅEI
൴ߡሤ܈Lj્ࡍࡍଢ଼ࢅၒ߲࢟ኹᆬ݆ࡼख़ᒋăިဉ൴ߡ
ఎဪဟࡼၒ߲࢟ኹࢾ೫नሶިဉ࢟ഗࡼଶހඡሢLjభ
োሆါቲଐႯǖ
VISONIC = IL RON = ( VREF − VFB ) × 0.58
ILOAD = IPEAK / 2
ᒦWGC > WSFGLjSPO ဵᄴݛᑳഗࡼࡴᄰ࢟ᔜ)NBY9845B*
࢟ഗଶ࢟ހᔜࡼᔜᒋ)NBY9843B0NBY9844B*ă
0 ON-TIME
TIME
ᅄ6/! ᄢ൴ߡ0ೌݙኚෝါᓞધ࢛
______________________________________________________________________________________
19
NBY9843B0NBY9844B0NBY9845B
Ꭷೌኚਜ਼ऻೌኚ࢟ঢ࢟ഗᔫෝါᒄମࡼॊஏ࢛)ጐ߂ᆐ
ஏࠅࡴ࢛*ሤᒮă
ᓰਜ਼ሣቶᆮኹ
)SFGĂMEP6ਜ਼MEP4*
ᏴᑳৈᆨࣞपᆍดLj3Wᓰ࢟ኹ)SFG*ࡼறࣞభࡉ ±2%Lj
ፐࠥ SFG ऻޟးᔫᇹᄻࡼறම࢟ኹᓰăဧጙৈ
1/33μG! )ᔢቃ*ࡼ࢟ྏSFGവᒗHOEăSFGభᆐᅪݝঌ
Ᏺᄋࡉ211μBࡼ࢟ഗăऎLjྙਫᓍၒ߲࢟ኹਜ਼SFG
࣒ኊገࡼறࣞLjገܜᏴSFGଝᏲăᎅ᎖ᓰᏎ
ࡼঌᏲࢯᑳᇙތLj SFG ଝᏲ્ࡴᒘ MEP6ĂMEP4Ă
PVU6ਜ਼PVU4ၒ߲࢟ኹ༵ᆈሆଢ଼ă
ೝৈดݝᆮኹޘည6W!)MEP6*ਜ਼4/4W!)MEP4*ၒ߲ăMEP6
ᆐᅪݝNPTGFUࡼᐜདࣅ࢟LjᄴဟጐᆐQXN఼ᒜ
Ă൝ᏄĂᓰ࢟വጲૺୈดࡼݝෝ్࢟ă
MEP6 ᆮኹభᆐดݝਜ਼ᅪݝঌᏲᄋ 211nB ࡼᔐ࢟ഗLj
ᒦ۞౪NPTGFUᐜདࣅ࢟ഗLjᄰޟ᎖21nBᒗ61nB
ᒄମLjᎧఎਈຫൈਜ਼Ⴥኡࡼᅪ ݝNPTGFU ᎌਈăࡩᓰ
)SFG*ࡉࡵᆮࢾઁLjMEP4 ࢟LjభᆐᅪݝঌᏲᄋࡉ
211nBࡼ࢟ഗăMEP6ਜ਼MEP4።ᄰਭጙᒑᔢቃ5/8μGࡼ
࢟ྏവLjดݝਜ਼ᅪݝঌᏲ࢟ഗඛᐐଝ 6nBLjক࢟ྏࡼ
ྏ።ᐐࡍ2μGă
ࡩ6Wᓍၒ߲࢟ኹ᎖MEP6ᔈ༤ધඡሢဟLjดݝ2/5Ωࡼ
qࡸNPTGFUఎਈPVU6ೌᒗMEP6LjᄴဟਈࣥMEP6
ሣቶᆮኹăᄴዹLjࡩ4/4Wᓍၒ߲࢟ኹ᎖MEP4ᔈ༤
ધඡሢဟLjดݝ2/6Ω ࡼqࡸNPTGFUఎਈڳPVU4ೌ
ࡵ MEP4Ljᄴဟਈࣥ MEP4 ሣቶᆮኹăᑚዹဧୈ
ᔈᔫLjᎅTNQTၒ߲ᆐด࢟ݝവਜ਼ᅪݝঌᏲ࢟Ljऎ
ဵݙᎅ࢟ߔᄰਭሣቶᆮኹࢯஂઁࡼၒ߲࢟ăᎅ᎖ဵ
ᄰਭጙৈൈᆐ:1%ࡼఎਈࢯஂᄋ࢟ᏎLjऎဵݙᄰਭ
ൈࢅࡻࣶࡼሣቶᆮኹ࢟LjፐࠥLjᔈᔫభଢ଼ࢅ
ᎅ᎖ᐜ࢟ਜ਼ஸზႼჅࡼă
ሢഗ࢟വ)JMJN`*
ሢഗ࢟വݧĐ৸đ࢟ഗଶހजăNBY9845Bဧᄴݛᑳഗ
ࡴᄰ࢟ᔜᔫᆐ࢟ഗଶހᏄୈLjऎNBY9843B0NBY9844B
ᐌݧᎧᄴݛᑳഗᏎࠈೊࡼॊೂ࢟ᔜᔫᆐ࢟ഗଶހᏄ
ୈăྙਫDT`! )NBY9843B0NBY9844B*0MY`! )NBY9845B*
࣡ࡼଶഗቧ७ᒋࡍ᎖ሢഗඡሢLjᐌQXNݙࣅቤࡼᒲ
໐)ᅄ 8*ăဣଔࡼख़ᒋ࢟ഗገ܈ሢഗඡሢ߲ጙৈ࢟ঢᆬ
݆࢟ഗࡼᒋăፐࠥLjဣଔࡼሢഗᄂቶਜ਼ᔢࡍࡒᏲถೆᎧ
ሢഗඡሢĂ࢟ঢᒋጲૺၒྜྷਜ਼ၒ߲࢟ኹᎌਈă
࣪᎖NBY9843B0NBY9844BLjDT`ೌࡵᄴݛᑳഗᏎ
ਜ਼࢟ഗଶ࢟ހᔜࡼೌ࢛Ljক࢟ᔜࡼጙ࣡ೌ HOEă
ሢഗඡሢᆐ 211nW ဟLjறࣞᏖᆐ ±8%ă࢟ഗଶހඡሢᏗ
ࢅLjறࣞጐᏗࢅă࢟ഗଶ࢟ހᔜᒑᏴᄴݛᑳഗࡴᄰဟ
ሿൈă
ᆐ೫ጙݛଢ଼ࢅLjNBY9845Bಽᄴݛᑳഗࡼࡴᄰ
࢟ᔜᔫᆐ࢟ഗଶހᏄୈăSET)PO* ።ནNPTGFUၫᓾ೯
ᒦᔢ༽ތౚሆࡼᔢࡍᒋLjఠࡵSET)PO*્Ⴒᆨࣞဍऎ
ᐐࡍLjથገഔᎌጙࢾࡼLjᄰࡼޟளዩဵᆨࣞඛဍ
2°DLj࢟ᔜᒋገᐐଝ1/6%ăሢഗᒋ્Ⴒᄴݛᑳഗࡼࡴ
ᄰ࢟ᔜܤછăᑚᒬऱါࡼੑࠀဵభణĂᇄႼࡼਭഗଶހă
ࡩᎧ་ኹۣઐ࢟വဧဟLjকሢഗऱါଂઃᏴჅᎌ
ણஹᒦ࣒ᎌă
40μs (MAX)
INDUCTOR
CURRENT
-IPEAK
ILOAD
ZERO-CROSSING
DETECTION
0
INDUCTOR CURRENT
NBY9843B0NBY9844B0NBY9845B
᎖܊࢟۾ฎࡼൈĂ
႐ၒ߲ᓍ࢟Ꮞ఼ᒜ
ILIMIT
ISONIC
ON-TIME (tON)
0
TIME
ᅄ8/Đ৸đሢഗඡሢ࢛
ᅄ7/! ިဉෝါ࢟ഗ݆ተ
20
______________________________________________________________________________________
᎖܊࢟۾ฎࡼൈĂ
႐ၒ߲ᓍ࢟Ꮞ఼ᒜ
ሢഗඡሢᄰਭJMJN`࣡ᅪࡼॊኹࢯஂăሢഗඡሢࢯ
ஂपᆍᆐ61nWᒗ411nWăᏴభࢯෝါሆLjሢഗඡሢ࢟ኹ
றཀྵࢀ᎖ JMJN`࣡࢟ኹࡼ2021ăJMJN`WDD ဟLjሢഗඡሢ
࢟ኹᆐ෦ཱྀᒋ211nWăᓞધࡵ211nW෦ཱྀᒋࡼ൝ඡሢᏖ
ᆐ WDD .! 2Wă
༿ዏৃᔥክQDCଐᒎฉቲݚLjཀྵۣᐅဉਜ਼EDᇙތ
્࣪ݙDT`࣡ࡼଶഗቧޘညছཷăୈ።భถణதᄴ
ݛᑳഗଶഗ࢟ᔜ)ན᎖ݧᒬଶഗऱါ*हᒙLj݀
ݧ༦ᒇࡼೌሣቲೌLjଶ࢟ހᔜݧLfmwjoଶೌހ
ऱါăྙਫᄴݛᑳഗࡴᄰ໐ମቆᄂऔࡴᄰLj
ᅄ9ᒦࡼ࢟ഗଶހறࣞଢ଼ࢅăᆐཀྵۣჅᎌ࢟ഗ࣒ᄰਭଶ
࢟ހᔜLjࡩᄴݛᑳഗਜ਼ଶ࢟ހᔜೝ࣡ࡼኹଢ଼ࡍ᎖ቆᄂ
औࡼᑵሶ࢟ኹဟLjቆᄂऔᒑᎧᄴݛᑳഗ
݀ೊ)ᅄ :*ăᓖፀǖᏴᆨ༽ౚሆLjᄴݛᑳഗࡼࡴᄰ
࢟ᔜᐐଝLjቆᄂऔࡼᑵሶ࢟ኹሆଢ଼ă
NPTGFUᐜདࣅ)EI`ĂEM`*
EI` ਜ਼EM`ᐜདࣅభॊܰᇢྜྷ3/1Bਜ਼4/4Bࡼ࢟ഗLjᑚ
ዹభཀྵۣᏴࡍ࢟ഗ።ᒦᄋ༓நࡼᐜདࣅăॳࣅࡼ
EI` ܟNPTGFUདࣅᎅCTU`࣡ᅪࡼऔ.࢟ྏ࢟
܃࢟ăऎᄴݛᑳഗདࣅEM`ᐌᒇᎅMEP6࢟ă
V+
MAX8732A
MAX8733A
DH_
LX_
OUT_
DL_
CS_
ᅄ9/ ݧଶ࢟ހᔜଶ࢟ހഗ)NBY9843B0NBY9844B*
ดݝདࣅ EM` ᆐࢅ࢟ຳࡼሆ౯ᄏᎌ 1/7Ω ࡼ࢜ቯࡴ
ᄰ࢟ᔜăᏴ࢟ঢஂ࢛Ⴅဍ໐ମLjᑚᒬࢅࡴᄰᔜఝభ
ऴᒏEM`୭ᎅ᎖ࢅܟᄴݛᑳഗNPTGFUࡼധࡵᐜ
ࡼྏቶẮऎۻ౯ăࡣဵLjᏴࡍ࢟ഗ።ᒦLjܟਜ਼
ࢅ ܟNPTGFU ࡼᔝభถ્ᐜ.ധࡼਭẮLj
࠭ऎଢ଼ࢅൈ݀ޘညࡴᒘFNJࡼࠃᅀ࢟ഗăᏴCTU`ࠈ
ೊጙৈ࢟ᔜ્ዓޠ ܟNPTGFU ࡼࡴᄰဟମ)ᄴဟጐ્ဧ
ൈଢ଼ࢅ*Ljࡣ્ݙ፬ሰਈࣥဟମ)ᅄ21*ă
5V
VIN
V+
MAX8732A
MAX8733A
BST
10Ω
DH_
DH
LX_
LX
OUT_
DL_
MAX8732A
MAX8733A
MAX8734A
CS_
ᅄ21/! ᄋఎਈஂ࢛ࡼဍႥࣞ
ᅄ:/! ࢯᑳቆᄂऔࡼೌऱါభဣሚৎறཀྵࡼ࢟ഗଶހ
______________________________________________________________________________________
21
NBY9843B0NBY9844B0NBY9845B
ࡩWPVU ᇢྜྷ࢟ഗဟLjঌሶሢഗถభऴᒏनሶ࢟ঢ࢟ഗ
ਭࡍăঌሶሢഗඡሢᏖᆐᑵሶሢഗࡼ231%Lj࠭ऎᏴࢯᑳ
JMJN`ဟభৌᔍᑵሶሢഗඡሢă
NBY9843B0NBY9844B0NBY9845B
᎖܊࢟۾ฎࡼൈĂ
႐ၒ߲ᓍ࢟Ꮞ఼ᒜ
ᔈး።ႌཌဟମ఼ᒜ࢟വପ၁EM`ਜ਼EI`དࣅLjጲऴᒏ
෭ৈGFUᏴጙৈGFUᅲཝਈࣥᒄ༄ࡴᄰăᑚᒬ఼ᒜऱါ
ถ৫း።੪ࣶNPTGFULjሿ߹ࠃᅀ࢟ഗLjዓߕିᒗᔢቃLj
ۣ݀ߒൈăᆐဧᔈး።ႌཌဟମ఼ᒜ࢟വᑵޟᔫLj
ᐜདࣅၒ߲ਜ਼NPTGFUᐜᒄମ።ݧࢅ࢟ᔜĂࢅ࢟
ঢᄰവǗ॥ᐌLjଶ࢟ހവ્ᏴNPTGFUᐜဣଔ྆ࡀᏴ
࢟ࡼ༽ౚሆᇙᆐĐਈࣥđᓨზă።ݧऻޟ༦ࡼ
ᔓሣ)NPTGFUᎧୈᒄମࡼ௦ಭᆐ2፞ࡁဟLjᔓሣࣞ።
ᆐ61njmᒗ211njm*ă
QPSĂVWMPਜ਼ดݝၫᔊྟࣅ
ࡩW,ဍࡵᏖ3/5WጲဟLjࣅ࢟আᆡ)QPS*Ljআᆡ་
ኹĂਭኹጲૺེਈࣥ৺ᑇჄࡀăࡩMEP6ࡼ࢟ኹࢅ᎖5W
)࢜ቯᒋ*ဟLjMEP6 ་ኹჄࢾ)VWMP*࢟വணᒏఎਈࣅᔫă
ྙਫPROۻணᒏLjᐌEM`ᆐࢅ࢟ຳǗྙਫPROۻဧถLjᐌ
EM`ᆐ࢟ຳăጙࡡWDD ި߲VWMPඡሢᒋ4/36W )࢜ቯ
ᒋ*݀༦ SFG ࠀ᎖ᆮࢾLjၒ߲࢟ኹఎဪဍăࣅ໐ମLj
ด ݝၫ ᔊ ྟ ࣅ ࢾ ဟ ဧ Ꮴ ࡼ ᔢ ࡍ ሢ ഗᓆ୍ᐐଝă
2/8ntࡼဍਭ߈ॊᆐ6ৈგǖ31%Ă51%Ă71%Ă91%ਜ਼
211%ă
ࡩME16ଢ଼ᒗࢅ᎖VWMPඡሢ)࢜ቯᒋ5W*ဟLjEI`ਜ਼EM`
ೂ૾ۻ౯ࢅLj݀༦ၒ߲ᆐᔜఝăࡩWDD ࢅ᎖4/36W! )࢜ቯ
ᒋ*ဟLjSFGਈࣥăࡩWDD ࢅ᎖QPSඡሢ)࢜ቯᒋ2W*ဟLj
EM`ۻᒮቤ౯ă
࢟Ꮞኙၒ߲)QHPPE*
QHPPE୷܈ߒኚପ၁ၒ߲࢟ኹࡼ་ኹᓨზăᏴਈࣥĂࡗ
૦ਜ਼ྟࣅ໐ମLjQHPPEۻ౯ࢅăࡩೝവၒ߲࢟ኹ࣒ࡉ
ࡵᇙ୷܈ތࡼඡሢဟLjQHPPEျह༦ၫᔊྟࣅᒫᒏă
ྙਫྀੜጙവၒ߲ۻਈࣥ܈ᑵޟᆮኹᒋࢅ21%ဟLjQHPPE
ܤᆐࢅ࢟ຳăQHPPEᆐᑞఎധၒ߲ăᓖፀǖQHPPEᎧ
PROࡼᓨზᇄਈă
৺ᑇۣઐ
NBY9843B0NBY9844B0NBY9845Bᄋਭኹ0་ኹ৺ᑇۣ
ઐถăདࣅ PRO ᆐࢅ࢟ຳభ૮৺ᑇۣઐถăདࣅ
PRO ᆐ࢟ຳభணᒏ৺ᑇۣઐถăጙࡡ৺ᑇۣઐถ
ۻ૮Ljকᇹୈభߒኚପ၁་ኹਜ਼ਭኹᓨზă
22
ਭኹۣઐ
ࡩၒ߲࢟ኹިਭࢾ࢟ኹ22%ဟLjਭኹ৺ᑇۣઐۻ૮ă
ᄴݛᑳഗጲ211% ࡼᐴహࡴ܈ᄰLj݀༦ܟNPTGFUਈ
ࣥăᑚဧࡻၒ߲࢟ྏႥह࢟Lj࠭ऎଢ଼ࢅၒ߲࢟ኹăၒ߲
࢟ኹభถଢ଼ᒗ࢟ຳጲሆăྙਫঌᏲݙถߌ၊ঌኹLjభᏴ
ၒ߲࣡हᒙጙৈൈቆᄂऔቲनሶὥᆡăᏴဣ
ଔ።ᒦLj࢟Ꮞ)࢟ߔ*ਜ਼ᅪݝܟఎਈᒄମᎌۣሙႋă
ྙਫਭኹ৺ᑇဵᎅ᎖ܟఎਈവऎLjᐌᄴݛᑳഗ
211%ࡴᄰဧ࢟ߔവᒗHOELjۣሙႋྌࣥLj࢟ߔۻ
ࣥఎăጙࡡਭኹ৺ᑇۻჄࢾLjᒑถᄰਭ߿खSHDNĂPO`
ᒮቤဗଝW,! )QPS*ࡼऱजဧআᆡă
་ኹۣઐ
ࡩၒ߲࢟ኹᎅᒙ࢟ኹሆଢ଼ 41%Lj༦ߒኚဟମࡍ᎖ 33nt
)་ኹਈࣥሿဟମ*ဟLj་ኹ৺ᑇۣઐۻ૮ăೝৈTNQT
ᄫᒏᔫăೝവၒ߲ఎဪह࢟)ݬह࢟ෝါ)ྟਈࣥ**ăࡩၒ
߲࢟ኹࢰൢᒗ 1/4W ဟLjᄴݛᑳഗࡴᄰLjၒ߲ὥᆡᒗ
HOEăభᄰਭ༤ધSHDNĂPO`ᒮቤဗଝW,! )QPS*༹
߹་ኹ৺ᑇჄࡀă
ེۣઐ
NBY9843B0NBY9844B0NBY9845Bᎌེਈۣࣥઐ࢟വLj
భܜୈᎅ᎖ਭེऎႼડăࡩஉᆨިਭ ,271 ° D ဟLj
ࣅེ৺ᑇۣઐăེਈࣥ໐ମჅᎌด࢟ݝവਈܕăྙਫ
MEP`࠭ဵݙPVU`ᔈၒ߲LjऎဵᏴW,࣡ဗଝၒྜྷ࢟
ኹLj݀࠭ MEP`ᇢ၃ᔢࡍ࢟ഗ)۞౪വ*LjᐌNBY9843B0
NBY9844B0NBY9845B્ࣅེਈۣࣥઐă૾ဧMEP`ဵ
࠭ PVU`ᔈLjMEP`ਭᏲጐ્ࡴᒘᔈఎਈࡼਭࡍLj
ᑚዹጐభถེਈۣࣥઐă߿खSHDNĂPO4ĂPO6
W,! )QPS*భᒫᒏེਈࣥᓨზă
ह࢟ෝါ)ྟਈࣥ*
ࡩPROᆐࢅ࢟ຳLj༦ୈᓞધᆐࡗ૦ෝါਈࣥෝါLj
ࡩၒ߲་ኹ৺ᑇჄࡀᒙᆡဟLjೝവၒ߲ᄰਭดݝ23Ωఎ
ਈ࣪ह࢟Ljᒇࡵၒ߲࢟ኹଢ଼ᆐ1/4Wăᓰۣ྆ߒᏴᔫ
ᓨზLjጲᄋறཀྵࡼඡሢਜ਼ਭኹۣઐăࡩೝവTNQTၒ߲
࣒ह࢟ᒗ1/4WဟLjEM`ᄴݛᑳഗདࣅۻ༓ᒜ౯ăᄴݛ
ᑳഗTNQTၒ߲ὥᆡᒗHOEăࡩPROᆐ࢟ຳဟLjTNQT
࣪ݙၒ߲ह࢟LjEM`ᄴݛᑳഗདࣅۣߒࢅ࢟ຳă
______________________________________________________________________________________
᎖܊࢟۾ฎࡼൈĂ
႐ၒ߲ᓍ࢟Ꮞ఼ᒜ
MODE
CONDITION
COMMENT
LDO5 < UVLO threshold
Transitions to discharge mode after a V+ POR and after REF becomes valid.
LDO5, LDO3, and REF remain active. DL_ is active if PRO is low.
SHDN = high, ON3 or ON5
enabled
Normal operation.
Overvoltage
Protection
Either output > 111% of
nominal level, PRO = low
DL_ is forced high. LDO3, LDO5 active. Exited by a V+ POR or by toggling
SHDN, ON3, or ON5.
Undervoltage
Protection
Either output < 70% of
nominal after 22ms timeout expires and output is
enabled, PRO = low
If PRO is low, DL_ is forced high after discharge mode terminates. LDO3,
LDO5 active. Exited by a V+ POR or by toggling SHDN, ON3, or ON5.
PRO is low and either
SMPS output is still high in
either standby mode or
shutdown mode
Discharge switch (12Ω) connects OUT_ to PGND. One output may still run
while the other is in discharge mode. Activates when LDO_ is in UVLO, or
transition to UVLO, standby, or shutdown has begun. LDO3, LDO5 active.
ON5, ON3 < startup
threshold, SHDN = high
DL_ stays high if PRO is low. LDO3, LDO5 active.
Shutdown
SHDN = low
All circuitry off.
Thermal Shutdown
TJ > +160°C
All circuitry off. Exited by V+ POR or cycling SHDN, ON3, or ON5.
Power-Up
Run
Discharge
Standby
ਈࣥෝါ
SHDN౯ࢅᒗறཀྵࡼSHDNሆଢ଼ዘ߿ख࢟ຳጲሆLjభဧ
NBY9843B0NBY9844B0NBY9845Bྜྷࢅਈࣥᓨზă
Ᏼਈࣥෝါሆ NBY9843B0NBY9844B0NBY9845B ஞሿ
7μBࡼஸზ࢟ഗăਈࣥෝါሆᓰᏎۻਈܕLjፐࠥᅓ߲ਈ
ࣥෝါࡼඡሢறࣞ୷ࢅăᆐ೫ཀྵۣᑵޟࣅLj።SHDN
౯ᒗࡍ᎖ 3W! )SHDNၒྜྷဍዘ߿ख࢟ຳ*ăྦᇧᆃᔈ
ࣅਈࣥਜ਼ࣅLjభ SHDNೌᒗ W,ăྙਫ PROᆐࢅ࢟
ຳLjᏴྜྷᑞਈࣥᒄ༄LjೝᔝTNQTၒ߲ۻጙৈࡴᄰ࢟ᔜ
ᆐ23Ω ࡼఎਈह࢟ᒗ1/4Wăறࣞࡼ2W! SHDNሆଢ଼ዘඡ
ሢభଶހ෭ৈᄂࢾࡼෝผ࢟ኹ݀ਈࣥୈăጙࡡক
ୈۻਈࣥઁLj2/7Wࡼဍዘඡሢۻ૮Ljభᆐࡍࣶၫ።
ᄋᔗ৫ࡼᒣૄăྦኊᐐଝᒣૄLjభጲᎅSFGMEP`
ཀྵࢾ་ኹඡሢLjਈࣥෝါሆSFGਜ਼MEP`ܤᆐ1Wă
ܭ5/! ࢟ၿኔ
SHDN
(V)
VON3
(V)
VON5
(V)
LDO5
LDO3
5V SMPS
3V SMPS
Low
X
X
Off
Off
Off
Off
“> 2.4” => High
Low
Low
On
On (after REF powers up)
Off
Off
“> 2.4” => High
High
High
On
On (after REF powers up)
On
On
“> 2.4” => High
High
Low
On
On (after REF powers up)
Off
On
“> 2.4” => High
Low
High
On
On (after REF powers up)
On
Off
“> 2.4” => High
High
REF
On
On (after REF powers up)
On (after 3V SMPS is up)
On
“> 2.4” => High
REF
High
On
On (after REF powers up)
On
On (after 5V SMPS is up)
______________________________________________________________________________________
23
NBY9843B0NBY9844B0NBY9845B
ܭ4/! ᔫෝါᑞᒋܭ
࢟ၿኔਜ਼ఎ0ਈ఼ᒜ)PO4ĂPO6*
PO4ਜ਼PO6భ᎖఼ᒜTNQTࡼ࢟ၿኔăPO4PO6࢟
ኹဍᒗࡍ᎖3/5WဟLjభጲဧถ࣪።ࡼၒ߲ăPO4PO6࢟
ኹଢ଼ᒗ2/7WጲሆဟLjభጲணᒏ࣪።ࡼၒ߲ă
PO4PO6SFGဟLjభ༓ᒜ࣪።ࡼၒ߲Ᏼᅪጙവၒ߲
ᆮࢾጲ༄ࠀ᎖ਈࣥᓨზLjᅪጙവၒ߲ᆮࢾઁࣅᔫă
ጙৈ TNQT ਈࣥĂୈਈࣥĂखည৺ᑇᑗ MEP6 खည
་ኹჄࢾጲ༄LjऔৈTNQTጙᒇࠀ᎖ᔫᓨზăࡩጙ
ᔝ࢟ᏎۻਈࣥဟLjೝᔝ࢟Ꮞೂ૾ྜྷࢬ࢟߈ኔăདࣅ
PO`ࢅ᎖1/9Wభ༹߹ਭኹĂ་ኹૺེ৺ᑇჄࡀă
భࢯஂࡼၒ߲नౣ)ၷෝGC*
GC` ೌᒗ HOE భኡᐋᎾࡼ TNQT ৼࢾၒ߲࢟ኹ
)4/4W ਜ਼6W*ăྦGC`ೌࡵPVU`ਜ਼HOEᒄମࡼ࢟ᔜॊ
ኹLjᐌభᏴ 3W ᒗ 6/6W पᆍดࢯஂ࣪።ࡼၒ߲࢟ኹ
)ᅄ22*ăS3ኡན21lΩᔧᎎLjS2ࡼଐႯါྙሆǖ
⎛
⎜⎜
⎝
NBY9843B0NBY9844B0NBY9845B
᎖܊࢟۾ฎࡼൈĂ
႐ၒ߲ᓍ࢟Ꮞ఼ᒜ
⎛V
OUT _
R1 = R2 × ⎜
−1
⎜ V
⎝ FB
V+
DH_
VOUT_
DL_
GND
R1
OUT_
FB_
R2
````````````````````````````````ଐݛᒾ
Ᏼኡᐋ࢟ঢૺᆬ݆࢟ഗ)܈MJS*ᒄ༄Lj၅ሌገཀྵࢾၒྜྷ
࢟ኹपᆍਜ਼ᔢࡍঌᏲ࢟ഗăጲሆ႐ৈፐႤ્፬ሰࡵ
ࡼଐǖ
2* ၒྜྷ࢟ኹपᆍǖၒྜྷ࢟ኹࡼᔢࡍᒋ)W,)NBY**ܘኍး።
BDး࢟ኹࡼᔢࡍᒋăᔢቃᒋ)W,)NJO**ܘኍఠள
ਭೌĂۣሙႋጲૺ࢟ߔኡᐋఎਈଢ଼ኹࡼᔢࢅၒྜྷ
࢟ኹăၒྜྷ࢟ኹᏗࢅൈᏗă
3* ᔢࡍঌᏲ࢟ഗăख़ᒋঌᏲ࢟ഗ)J MPBE)NBY**ཀྵࢾ೫Ꮔ
ୈࡼၾဟ።ೆਜ਼݆ገཇLjፐऎ፬ሰၒ߲࢟ྏࡼኡᐋĂ
࢟ঢࡼۥਜ਼ᒎܪਜ਼ሢഗ࢟വࡼଐăೌኚঌᏲ࢟ഗ
)JMPBE*ࢾ೫ེ።ೆLjᒜᏖᓹၒྜྷ࢟ྏĂNPTGFUጲ
ૺᓍገखེᏄୈࡼኡᐋă
ᒦ WGC >! 3W! )߂ܪᒋ*ă
MAX8732A
MAX8733A
MAX8734A
ݧభࢯஂၒ߲ෝါဟLj። 4/4W! TNQT ၒ߲ᒙࡻ܈
6W! TNQT ၒ߲ࢅጙቋăᒑᎌࡩ PVU6 ࢟ኹࡍ᎖ MEP6 ࡼᔈ
ఎਈඡሢ)5/67W*ဟLjݣถᄰਭดݝఎਈMEP6ೌᒗ
PVU6ăᄴዹLjᒑᎌࡩPVU4࢟ኹ᎖MEP4ࡼᔈఎਈඡ
ሢ)3/:2W*ဟLjݣถᄰਭดݝఎਈ MEP4 ೌᒗ PVU4ă
ݧৼࢾၒ߲࢟ኹဟᔈ࢟വᔢᆐᎌăጙࡡ MEP` ᎅ
PVU`ᔈLjดݝሣቶᆮኹਈܕăᑚዹభᏴၒྜྷ࢟ኹ
୷ဟଢ଼ࢅดݝLjᄋൈă
4* ఎਈຫൈăఎਈຫൈࡼኡᐋ።ཚੰఠߛࡁࡍቃਜ਼
ൈăᔢଛຫൈᏴ੪ࡍ߈ࣞན᎖ᔢࡍၒྜྷ࢟ኹਜ਼
NPTGFU ఎਈႼăNBY9843Bࡼ6W! TNQTࡼऄࢾఎ
ਈຫൈᆐ311lI{Lj4/4W!TNQTࡼऄࢾఎਈຫൈᆐ411lI{ă
NBY9844B ࡼ 6W! TNQT ࡼऄࢾఎਈຫൈᆐ 511lI{Lj
4/4W TNQTࡼऄࢾఎਈຫൈᆐ611lI{ăNBY9845Bࡼ
ఎਈຫൈభᄰਭ୭ኡᐋă
5* ࢟ঢᆬ݆࢟ഗ)܈MJS*ăMJS ဵख़. ख़ᆬ݆࢟ഗᎧຳ
࢟ঢ࢟ഗᒄ܈ăᏴཀྵࢾ࢟ঢᆬ݆࢟ഗ܈ဟLj።Ᏼߛࡁ
Ꭷൈᒄମཚੰఠă࢟ঢᒋ୷ࢅဟLjᆬ݆࢟ഗ୷ࡍLj
ߛࡁ୷ቃLjࡣൈ୷ࢅLj݀ᎌ୷ࡼၒ߲ᐅဉăဣ
ࡼᔢቃ࢟ঢᒋ።ဧ࢟വᔫᏴஏࠅࡴෝါ)ঌᏲ
ᔢࡍဟ࢟ঢ࢟ഗᏴඛৈᒲ໐ੑਙഃDžăኡན܈ᑚৈ
ஏᒋથࢅࡼ࢟ঢᇄፄ᎖ߛࡁࡼጙିݛቃă
ᅄ22/! ಽ࢟ᔜॊኹᒙWPVU` ࢟ኹ
24
______________________________________________________________________________________
᎖܊࢟۾ฎࡼൈĂ
႐ၒ߲ᓍ࢟Ꮞ఼ᒜ
࢟ঢኡᐋ
ఎਈຫൈ)ࡴᄰဟମ*ਜ਼࢟ঢᔫ࢛)ᆬ݆࢟ഗ܈MJS*ࢾ
೫࢟ঢᒋࡼࡍቃLjਈᇹྙሆǖ
L =
(
VOUT_ V + − VOUT_
)
V + × f × LIR × ILOAD(MAX)
ಿྙǖ JMPBE)NBY* = 6BLjW,! = 23WLjWPVU6 = 6WLjg! =
311lI{Lj46%ࡼᆬ݆࢟ഗMJS! = 1/46ဟLjᎌǖ
L=
(
5V 12V − 5V
)
12V × 200kHz × 0.35 × 5A
= 8.3μH
Ᏼ൸ᔗߛࡁገཇࡼ༄ᄋሆLj።ኡནED࢟ᔜభถࢅࡼࢅ
Ⴜ࢟ঢăᄤድࠟበ࢟ঢᄰဵޟᔢଛኡᐋLjࠟበ።কᔗ
৫ࡍLjጲཀྵۣᏴख़ᒋ࢟ঢ࢟ഗ)JQFBL*ሆۥ્ݙਜ਼ǖ
IPEAK = ILOAD(MAX) + [(LIR / 2) x ILOAD(MAX)]
࢟ঢᆬ݆࢟ഗጐ્࣪ၾზሰ።ᄂቶޘည፬ሰLjᄂܰဵᏴ
W,! .! WPVU` ތᒋ୷ቃဟă୷ࢅࡼ࢟ঢᒋᏤ࢟ঢ࢟ഗৎ
ࣅڼLjޡݗၒ߲݆࢟ྏᎅ᎖ঌᏲᅃᐐऎߥۻᔓࡼ
࢟ăၒ߲ၾზ࢟ኹ)WTBH*ࡼख़ᒋᑩ७ጐᎧᔢࡍᐴహ܈ᎌ
ਈLjభጲোࡴᄰဟମਜ਼ᔢቃਈࣥဟମଐႯǖ
VSAG =
(ΔILOAD(MAX) )
2
⎛ V
⎞
OUT _
× L ⎜K
+ t OFF(MIN) ⎟
⎜
⎟
V+
⎝
⎠
⎡ ⎛ V+− V
⎤
⎞
OUT _
− t OFF(MIN) ⎥
2 × COUT × VOUT _ ⎢K⎜
⎟
⎟
⎢ ⎜⎝
⎥
V+
⎠
⎣
⎦
ᒦᔢቃਈࣥဟମ = 1/461μt!)ᔢࡍᒋ*LjLభ࠭ܭ3ᒦࡻއă
ሢഗᒙ
ᔢࢅሢഗඡሢܘኍᔗ৫ࡍLjጲཀྵۣࡩሢഗᒋᆐތप
ᆍดࡼᔢቃᒋဟLjሢഗඡሢ྆ถ൸ᔗᔢࡍঌᏲ࢟ഗገཇLj
࢟ঢ࢟ഗࡼĐ৸đᒋᆐ J MPBE)NBY*ିབྷᆬ݆࢟ഗࡼጙۍLj
ፐࠥǖ
ILIMIT(LOW) > ILOAD(MAX) - [(LIR / 2) x ILOAD(MAX)]
ᒦJMJNJU)MPX*ࢀ᎖ᔢቃሢഗඡሢ࢟ኹ߹ጲO30O5ࡼSET)PO*
)NBY9845B*ă࣪᎖NBY9843B0NBY9844B0NBY9845BLjᔢ
ቃሢഗඡሢ࢟ኹᆐ:4nW! )JMJN`! = WDD*ă።ݧ NPTGFU
O30O5 ၫᓾ೯ᒦᔢ༽ތౚሆࡼ S ET)PO* ᔢࡍᒋLjఠࡵ
S ET)PO* ્ႲᆨࣞࡼဍऎᐐࡍLjથ።ഔᎌጙࢾࡼᎽă
ጙৈ୷ੑࡼਖᐌဵᆨࣞඛᐐଝ2°DLj࢟ᔜᒋᐐଝ1/6%ă
ጲ 6B።࢟വᆐಿLjᆨሆࡼᔢࡍSET)PO*! = 23nΩLjᐌᎌǖ
ILIMIT(LOW) = 93mV / 12mΩ > 5A - (0.35 / 2) 5A
7.75A > 4.125A
8/86Bࡍ᎖5/236Bࡼ৸࢟ഗLjፐࠥݧৼࢾࡼ211nWሢഗ
ඡሢถၒ߲6B൸Ᏺ࢟ഗă
ᄴݛᑳഗࡼᏎᄰਭጙৈ࢟ഗଶ࢟ހᔜ HOE
)NBY9843B0NBY9844B*Lj݀DT`ᒗকஂ࢛Ljభጲ
ᒙୈࡼሢഗăNBY9843B0NBY9844B0NBY9845Bݧଶ
࢟ހᔜሢഗLjऎဵݙဧ O30O5 ࡼ S ET)PO*ăଶ࢟ހᔜࡼ
ᔢࡍᒋభᎅሆါଐႯǖ
ILIM_ = 93mV / RSENSE
ၒ߲࢟ྏኡᐋ
ၒ߲݆࢟ྏࡼࢀࠈೊ࢟ᔜ)FTS*ܘኍᔗ৫ࢅLjጲ൸ᔗ
ၒ߲ᆬ݆ਜ਼ঌᏲၾࡼܤገཇLjᄴဟFTSጐݙถვࢅLjጲ
൸ᔗᆮࢾቶࡼኊཇăၒ߲࢟ྏࡼྏᒋ።ᔗ৫ࡍLjጲܣถ
৫ᇢ၃࢟ঢ࠭൸ᏲᓨზᓞધࡵహᏲᓨზဟျहࡼ࢟ถLj
ऎ߿્ݙखਭኹ৺ᑇܕჄăᏴၒ߲ࡀᏴ௭ೲঌᏲၾࡼܤ
።ᒦLjၒ߲࢟ྏࡼߛࡁན᎖ჅኊFTSࡼࡍቃLjገཇঌ
ᏲၾܤဟFTSݙ።ဧၒ߲ޘညਭࡍࡼࢰൢăྙਫᎌሢ
ྏᒋࡼ࢟ኹࢰൢLjᐌᎌǖ
RESR ≤
VDIP
ILOAD(MAX)
ᒦ W EJQ ဵჅᏤࡼᔢࡍၾზ࢟ኹࢰൢᒋăᏴ DQV ጲᅪ
ࡼ።ᒦLjၒ߲࢟ྏࡼߛࡁᄰޟན᎖ኊገࣶࡍࡼFTSLj
ጲၒ߲࢟ኹᆬ݆ۣߒᏴభ၊ࡼၺຳă
______________________________________________________________________________________
25
NBY9843B0NBY9844B0NBY9845B
NBY9843B0NBY9844B0NBY9845B ࡼᄢ൴ߡ఼ᒜ࢟വ
)SKIP = HOE*Ᏼஏࠅࡴ࢛ဟࣅᄢ൴ߡෝါLjፐࠥLj
࢟ঢᔫ࢛ጐࢾ೫QXN0QGNᓞધဟࡼঌᏲ࢟ഗᒋăᔢ
ଛᔫ࢛ᄰޟᆡ᎖31&ࡵ61&ࡼᆬ݆࢟ഗă
NBY9843B0NBY9844B0NBY9845B
᎖܊࢟۾ฎࡼൈĂ
႐ၒ߲ᓍ࢟Ꮞ఼ᒜ
RESR ≤
VP−P
ESR =
LIR × ILOAD(MAX)
ᒦWQ.Q ဵၒ߲࢟ኹᆬ݆ख़.ख़ᒋăဣଔჅኊࡼ࢟ྏᒋᎧ
൸ᔗࢅFTSገཇჅኊࡼᇕಯߛࡁᎌਈLjથᎧ࢟ྏࡼછኧ
ಢቯᎌਈăፐࠥLjᄰޟᏴኡᐋ࢟ྏဟLj၅ሌఠࡼဵ
FTS ਜ਼ऄࢾ࢟ኹLjऎྏ࢟ဵݙᒋࡍቃ)কᏇᐌး᎖ᶉ
࢟ྏĂPT.DPOૺಢቯࡼ࢟ஊ࢟ྏ*ă
ࡩݧྏᒋ୷ቃࡼ݆࢟ྏྙᄏ࢟ྏဟLjߛࡁኡ
ᐋ።ۣᑺᏴިဉෝါሆLjঌᏲၾܤဟࡼ W TBH ਜ਼ W TPBS ݙ
્߿ख་ኹਜ਼ਭኹ৺ᑇܕჄă
ၒྜྷ.ၒ߲࢟ኹ୷ތቃဟ)WJO 0! WPVU < 3*Ljኊገऄᅪᐐଝ
ၒ߲࢟ྏཀྵۣިဉෝါሆࡼᆮࢾቶਜ਼୷ࡼൈă
ᎅ࢟ঢถჅࡼਭߡభږሆါଐႯǖ
VSOAR =
IPEAK 2 L
2COUT VOUT _
ᒦ-! JQFBL ဵ࢟ঢࡼख़ᒋ࢟ഗă
ᆮࢾቶఠ
FTS ഃ࢛)gFTS*ਜ਼ఎਈຫൈ)g*ࡼሤ࣪ᆡᒙࢾ೫ᇹᄻࡼᆮ
ࢾቶăݙᆮࢾ࢛ᎅሆါ߲ǖ
f
fESR ≤
π
ᒦLj
fESR =
LIR × ILOAD
ᒦMJSဵ࢟ঢᆬ݆࢟ഗ܈LjJMPBE ဵຳᒇഗঌᏲ࢟ഗă
ན MJS! = 1/46LjຳঌᏲ࢟ഗᆐ6BဟLj൸ᔗ61nWQ.Q ᆬ݆
ჅኊࡼFTSᆐ39nΩă
ݙገݙଝఠᏴႥनౣၒྜྷ࣡)PVU` ᒗ HOE ဵดन
ౣLjGC` ॊኹ࢛ᆐᅪनౣ*ᒇྜྷࡍྏࡼჿࠣ࢟ྏLj
ጲཀྵۣᆮࢾቶăፐᆐࡍྏჿࠣ࢟ྏᎌ୷ࡼFTSഃ࢛
ຫൈLj્ဧ࢟വࠀ᎖ݙᆮࢾᔫᓨზăᐐଝጙᒑॊಭါ
࢟ᔜLj࢟ྏहᒙᏴ࢟ঢਜ਼ PVU` ஂ࢛ሆᎊଂ፞ࡁࠀLj
ጐభጲখ࿖ᆮࢾቶă
ݙᆮࢾᔫᎌೝᒬሤਈࡣݙᄴࡼܭሚऱါǖၷ൴ߡ
ਜ਼Ⴅनౣણവݙᆮࢾăၒ߲ᐅဉਭቃࡼFTS્࣒ࡴᒘ
ၷ൴ߡሚሷăਭቃࡼFTSݙถᏴၒ߲ᒦޘည७ࣞᔗ৫ࡍࡼ
ቓຸ࢟ኹăᑚ્ဧᇙ୷܈ތᏴ461otࡼᔢਈࣥဟମ
ઁೂ૾ࡇᇙ߿खጙৈቤࡼᒲ໐ăၷ൴ߡࡴᒘၒ߲ᆬ݆
ᐐࡍLjጐᎾာᓹਭࢅࡼFTS೫ણവࡼݙᆮࢾăखည࢟
ᏎঌᏲၾઁܤLjݙᆮࢾࡼણവ્Ᏼၒ߲ޘညᑩ
ᑩഅLj݀߿खਭኹۣઐჄࡀࡴᒘၒ߲࢟ኹࢰൢࡵྏ
ሢጲሆă
ଶއᆮࢾቶᔢ଼ࡼऱजဵཱུঌᏲኸႥ࠭ഃܤᆐᔢࡍ)ݬ
NBY9845Bຶৰۇၫᓾ೯*Ljᄴဟᔄᇼފၒ߲࢟ኹ
ᆬ݆ࡼ۞Ljఘဵ॥߲ሚਭߡਜ਼ᑩăጙৈBD࢟ഗყ
ᄿପ၁࢟ঢ࢟ഗጐ੪ᎌۑᓐăᏘሰ።ࡼ0ሆߡᒄ
ઁࡼᑩݙ።ިਭጙৈᒲ໐ă
ၒྜྷ࢟ྏኡᐋ
1
2π RESR COUT
Ᏼఎਈຫൈᆐ411lI{ࡼ࢜ቯ።ᒦLjFTSഃ࢛ຫൈܘኍᏐ
ࢅ᎖:6lI{Ljᔢੑࢅ᎖61lI{ă༄ጯࡻࡵਓम።ࡼࢅ
FTS ࢟ྏ)ᄂܰဵᄏᶉ࢟ྏ*ᄰޟᎌࢅ᎖41lI{ࡼ
FTSഃ࢛ຫൈăᏴ࢟ঢኡᐋݝॊ߲ࡼଐपಿᒦLj൸ᔗ
ᄂࢾᆬ݆࢟ኹገཇჅኊࡼFTSᆐǖ
26
VRIPPLE(P−P)
ၒྜྷ࢟ྏܘኍ൸ᔗᎅఎਈ࢟ഗࡼၒྜྷᆬ݆࢟ഗ)JSNT*
ገཇLjNBY9843B0NBY9844B0NBY9845Bၷᄰࡸఎਈᆮኹ
ᔫᏴݙᄴࡼຫൈăᑚዹభဧೝৈఎਈࡼᇢ၃࢟ഗ൴
ߡሤઑୣࡇLjჁ೫ඣᒮࢶࡼဟମ)ᒮࢶဟᇢ၃࢟ഗሤ
ଝ*ăᎧೝৈᄴሤ TNQT ሤ܈Ljၒྜྷ SNT ࢟ഗገቃࡻࣶă
ၒྜྷSNT࢟ഗႲঌᏲਜ਼ၒྜྷ࢟ኹܤછऎܤછă
______________________________________________________________________________________
᎖܊࢟۾ฎࡼൈĂ
႐ၒ߲ᓍ࢟Ꮞ఼ᒜ
(
⎛
⎜ VOUT _ V + − VOUT _
IRMS ≈ ILOAD ⎜
V+
⎜
⎝
) ⎞⎟
⎟
⎟
⎠
ࡩW,!= 3!y!WPVU`)E!= 61%*ဟLjJSNT ᎌᔢࡍᒋJMPBE! 0!3ă
ၒྜྷ࢟ྏࡼ FTS ဵࢾ࢟ྏࡼਈፐႤăൈႼ
)JSNT3 y! FTS*ဧ࢟ྏखེLj݀ଢ଼ࢅൈăऻᶉᒠ࢟ྏ)ჿ
ࠣ PT.DPO*ᎌ୷ࢅࡼFTSLj݀ถ৫ߌ၊࢟ဟࡼ፻
࢟ഗLjဵଐဟࡼ၅ኡăᆐ೫ࡻࡵᔢଛࡼᆮࢾቶਜ਼ဧ
၇ෘLj።ࡩኡᐋᏴၒྜྷ࢟ഗSNTपᆍดᆨဍቃ᎖,21°Dࡼ
࢟ྏăܟఎਈࡼധገࠥ܋ణதLjጲੰৢࡼၒྜྷ
വ࢟ྏă
ൈNPTGFUኡᐋ
ጲሆNPTGFUኡᐋᒎฉᓹᒮᄀ൙Ᏼݧኹ)> 31W*! BDး
ᄋঌᏲ࢟ഗ)> 6B*ဟჅᎲࡵࡼᄞᐵăᄰޟቃ࢟ഗ
።ሤ࣪ገཇࢅጙቋă
ᆐࡻᔢൈLj።ኡᐋᏴ࢜ቯ࢟ߔ࢟ኹሆࡴᄰႼᎧ
ఎਈႼሤࢀࡼܟNPTGFU! )O20O4*ăཀྵۣᔢቃၒྜྷ࢟
ኹဟLjࡴᄰႼިݙਭॖᓤࡼྲེሢި߲ᔐᄏྲེ
ᎾႯăཀྵۣᔢࡍၒྜྷ࢟ኹဟLjࡴᄰႼᎧఎਈႼᒄਜ਼
ިݙਭॖᓤᏤᒋި߲ᔐᄏྲེᎾႯă
ᄴݛᑳഗ)O30O5*ࡼSET)PO*።భถࢅăཀྵۣܟఎਈ
ࡌఎဟLj્ݙᎅ᎖ധ.ᐜည࢟ྏऎᐜ౯Lj࠭
ऎୣࡴބᄰᆰᄌăᄴݛᑳഗࡼఎਈႼభጲLj
ፐᆐᏴcvdlᅠແᒦLjဵഃ࢟ኹఎਈୈă
NPTGFU
ᐴహࡵࡉ܈ሢဟLjࠅࡴႼᔢࡍă࣪᎖ ܟNPTGFU
ႁLj࢟ߔ࢟ኹᔢቃဟ NPTGFU! S ET)PO*ࡼ)QE*
ᔢࡍǖ
PD(NH
⎞
⎛ V
2
OUT _
⎟ ILOAD RDS(ON)
) = ⎜
⎜ VIN(MIN) ⎟
⎠
⎝
(
)
ጙ༽ۅౚሆLjݧቃࡼܟNPTGFUభଢ଼ࢅၒྜྷ࢟ኹဟ
ࡼఎਈႼăऎLjᎅ᎖ॖᓤྲถೆࡼሢᒜLjSET)PO*
ݙถვࡍLjᑚ᎒ሢᒜ೫NPTGFUݙถვቃăࡩఎਈ)BD*Ⴜ
ࢀ᎖ࠅࡴ)SET)PO**Ⴜဟᆐᔢଛᓨზă
ၒྜྷ࢟ߔ࢟ኹᔢࡍဟLjᎅ᎖ఎਈႼါᒦࡼຳऱሲ
DW 3 y! gLj ܟNPTGFU ࡼఎਈႼ્߅ᆐྲེᆰᄌࡼ
નăྦኡᐋࡼܟNPTGFUᏴࢅ࢟ߔ࢟ኹဟᎌᔗ৫ࢅࡼ
SET)PO*LjࡣᏴဗଝW,)NBY*ဟེޟऻࡻܤLjᐌ።ఠৎધ
ܟNPTGFUă
ଐႯOI )O20O4*ࡼఎਈႼဵ੪౩ซࡼLjፐᆐૺࡵጙ
ቋ੪ซછࡼĂ፬ሰࡴᄰਜ਼ਈࣥဟମࡼፐႤăᑚቋፐႤ
۞౪ᐜด࢟ݝᔜĂᐜ࢟Ăඡሢ࢟ኹĂᏎ࢟ঢጲ
ૺQDCݚᄂቶࢀăሆෂࡼఎਈႼଐႯᒑဵጙৈऻ࠰ޟ
ࡼৰଐLjݙถᄐࡔဣዩ၀ހ၂LjᔢੑᏴOI )O20O4*ڔ
ᓤེ࢟๔ቲዩᑺǖ
PD(NH
)=
COSS (VIN(MAX) )2 fSW
2
+
VIN(MAX)ILOADQG(SW)fSW
IGATE
ᒦ DPTT ဵOI )O20O4*ࡼၒ߲࢟ྏLjRH)TX*ဵOI ࡼᐜ
࢟LjJHBUF ဵᐜདࣅᏎ߲0ᇢྜྷ࢟ഗࡼख़ᒋă
࣪᎖ᄴݛᑳഗႁLj࢟ߔ࢟ኹᔢࡍဟᔢࡍǖ
⎛
VOUT _ ⎞
2
PD (NL ) = ⎜1 −
⎟ ILOAD RDS(ON)
V
IN(MAX) ⎠
⎝
ᔢࡍNPTGFU߲ሚᏴዏᒮਭᏲ༽ౚሆLjࠥဟঌᏲ࢟ഗ
ࡍ᎖JMPBE)NBY*Ljࡣᆚިਭሢᒜ࢟ഗLjݙᔗጲ߿ख৺ᑇ
ܕჄăᆐ೫ཀྵۣڔཝᔫ᎖ᑚᒬঌᏲᄟୈሆLjᏴ࢟വ
ଐᒦ።ഔᎌᔗ৫ࡼଐă
ILOAD = ILIMIT(HIGH) + (LIR / 2 ) x ILOAD(MAX)
ᒦJMJNJU)IJHI*ᆐሢഗ࢟വᏤࡼᔢࡍ৸࢟ഗLjᒦఠ
೫ඡሢྏތਜ਼࢟ᔜມތă
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27
NBY9843B0NBY9844B0NBY9845B
࣪᎖ৈTNQTႁLjၒྜྷ࢟ྏࡼᔢࡍ࢟ഗSNTభᎅሆါ
߲ǖ
NBY9843B0NBY9844B0NBY9845B
᎖܊࢟۾ฎࡼൈĂ
႐ၒ߲ᓍ࢟Ꮞ఼ᒜ
ᑳഗኡᐋ
ܟఎਈਈࣥဟLj࢟ഗ࠭ഗࡵೝৈNPTGFUਜ਼࢟ঢࡼೌ
࢛ăፐࠥLjఎਈஂ࢛ࡼቶሤ࣪ᆐঌăᏴೝৈ༤ધ
ዘࠀLjೝৈఎਈਈࣥဟ)ႌཌ*ক࢟ኹᏖᆐ.1/8W! )औ
ࡼኹଢ଼*ăࢅܟఎਈࡴᄰဟকኹଢ଼ᆐJM y! SET)PO*ă
ᄴݛᑳഗೝ࣡ࡼᑳഗὥᆡᔫLjభᏴܟNPTGFU
ਈࣥਜ਼ᄴݛᑳഗࡴᄰᒄମࡼႌཌဟମ༃ᒜ࢟ঢ࢟ኹࡼ
ঌሶࣅڼăྙਫൈဵݙ၅ገࡼLjNPTGFUᄏดࡼႥਘ
औጐభጲࡵὥᆡऔࡼᔫăጙৈቆᄂऔ
Ꭷᄏऔ݀ೊLjభጲିቃᑵሶኹଢ଼Ljऴᒏ O30O5
NPTGFUࡼᄏऔᏴႌཌဟମดࡴᄰăᄰޟLjᅪऔ
భဧൈᄋ2%ᒗ3%ăభጲݧऄࢾᒇഗ࢟ഗࢀ᎖ঌ
Ᏺ࢟ഗ204ࡼቆᄂऔăಿྙLjঌᏲ࢟ഗᔢࡍ2/6BဟLj
ኡ NCS1641! )ऄࢾᒋ611nB*LjঌᏲ࢟ഗᔢࡍ4Bဟኡ
2O692:LjঌᏲ࢟ഗࡉ21Bဟኡ2O6933ăᑳഗऄࢾन
ሶૣࠃ࢟ኹܘኍᒗࢀ᎖ᔢࡍၒྜྷ࢟ኹLjᔢੑᎌ31%ࡼଢ଼
ऄፐၫă
ᔈऔ
ቃቧऔྙ 2O5259 Ᏼࡍࣶၫ።ᒦᔫੑăྙਫ
ၒྜྷ࢟ኹଢ଼ࢅᒗ7WጲሆLjݧቃቯ)31nB*ቆᄂऔ
భᄋൈਜ਼খ࿖ኹތᄂቶăݙገဧࡍൈऔLj
ྙ2O69282O5112Ljፐᆐඣ୷ࡍࡼஉ࢟ྏ્ဧMEP6ࡼ
࢟ኹਭă
ᏲᐐࡍࡼถೆLjকᒋ።কဪᒫࡍ᎖2ăi܆த2ဟLjጐဵ
࣪ኹ࢛ތLjᏴඛৈఎਈᒲ໐ด࢟ঢ࢟ഗᄋဍࡼถೆܤ
ࢅLjྙਫݙဧৎࣶࡼၒ߲࢟ྏLjWTBH ્ࡍࡍᐐଝă
ಯࡼ i ᔢቃᒋᆐ 2/6LjࡣభጲሆࢯᑳLjጲܣᏴ W TBH Ă
ၒ߲࢟ྏਜ਼ᔢቃᔫ࢟ኹମནࡻৎੑࡼຳੰăiᒋࢾઁLj
োጲሆါଐႯᔢቃᔫ࢟ኹǖ
V + (MIN) =
(VOUT _ + VDROP1 )
⎛t
⎞
OFF (MIN) × h
⎟
1− ⎜
⎜
⎟
K
⎝
⎠
+ VDROP2 − VDROP1
ᒦ W ESPQ2 ਜ਼ W ESPQ3 ဵह࢟ਜ਼ߠ࢟ᄰവᒦࡼညኹଢ଼
)ݬࡴᄰဟମᆮზ )uPO**Lj uPGG)NJO* ᏴFDܭᒦ߲LjL
ནᔈ ܭ3ăi! = 2ဟଐႯࡻࡵ࣪ᔢቃၒྜྷ࢟ኹă
ྙਫଐႯ߲ࡼW,)NJO*ࡍ᎖Ⴥኊࡼᔢቃၒྜྷ࢟ኹLjᐌܘኍ
ଢ଼ࢅᔫຫൈLjᄰਭᄋiਜ਼ၒ߲࢟ྏᒋࡻࡵభጲ
၊ࡼ W TBH ăྙਫభถᔫᏴࢅኹތᄟୈሆLjᐌ።ଐႯ
WTBHLjཀྵཱྀဵ॥ᎌᔗ৫ࡼၾზሰ።ă
ኹތଐဣಿ
NBY9844B;! ఠWPVU6 = 6WLjgTX = 511lI{LjL! = 3/36μtLj
uPGG)NJO* = 461otLjWESPQ2 = WESPQ3 = 211nWLji! = 2/6Lj
ᔢቃW,ᆐǖ
````````````````````````````````።ቧᇦ
ࢅኹތቶถ
ೌኚࡴᄰᔫෝါሆLjၒ߲࢟ኹࢯஂपᆍ၊ሢ᎖ᔢቃਈ
ࣥဟମᆮზ࢟വLjਈࣥဟମݙభࢯஂLjᔢࡍᒋᆐ
461otăభࢯनౣෝါሆLjᆐ೫ࡻᔢଛࡼࢅኹଢ଼ቶถLj
።ݧႥࣞ୷ൻࡼ 6W! TNQT ဣሚೝᔝ࢟Ꮞᒦ࢟ኹ୷ࡼ
ጙᔝăᔫ᎖ࢅၒྜྷ࢟ኹဟLjሢᐴహܘ܈ኍোᔢડ
༽ౚሆࡼࡴᄰဟମਜ਼ਈࣥဟମቲଐႯăᒜᐆྏૺތ
ดࠅݝၒዓߕ્ uPO LፐᔇྜྷᇙތăᄴဟLjܘኍಐǖ
cvdlࢯஂதᔢቃኹ࢛ތᔫဟLjၾზሰ።ᄂቶ੪ތLj
ܘኍᐐଝࡍߛࡁၒ߲࢟ྏ)ݬၒ߲࢟ྏኡᐋ ᒦࡼWTBH
ါDžă
ࡩᔢቃਈࣥဟମด࢟ঢ࢟ഗࡼሆଢ଼)ΔJEPXO*ਜ਼ࡴᄰဟମ
ด࢟ঢ࢟ഗࡼဍ)ΔJ VQ*ߒຳဟLj૾ࡉࡵ࣪ኹ࢛ތă
܈ᒋi! = ΔJVQ0ΔJEPXO ܭာ఼ᒜ౯࢟ঢ࢟ഗጲሰ።ঌ
28
MAX1658/
MAX1659
V+
LDO
DH_
MAX8732A
MAX8733A
MAX8734A
DL_
T1
10μH
1:2.2
T1 = TRANSPOWER TECHNOLOGIES TTI-5870
ᅄ23/! ܤኹẮॺᓐၒ߲
______________________________________________________________________________________
12V
POSITIVE
SECONDARY
OUTPUT
5V
MAIN
OUTPUT
᎖܊࢟۾ฎࡼൈĂ
႐ၒ߲ᓍ࢟Ꮞ఼ᒜ
(5V + 0.1V)
⎛ 0.35μs × 1.5 ⎞
1− ⎜
⎟
2.25μs ⎠
⎝
+ 0.1V − 0.1V = 6.65V
i! = 2ဟǖ
V + (MIN) =
(5V + 0.1V)
⎛ 0.35μs × 1⎞
1− ⎜
⎟
⎝ 2.25μs ⎠
+ 0.1V − 0.1V = 6.04 V
ፐࠥLjW,ܘኍࡍ᎖7/76Wăဣଔ።ᒦ࣪᎖୷܈ಯࡼၒ
߲࢟ྏኡᐋLjၒྜྷ࢟ኹᔢቃᒋ።ᆐ8/6Wă
ಽẮ࢟ঢޘညॺᓐၒ߲
Ᏼ6W4/4W TNQTᒦLjభဧጙৈẮ࢟ঢܤኹࡔᄐ
࢟ঢޘညጙവॺᓐၒ߲)ᅄ23*ăNBY9843B0NBY9844B0
NBY9845Bᎄး᎖ᑚᒬ።Ljፐᆐިဉෝါ༓ᒜ
QXNෝါᏴᓍၒ߲ঌᏲ੪༵ဟถ৫ۣᑺੑࡼঌᏲࢯᑳă
ࠥᅪLjএଝࡼઁᆮኹ࢟വభ᎖খ࿖ঌᏲࢯᑳLjሢᒜၒ
߲࢟ഗă
Ᏼቲᓍၒ߲ଐဟLj።ࡩఠॺᓐ࢟Ꮞࡼൈኊཇă
ჅଐࡼܤኹܘኍᎌးࡼᏫၫ܈ਜ਼࢟ঢLj݀ถ
৫ᆐᓍĂঃၒ߲ᄋჅኊࡼ࢟ഗăᄴݛᑳഗNPTGFUࡼऄ
ࢾൈਜ਼NBY9843B0NBY9844B0NBY9845Bࡼሢഗᒋጐ።
ᔪሤ።ࢯᑳăᎅ᎖ܤኹညݬၫ)ಿྙሣମ࢟ྏĂঃླྀ
ᔝ࢟ᔜਜ਼ധঢ*ࡼ፬ሰLjࢅࡼၒྜྷ.ၒ߲ኹތĂၒ߲ঌᏲ
ࡼࡍތፊਜ਼Ꮻၫ્࣒܈ဧଐጙݛআᏭછăᔏ
ᓍĂঃၒ߲ࡼൈLj݀ᎅࠥࡻࡵࢀࡵᓍၒ߲ࡼ࢟ഗă
ݧᑚৈᔐ࢟ഗཀྵࢾሢഗᒋ)ݬሢഗᒙ Dž
ǖ
I TOTAL = PTOTAL / VOUT
ᒦ J UPUBM ဵࢀࡵᓍၒ߲ࡼ࢟ഗLjQ UPUBM ဵᓍĂঃၒ
߲ࡼᔐၒ߲ൈă
LPRIMARY =
N=
VOUT (VIN(MAX) − VOUT
VIN(MAX) × ƒ × I TOTAL × LIR
VSEC + VFWD
VOUT(MIN) + VRECT
ᒦ M QSJNBSZ ဵᓍ࢟ঢLjO ဵܤኹᏫၫ܈LjW TFD ဵᔢ
ࢅገཇࡼঃླྀᔝᑳഗઁࡼ࢟ኹLjWGXE ဵঃླྀᔝᑳഗࡼ
ᑵሶኹଢ଼LjWPVU)NJO*ဵᓍၒ߲࢟ኹࡼᔢቃᒋLjWSFDU ဵࡴ
ᄰᓨზሆᄴݛᑳഗ NPTGFU ೝ࣡ࡼኹଢ଼ăܤኹঃླྀᔝ
ऩૄ࣡ᄰࡵೌۻޟᓍၒ߲࢟ኹLjऎࡵೌဵݙLjᑚ
ዹభିቃჅኊࡼᏫၫ܈ăᏴࠥ༽ౚሆLjጲଐႯܤኹ
Ꮻၫࡼ܈ါᒦLjገ࠭ঃླྀᔝ࢟ኹᒦିབྷ W PVU! )W TFD .
WPVU*ă
Ắ࢟ঢ።ᒦࡼঃܟऔܘኍถߌ၊71Wጲࡼन૮
࢟ኹLjᑚጙਖࢾࡍࣶၫቆᄂᑳഗ߹Ᏼᅪă໋ᄰਘ
ᑳഗ)ྙ2O5112*ႥࣞვൻLjጐݙးᑚᒬ።ăᑚዹጙ
Ⴅਘᑳഗ)ྙ NVST231*߅ܣ೫ᆎጙኡᐋăᑳ
ഗೝ࣡ࡼन૮࢟ኹᎧ W JO .! W PVU ኹތਜ਼ܤኹᏫၫ܈
ᎌਈǖ
VFLYBACK = VSEC + (VIN - VOUT) ✕ N
ᒦOဵܤኹᏫၫ)܈ঃླྀᔝ0ᓍླྀᔝ*LjWTFD ဵঃླྀᔝᔢ
ࡍᒇഗၒ߲࢟ኹLjWPVU ဵ߱)ᓍ*ၒ߲࢟ኹăྙਫঃླྀᔝ
ऩૄೌᒗ WPVULjऎೌဵݙᒗLjၤါᒦࡼ
WGMZCBDL ።ିབྷWPVUăऔࡼनሶૣࠃ࢟ኹऄࢾᒋથ
ገး።ᎅ᎖ധঢࡼᑩăऔऄࢾ࢟ഗᒗ።ᆐ
ঃླྀᔝၒ߲ᒇഗঌᏲ࢟ഗࡼೝ۶ă
భጲኡᐋጙৈઁኚࡼሣቶᆮኹ࠭ܤኹᑳഗઁࡼᒇ
ഗၒ߲ޘညܘገࡼঌᏲ࢟ഗăሣቶᆮኹ።Ᏼதኹތ
ᄟୈሆᔫLjጲଢ଼ᒗᔢࢅLj݀ᎌੑࡼၒ߲ற
ࣞăၒྜྷਜ਼ၒ߲࢟ྏࡼኡᐋገ൸ᔗሣቶᆮኹĂᆮࢾቶਜ਼
ၾზሰ።ገཇăးࠥಢ።ࡼሣቶᆮኹᒬಢ੪ࣶLj
ᄏดྏሮሣቶᆮኹࡼၫᓾ೯ă
ၒ߲ঌᏲࡼࡍ७ࣞܤછ્፬ሰঌᏲࢯᑳቶถăᄂܰဵࡩ
ঃླྀᔝၒ߲హᏲLjऎᓍླྀᔝၒ߲ᆐ൸ᏲဟLjᎅ᎖ധঢࡼ
ਈᇹLjঃླྀᔝၒ߲࢟ྏభถ્ۻਭߠ࢟Ljဧࡻ࢟ኹᏐ
᎖ଐᒋăᏴᑚᒬ༽ౚሆLjঃླྀᔝၒ߲࣡భถኊገጙৈ
ᔢቃঌᏲਭኹۣઐ࢟വLjጲۣઐೌࡵকၒ߲ࡼჅᎌ
ୈă
______________________________________________________________________________________
29
NBY9843B0NBY9844B0NBY9845B
V + (MIN) =
USE PGND PLANE TO:
USE AGND PLANE TO:
- BYPASS LDO_
- BYPASS VCC AND REF
- TERMINATE EXTERNAL FB
- CONNECT PGND TO THE TOPSIDE STAR GROUND
DIVIDER (IF USED)
OUT5
VIA BETWEEN POWER
- TERMINATE RILIM
AND ANALOG GROUND
(IF USED)
AGND
VIA TO OUT5
- PIN-STRAP CONTROL
INPUTS
PGND
L1
C3
C4
VIA TO OUT3
C1
N4
C2
N3
VIAS TO GROUND
VIA TO LX5
OUT3
N2
D2
ANALOG GROUND
PLANE ON INNER LAYER
VIA TO PGND
GROUND
D1
NBY9843B0NBY9844B0NBY9845B
᎖܊࢟۾ฎࡼൈĂ
႐ၒ߲ᓍ࢟Ꮞ఼ᒜ
L2
N1
V+
VIA TO LX3
CONNECT PGND TO AGND
BENEATH THE CONTROLLER AT NOTE: EXAMPLE SHOWN IS FOR DUAL I.C. n-CHANNEL MOSFET.
ONE POINT ONLY AS SHOWN.
ᅄ24/! QDCݚဣಿ
QDCݚᓰᐌ
றቦࡼQDCݚဵࡻࢅఎਈႼĂࢅᐅĂᆮࢾᔫᓨზ
ࡼਈăᎄࡩࣶৈᓞધᆡ᎖ᄴጙ్QDCဟৎገቃቦLj
॥ᐌ࢟വᒄମ્ሤઑ፬ሰăఎਈൈࡼݚኊገᄂܰ
ᓖፀ)ᅄ24*ăݬNBY2:::ຶৰۇၫᓾ೯ᒦ߲ࡼሮ
ࡼݚဣಿă
ྙᎌభถLj።ჅᎌൈᏄୈहᒙᏴ፝ᒜށࢻࡼۇLj
݀࣡ஜణᏴጙăੑࡼ QDC ݚ።ᔥክጲሆ
ਖᐌǖ
• ።ືࡼށࢻށൈᏄୈᎧށැঢࡼෝผᏄ
ୈಭఎăPVU4 ਜ਼ PVU6 ሆෂݧࣖࡼ QHOE ຳෂ
)߂ᆐ QHOE4 ਜ਼ QHOE6*ăܜ BD ࢟ഗഗྜྷ QHOE4 ਜ਼
QHOE6 ຳෂăྙਫభถࡼજLjஞᏴࢻࠅށ႙ൈ
࢟ഗă
• ᏴൈݧށቩተLjᔢࡍ߈ࣞଢ଼ࢅ PVU4 ਜ਼ PVU6
ᒄମࡼছཷă
• ࡍ࢟ഗᄰവ።భถLjᄂܰဵ࣡ăᑚဵဣሚ
ᆮࢾĂᇄ࣌ࣅᔫࡼਈă
ৎࣶăᑵཀྵࡼ QDC ݚሣገཇමૹ߈ࣞᏴଂॊᒄጙಧ
ඳดLj2nΩࡼሣᔜఝ્ᐆ߅ීመࡼൈႼပă
• DT`! )NBY9843B0NBY9844B*0MY`! )NBY9845B*ਜ਼HOE
Ꭷᄴݛᑳഗࡼೌ።ݧLfmwjoঢ።ೌऱါLjᑚዹ
భཀྵۣሢഗࡼறࣞăݧ 9 ୭ TP! NPTGFU ဟLjᔢੑ
ᄰਭࢻݚށሣ࠭ᅪݾൈၒ႙ࡵ NPTGFULjऎᏴ
NPTGFU ด)ݾሆݚ*ݝDT`0MY`ೌሣă
• ܘኍᏴᔓሣࣞޠऱෂᎌჅᅟဟLj።၅ኡዓ࢟ޠঢߠ࢟
ᄰവࡼࣞޠLjऎݙገዓޠह࢟ᄰവࡼࣞޠăಿྙLjุ
భᐐଝၒྜྷ࢟ྏࡵ ܟNPTGFU ࡼ௦ಭLjጐݙገᐐࡍ
࢟ঢࡵᄴݛᑳഗ࢟ঢࡵၒ߲݆࢟ྏᒄମࡼ௦ಭă
• ཀྵۣ PVU`ᎧDPVU` ࡼೌሣ༦ᒇăऎLjᏴ෭ቋ༽ౚ
ሆLjభጲᎌፀᐐଝPVU`ೌ࢛ਜ਼ၒ߲݆࢟ྏᒄମࡼ
ݚሣݬ)ࣞޠᆮࢾቶఠ ݝॊ*ă
• Ⴅఎਈஂ࢛)CTU`ĂMY`ĂEI`ਜ਼EM`*።Ꮠಭැঢࡼ
ෝผཌᎮ)SFGĂJMJN`ਜ਼GC`*ăݧQHOE4ਜ਼QHOE6
ᔫᆐ FNJ ືLjဧ६ఎਈᐅဉᏐಭ JD ࡼनౣॊኹ
ਜ਼ෝผവ࢟ྏă
• ࢟Ꮞሣਜ਼ঌᏲೌሣ።భถăᑚဵဣሚൈࡼਈ
ăݧᄵQDC! )3p{Ꭷ2p{*భဧ൸Ᏺൈᄋ2%
30
______________________________________________________________________________________
᎖܊࢟۾ฎࡼൈĂ
႐ၒ߲ᓍ࢟Ꮞ఼ᒜ
ݚݛᒾ
2* ၅ሌहᒙൈᏄୈLj݀࣡)O30O5ᏎĂDJO`Ă
D PVU` ਜ਼ E2 ዴ*ஜچᏴጙăྙᎌభถLjჅᎌᑚ
ቋᏄୈࡼೌሣ࣒हᏴࢻށLjݧࡍෂ૩ᄵቲೌă
3* ఼ᒜJD።ణதᄴݛᑳഗNPTGFUहᒙLjᔢੑहᏴ
࢟വࡼۇ۳ෂLjጲۣᑺEI`ĂHOEਜ਼EM`ᐜདࣅሣ
ऎăEM`ᐜݚሣܘኍऎLjྙਫNPTGFUᎧ
఼ᒜJDࡼ௦ಭᆐ2፞ࡁLjሣ።ᆐ61njmᒗ211njmă
4* ჅᎌᐜདࣅᏄୈ)CTU`औਜ਼࢟ྏĂW,വ࢟ྏ*
ణத఼ᒜૹᒦहᒙă
5* ED.ED఼ᒜࡼऱါྙሆǖᏴୈএதݚጙ్
ቃෂ૩ࡼෝผຳෂăᑚጙቃ్ෝผຳෂೌᒗ
HOE! )ᅄ24*Lj݀ڳᔪᆐSFGਜ਼WDD വ࢟ྏĂGCॊ
ኹጲૺ JMJN࢟ᔜ)ྙਫᎌ*ࡼށăݚጙ్ቃ
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୭এதBHOEਜ਼QHOEೌᏴጙă
6* Ᏼ࢟വ)ށࢻۇൈݚ*ށጙ్ቩተLjጲିܣቃೝ
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ᑳഗᏎᒄମࡼ࢟ᔜ።ቃăݧ༦ࡼೌሣ
ࢻށቩተ)᎖ NPTGFUĂၒྜྷਜ਼ၒ߲࢟ྏࡼ
*ᒗቃቯࡲ)ᔢੑᒑᄰਭጙৈਭೌ*ă
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NBY2:::ຶৰۇဣಿ*ᔫᆐFNJື)༓ೲᅎୀ*ăᑚ
ቋॊܰࣖೂೌᒗቩተਭLjকਭೌࢻ
ށਜ਼QHOEށăᏴୈሆऱݚᅪጙৈဣށLjጲ
ᔫᆐືLjဣށጐೌᒗቩተਭă
7* ၒ߲࢟Ꮞ)ށW DPSF ਜ਼ᇹᄻຳෂ*።ᄰਭࣶৈਭᒇ
ೌᒗၒ߲݆࢟ྏࡼᑵĂঌă
ܭ6/! NBY9843B0NBY9844B0NBY9845Bਜ਼NBY28880NBY2:880NBY2:::ࡼཌܰ
MAX8732A/MAX8733A/MAX8734A
MAX1777/MAX1977/MAX1999
Line Transient Behavior
Improved line transient behavior requires only
a 0.1μF filter capacitor on V+. Allows fast
rising-edge line transients of 10V/μs and
falling-edge line transients of 5V/μs.
A 4Ω/4.7μF filter capacitor is required on V+ to
limit the dV/dt on the V+ pin.
Ultrasonic Mode
Simplified Z pattern offers better efficiency
and smoother transition into continuousconduction mode.
Original “W” pattern conducts through the highside MOSFET’s body diode, reducing efficiency.
Transition between ultrasonic mode and
continuous-conduction mode is not as smooth.
LDO3 and LDO5 Sequencing
LDO3 starts only after LDO5 is in regulation,
reducing the inrush current when SHDN goes
high.
LDO3 and LDO5 start up together at the current
limit of each LDO, causing large inrush currents
through the 4Ω series resistor at V+.
Soft-Shutdown Enable Delay
Soft-shutdown (10Ω discharge feature) is
enabled immediately when an output is
enabled, and is not dependent on the 22ms
(typ) startup undervoltage blanking timer.
Soft-shutdown (10Ω discharge feature) is
enabled only after the 22ms (typ) startup
undervoltage blanking time. This causes DL_ to
be driven high if the part is commanded to turn
off before the 22ms timer.
High-Output Impedance in UVLO
When LDO5 falls below its 4V (typ) UVLO
threshold, DH_ and DL_ are immediately
pulled low, and the outputs are high
impedance. The outputs are discharged by
the load.
When LDO5 falls below its 4V (typ) UVLO
threshold, DH_ is immediately pulled low and
DL_ forced high to clamp the output rails. This
causes the outputs to swing below ground.
______________________________________________________________________________________
31
NBY9843B0NBY9844B0NBY9845B
• Ⴥᎌ఼ᒜ୭)SKIPĂJMJN`ࢀ*ೌᒗୈࡼHOE
WDDă
NBY9843B0NBY9844B0NBY9845B
᎖܊࢟۾ฎࡼൈĂ
႐ၒ߲ᓍ࢟Ꮞ఼ᒜ
```````````````````````````` ࢾ৪ቧᇦ)ኚ*
PART
PINTEMP RANGE
PACKAGE
MAX8734AEEI+ -40°C to +85°C 28 QSOP
MAX8734AEEI
+ ܭာᇄॖᓤă
-40°C to +85°C 28 QSOP
5V/3V
SWITCHING
FREQUENCY
(kHz)
200/300 or
400/500
400kHz/500
```````````````````````````` ୭ᒙ)ኚ*
TOP VIEW
CS3 1
28 BST3
PGOOD 2
27 LX3
ON3 3
26 DH3
ON5 4
25 LDO3
ILIM3 5
SHDN 6
24 DL3
MAX8732A
MAX8733A
23 GND
FB3 7
22 OUT3
REF 8
21 OUT5
FB5 9
20 V+
PRO 10
19 DL5
ILIM5 11
18 LDO5
SKIP 12
17 VCC
CS5 13
16 DH5
BST5 14
15 LX5
QSOP
```````````````````````````````````````` በຢቧᇦ
TRANSISTOR COUNT: 8335
PROCESS: BiCMOS
32
______________________________________________________________________________________
᎖܊࢟۾ฎࡼൈĂ
႐ၒ߲ᓍ࢟Ꮞ఼ᒜ
QSOP.EPS
PACKAGE OUTLINE, QSOP .150", .025" LEAD PITCH
21-0055
E
1
1
NBYJN ۱யࠀူێ
۱ய 9439ቧረ ᎆᑶܠ൩ 211194
ॅ࢟જǖ911!921!1421
࢟જǖ121.7322 62::
ࠅᑞǖ121.7322 63::
Nbyjn࣪ݙNbyjnޘອጲᅪࡼྀੜ࢟വဧঌᐊLjጐݙᄋᓜಽభăNbyjnۣഔᏴྀੜဟମĂᎌྀੜᄰۨࡼ༄ᄋሆኀখޘອᓾ೯ਜ਼ਖৃࡼཚಽă
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 (408) 737-7600 ___________________33
© 2005 Maxim Integrated Products
Printed USA
ဵ Nbyjn!Joufhsbufe!Qspevdut-!Jod/ ࡼᓖݿܪă
NBY9843B0NBY9844B0NBY9845B
````````````````````````````````````````````````````````````````````````````ॖᓤቧᇦ
(۾ၫᓾ೯ᄋࡼॖᓤᅄభถဵݙᔢதࡼਖৃLjྙኊᔢதࡼॖᓤᅪቯቧᇦLj༿އኯ www.maxim-ic.com.cn/packagesă)