NJU7677 Data Sheet

NJU7677
1.8V Operate PWM control Step-Up / Flyback switching regulator IC
■ GENERAL DESCRIPTION
■ PACKAGE OUTLINE
The NJU7677 is a high-speed switching regulator control IC for
PWM control step-up and fly-back converter that operates from
1.8V. It incorporates a totem pole driver output, which can directly
drive an external MOS-FET. The NJU7677 also has a soft-start
function, dead time control and timer latch for short circuit protection
and their times are all adjustable with external parts. It is available in
a small and thin 8-lead MSOP (TVSP) package. It is suitable for
battery powered applications.
NJU7677RB1
(MSOP8 (TVSP8))
■ FEATURES
● PWM switching control
● Operating Voltage
1.8V to 7V
● Wide Oscillator Range 300kHz to 1MHz
● Maximum Duty Cycle
90% typ.
● Quiescent Current
600µA typ.
● Soft-Start Function
Internal : 4ms typ. or adjustable
● Dead Time Control
● Timer Latch for Short Circuit Protection
● C-MOS Technology
● Package Outline
NJU7677RB1 : MSOP8 (TVSP8)*
*MEET JEDEC MO-187-DA / THIN TYPE
■ PIN CONFIGURATION
1
8
2
7
3
6
4
5
NJU7677RB1
Ver.2012-08-03
PIN FUNCTION
1. V+
2. FB
3. IN4. SCP
5. DTC
6. RT
7. GND
8. OUT
-1-
NJU7677
■ BLOCK DIAGRAM
+
V
FB
0.65V
ER⋅AMP
IN1V
0.15V
Vref
Soft Start
UVLO
Latch
PWM
Buffer
2µA
SCP
OUT
SCP
OSC
2kΩ
0.5V
0.5
1V
RT
0.6V
A
1V
DTC
RT
GND
RT
-2-
Ver.2012-08-03
NJU7677
■ ABSOLUTE MAXIMUM RATINGS
PARAMETER
SYMBOL
Supply Voltage
V+
Output Pin Current
IO
Power Dissipation
PD
Operating Temperature Range
TOPR
Storage Temperature Range
TSTG
MAXIMUM RATINGS
+8
±50
320
-40 to +85
-40 to +125
■ RECOMMENDED OPERATING CONDITIONS
PARAMETER
SYMBOL
MIN.
Operating Voltage
V+
1.8
Oscillator Timing Resistor
RT
30
Oscillation Frequency
fOSC
300
TYP.
–
47
700
Under Voltage Lockout Block
ON Threshold Voltage
OFF Threshold Voltage
Hysteresis Voltage
Soft Start Block
Soft Start Time
Short Circuit Protection Block
Input Threshold Voltage
Charge Current
Latch Mode
ON Threshold Voltage
Latch Mode
OFF Threshold Voltage
Oscillator Block
RT Pin Voltage
Oscillation Frequency
Oscillate Supply Voltage
Fluctuations
Oscillate Temperature
Fluctuations
Ver.2012-08-03
MAX.
7
120
1,000
(Ta=25°C)
UNIT
V
kΩ
kHz
(V+=3.3V, RT=47kΩ, Ta=25°C)
■ ELECTRICAL CHARACTERISTICS
PARAMETER
(Ta=25°C)
UNIT
V
mA
mW
°C
°C
SYMBOL
VT_ON
VT_OFF
VHYS
TSS
TEST CONDITION
V+= L → H
V+= H → L
VT_ON → Duty=80%
MIN.
TYP.
MAX.
UNIT
1.6
1.5
60
1.7
1.6
100
1.8
1.7
–
V
V
mV
2
4
8
ms
VT_PC
ICHG
FB Pin
VSCP=0V
0.95
1.5
1.00
2
1.05
2.5
V
µA
VT_LA
SCP Pin
0.90
1.00
1.10
V
VT_LAOFF
SCP Pin
0.35
0.6
0.85
V
-8%
630
0.5
700
+8%
770
V
kHz
VRT
fOSC
fDV
V+=1.8V to 7V
–
1
–
%
fDT
Ta=-40°C to +85°C
–
3
–
%
-3-
NJU7677
(V+=3.3V, RT=47kΩ, Ta=25°C)
■ ELECTRICAL CHARACTERISTICS
PARAMETER
Error Amplifier Block
Reference Voltage
Input Bias Current
Open Loop Gain
Gain Bandwidth Product
Output Source Current
Output Sink Current
SYMBOL
VB
IB
AV
GB
IOM+
IOM-
TEST CONDITION
MIN.
TYP.
MAX.
UNIT
-1.0%
-0.1
–
–
20
1.0
1.00
–
80
1
35
4.0
+1.0%
0.1
–
–
50
12
V
µA
dB
MHz
µA
mA
0.10
0.36
85
45
0.16
0.42
90
55
0.22
0.48
95
65
V
V
%
%
IO=-20mA
IO=-20mA, V+=1.8V
IO=+20mA
IO=+20mA, V+=1.8V
–
–
–
–
6
10
4.5
8
12
20
9
16
Ω
Ω
Ω
Ω
RL=Non Load
–
600
900
µA
VFB=1V, VIN-=0.9V
VFB=1V, VIN-=1.1V
PWM Comparate Block
Input Threshold Voltage
Maximum Duty Cycle
Output Block
Output High Level
ON Resistance
Output Low Level
ON Resistance
General Characteristics
Quiescent Current
-4-
VT_0
VT_50
MAXDUTY_1
MAXDUTY_2
ROH
ROH_1.8
ROL
ROL_1.8
IDD
Duty=0%
Duty=50%
VFB=0.9V
VFB=0.9V, RDTC=43kΩ
Ver.2012-08-03
NJU7677
■ TYPICAL APPLICATIONS
Step-Up Converter
SBD
L
V
+
VOUT
CIN
R2
NJU7677
C
+
1
V
OUT
8
2
FB
GND
7
3
IN-
RT
6
4
SCP
DTC
5
CNF
COUT
FET
R1
RT
RNF
CSCP
CS
RDTC
Flyback Converter
V
T
+
SBD
VOUT
CIN
NJU7677
C
CNF
RNF
1
V
2
+
FET
OUT
8
FB
GND
7
3
IN-
RT
6
4
SCP
DTC
5
COUT
R1
RT
CSCP
Ver.2012-08-03
R2
RDTC
CS
-5-
NJU7677
■ TYPICAL CHARACTERISTICS
Oscillation Frequency vs. Timing Resistance
+
(V =3.3V, Ta=25 C)
90
AX
UTY_1
95
100
10
85
80
100
100
Timing Resistance R (kΩ)
OSC
o
80
(%)
UTY
60
AX
700
680
660
(V+=3.3V, RT=47kΩ, Ta=25 C)
100
T
Duty Cycle M D
Oscillation Frequency fosc (kHz)
o
(R =47kΩ, Ta=25 C)
720
0
2
4
6
Operating Voltage V+ (V)
8
40
20
0
0
20
40
60
80
Dead Time Control Resistance R
DTC
Reference Voltage vs. Operating Voltage
T
(µA)
L
1000
DD
1.005
1
0.995
0.99
(R =47kΩ, R =Non Load, Ta=25 C)
1200
Quiescent Current I
B
o
(Ta=25 C)
1.01
100
(kΩ)
Quiescent Current vs. Operating Voltage
o
Reference Voltage V (V)
(kHz)
Duty Cycle vs. RDTC
Oscillation Frequency vs. Operating Voltage
740
1000
Oscillator Frequency f
T
-6-
o
(V =3.3V, Ta=25 C)
100
Maximum Duty Cycle
M D
(%)
1000
Oscillation Frequency f
Maximum Duty Cycle vs. Oscillator Frequency
o
OSC
(kHz)
+
0
2
4
6
Operating Voltage V+ (V)
8
800
600
400
200
0
0
2
4
6
Operating Voltage V+ (V)
8
Ver.2012-08-03
NJU7677
■ TYPICAL CHARACTERISTICS
Error Amplifier Block
Voltage Gain, Phase vs. Frequency
(V+=3.3V, Gain=40dB, Ta=25 oC)
Output High Level ON Resistance
ROH (Ω)
135
Phase
Gain
30
90
15
45
0
0.1
20
180
1
10
100
1000
Frequency f (kHz)
Output Block
Output High Level ON Resistance
vs. Temperature (Io=-20mA)
16
Phase Φ (deg)
45
Output Low Level ON Resistance
ROL (Ω)
Voltage Gain Av (dB)
60
0
10000
Output Block
Output Low Level ON Resistance
vs. Temperature (Io=+20mA)
14
12
15
V+=1.8V
10
V+=3.3V
5
+
V =7V
0
-50
Ver.2012-08-03
-25
0
25 50 75 100 125
Ambient Temperature Ta (oC)
V+=1.8V
10
8
6
V+=3.3V
4
2
0
-50
V+=7V
-25
0
25 50 75 100 125
Ambient Temperature Ta (oC)
-7-
NJU7677
■ TYPICAL CHARACTERISTICS
Soft Start Time vs. Temperature
Reference Voltage vs. Temperature
+
+
1.005
B
7
(V =3.3V)
1.01
Reference Voltage V (V)
Soft Start Time Tss (ms)
8
(V =3.3V)
6
5
4
3
2
-50
1
0.995
0.99
-50
-25
0
25 50 75 100 125
Ambient Temperature Ta (oC)
-25
0
25 50 75 100 125
Ambient Temperature Ta (oC)
Muximum Duty Cycle vs. Temperature
Oscillator Frequency vs. Temperature
+
760
Threshold Voltage (V)
Muximum Duty Cycle
(%)
M D
680
660
1.7
MAXDUTY_1
70
V
T_ON
VT_OFF
-25
0
25 50 75 100 125
Ambient Temperature Ta (oC)
60
MAXDUTY_2
50
-25
0
25 50 75 100 125
Ambient Temperature Ta (oC)
Quiescent Current vs. Temperature
Under Voltage Lockout Block
vs. Temperature
1.6
1.5
-50
80
40
-50
-25
0
25 50 75 100 125
Ambient Temperature Ta (oC)
1.65
1.55
90
AX
700
1.75
(V =3.3V)
UTY
720
640
-50
100
T
740
1.8
-8-
(V =3.3V, R =47kΩ)
1000
Quiescent Current IDD (µA)
Oscillator Frequency fOSC (kHz)
+
(V+=3.3V, R =47kΩ)
T
800
600
400
200
0
-50
-25
0
25 50 75 100 125
Ambient Temperature Ta (oC)
Ver.2012-08-03
NJU7677
MEMO
[CAUTION]
The specifications on this databook are only
given for information , without any guarantee
as regards either mistakes or omissions. The
application circuits in this databook are
described only to show representative usages
of the product and not intended for the
guarantee or permission of any right including
the industrial rights.
Ver.2012-08-03
-9-