GC3-K020B Page 1
APPLICATION MANUAL
Negative-input Negative-output Regulator IC
TK721xxCS
CONTENTS
1 . DESCRIPTION 2
2 . FEATURES 2
3 . APPLICATIONS 2
4 . PIN CONFIGURATION 2
5 . PACKAGE OUTLINE 2
5. ORDERING INFORMATION 3
6 . BLOCK DIAGRAM 4
7 . ABSOLUTE MAXIMUM RATINGS 4
8 . ELECTRICAL CHARACTERISTICS 5
9 . TEST CIRCUIT 6
10 . TYPICAL CHARACTERISTICS 7
11 . PIN DESCRIPTION 22
12 . APPLICATIONS INFORMATION 23
12-2. ESR Stability 24
12-3. 25
Operating Region and Power Dissipation 25
12-4 Application hint 27
13 . NOTES 28
14. OFFICES 28
TK721xxCS
GC3-K020B Page 2
Negative-input Negative-output Regulator IC
TK721xxCS
1. DESCRIPTION
TK721xxCS series is a negative-input negative-output
regulator IC using silicon monolithic bipolar structure
which can supply 150mA output current.
The output voltage can be set from -2.0 to -9.5V, which is
trimmed in high accuracy.
TK721xxCS is supplied with ON/OFF terminal and noise
reduction terminal. The ON/OFF control can be
controlled directly with positive logic or CPU.
Moreover, TK721xxCS is provided with short-circuit
protection and thermal shutdown.
2. FEATURES
! High Output Voltage Accuracy(±2.0% or ±60 mV)
! ON/OFF control available (High OFF)
! Built-in short-circuit protection and thermal shutdown.
! Guarantee 150mA output current(200mA peak)
! Ceramic capacitor available for application
3. APPLICATIONS
! Battery Powered Systems
! DSC, CCD bias, GaAs bias.
4. PIN CONFIGURATION
Top View
1
3
2
5
4
VEE
Vout
Np GND
Cont
5. PACKAGE OUTLINE
! SOT23-5
2.9
1.6
1.1
0.15
0.4
2.8
2.4
Reference Mount Pad
1.0
0.7
(0.3)
0 ~0.1 ±0.1
1.3max
0.1
±0.2
Mark
±0.2
±0.2
54
13
+0.10
−0.05
+0.10
−
0.05
0.95 0.95
0.95 0.95
M
0.1
TK721xxCS
GC3-K020B Page 3
5. ORDERING INFORMATION
Package Vout Part Number Marking
-2.0 TK72120CS K20
-2.5 TK72125CS K25
-3.0 TK72130CS K30
-3.5 TK72135CS K35
-4.0 TK72140CS K40
-4.5 TK72145CS K45
-5.0 TK72150CS K50
-5.5 TK72155CS K55
-6.0 TK72160CS K60
-6.5 TK72165CS K65
-7.0 TK72170CS K70
-7.5 TK72175CS K75
-8.0 TK72180CS K80
-8.5 TK72185CS K85
-9.0 TK72190CS K90
-9.5 TK72195CS K95
SOT23-5
For other voltages, please contact the TOKO sales office.
TK721xxCS
GC3-K020B Page 4
6. BLOCK DIAGR AM
Bandgap
Reference
Over Heat &
Over Current
Protection
VEE
Np
Vout
90k
Cont
GND
Control:Low Level On
7. ABSOLUTE MAXIMUM RATINGS
Ta=25°C
Parameter Symbol Rating Units Conditions
Supply Voltage Vin -20 V |Vin|+|Vcont|≤20V
Control pin Voltage Vcont -0.4 ~ +5 V |Vin|+|Vcont|≤19V
Power Dissipation
(SOT23-5 Simple substance) PD500 mW PD must be decreased at the rate of 4mW/°C
for operation above 25°C.
Storage Temperature Range Tstg -55 ~ +150 °C
Operating Temperature Range TOP -40 ~ 85 °C
Operating Voltage Range VOP -19 V |Vin|+|Vcont|≤19V
Output short-circuit current Ishort 300 mA Over Current Protection
Absolute maximum ratings are limits beyond which damage to the device may occur.
When the operation exceeds this standard, quality can not be guaranteed.
TK721xxCS
GC3-K020B Page 5
8. ELECTRICAL CHARACTERISTICS
Vin=VoutTYP-1.5V, Ta=25°C
Value
Parameter Symbol MIN TYP MAX Unit Condition
Vout Vout Refer to TABLE 1 V Iout=5mA
Line Regulation LinReg 1 5 mV ∆Vin=5V
Refer to TABLE 1 mV Iout=5mA~50mA
Refer to TABLE 1 mV Iout=5mA~100mA
Load Regulation LoaReg
Refer to TABLE 1 mV Iout=5mA~150mA
0.29 0.50 V Iout=50mA
0.48 0.80 V Iout=100mA
Dropout Voltage *1 Vdrop
0.66 1.10 V Iout=150mA
Supply Current Icc 155 250 µA Iout=0mA
Standby Current Istandby 20 60 µA Vout Off State
Peak Output Current IoutPEAK 200 280 mA When Vout drops 10%
Control Current Icont 12 30 µAVcont=+1.8V
0 0.3 V Vout ON State
Control Voltage Vcont 1.5 V Vout OFF State
*1 For Vout≥-3.0 no regulations
TABLE 1
LoaReg
Vout Iout=50mA Iout=100mA Iout=150mA
Part Number
MIN TYP MAX TYP MAX TYP MAX TYP MAX
TK72120CS -2.060 -2.000 -1.940 9 24 15 39 24 60
TK72125CS -2.560 -2.500 -2.440 9 24 15 39 24 60
TK72130CS -3.060 -3.000 -2.940 9 24 15 39 24 60
TK72135CS -3.570 -3.500 -3.430 11 28 18 46 28 70
TK72140CS -4.080 -4.000 -3.920 12 30 20 52 32 80
TK72145CS -4.590 -4.500 -4.410 14 34 23 59 36 90
TK72150CS -5.100 -5.000 -4.900 15 38 25 65 40 100
TK72155CS -5.610 -5.500 -5.390 17 41 28 72 44 110
TK72160CS -6.120 -6.000 -5.880 18 45 30 78 48 120
TK72165CS -6.630 -6.500 -6.370 20 49 33 85 52 130
TK72170CS -7.140 -7.000 -6.860 21 53 35 91 56 140
TK72175CS -7.650 -7.500 -7.350 23 56 38 98 60 150
TK72180CS -8.160 -8.000 -7.840 24 60 40 104 64 160
TK72185CS -8.670 -8.500 -8.330 26 64 43 111 68 170
TK72190CS -9.180 -9.000 -8.820 27 68 45 117 72 180
TK72195CS -9.690 -9.500 -9.310 29 71 48 124 76 190
TK721xxCS
GC3-K020B Page 6
9. TEST CIRCUIT
! DC ! Load Transient
Icont
Vcont
0.01
µ
Ｆ
1
µ
Ｆ
VinCin
Vout Cout
Cnp
1
3
2
5
4
VEE
Vout
Np GND
Cont
Iout
VA
1
µ
Ｆ
A
Iin
VinCin
Vout Cout
Cnp
1
3
2
5
4
VEE
Vout
Np GND
Cont
Iout
V
! Line Transient ! ON/OFF Transient
Cin
Vout Cout
Cnp
1
3
2
5
4
VEE
Vout
Np GND
Cont
Iout
V
↑
Vin=Vouttyp-2.5V
Vin=Vouttyp-1.5V
↓
Vin
VinCin Vout Cout
Cnp
Vcont=0→1.5→0
1
3
2
5
4
VEE
Vout
Np GND
Cont
Iout
V
! Ripple Rejection ! ESR Stability
View point
Cout
Cnp
1
3
2
5
4
VEE
Vout
Np GND
Cont
Iout
Vripple=500mVp-p
Vin=Vouttyp-2.0V
VinCin
Vout
Cout
Cnp
1
3
2
5
4
VEE
Vout
Np GND
Cont
Iout
V
ESR
TK721xxCS
GC3-K020B Page 7
10. TYPICAL CHARACTERISTICS
10-1 DC CHARACTERISTICS
Unless otherwise specified Vin=VoutTYP-1.5V,Vcont=0V,Cin=1.0uF(MLCC),Cout=1.0uF(MLCC),Cnp=0.01uF
Ta=25°C
Icont
Vcont
0.01
µ
Ｆ
1
µ
Ｆ
VinCin
Vout Cout
Cnp
1
3
2
5
4
VEE
Vout
Np GND
Cont
Iout
VA
1
µ
Ｆ
A
Iin
! Line Regulation ! Load Regulation
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
10.0
0 5 10 15 20
Vin (-V)
Vout (-V)
0
10
20
30
40
50
60
70
80
90
100
050100150
Iout (mA)
ΔVout (mV)
! IoutPEAK ! IQ
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
10.0
0 100 200 300 400
Iout (mA)
Vout (-V)
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
0 100 200 300 400
Iout (mA)
IQ (mA)
Vout=-8.5V
Vout=-5.0V
Vout=-2.5V
Vout=-8.5/-5.0/-2.5V
Vout=-8.5V
Vout=-5.0V
Vout=-2.5V
TK721xxCS
GC3-K020B Page 8
Unless otherwise specified Vin=VoutTYP-1.5V,Vcont=0V,Cin=1.0uF(MLCC),Cout=1.0uF(MLCC),Cnp=0.01uF
Ta=25°C
! Iin (Iout=0mA) ! Dropout Voltage
0
200
400
600
800
1000
1200
1400
1600
1800
2000
0 5 10 15 20
Vin (-V)
Iin (uA)
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
050100150
Iout (mA)
Vdrop (V)
! Vout VS Vcont ! Vout VS VIN
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
10.0
0.0 0.5 1.0 1.5 2.0
Vcont (V)
Vout (-V)
-0.5
-0.4
-0.3
-0.2
-0.1
0
0.1
0.2
0.3
0.4
0.5
-0.5 0 0.5 1
ΔVIN (-V)
ΔVout (-V)
! Icont VS Vcont (Iout=1mA) ! Icc Off Mode (Vcont=1.5V,Iout=0mA)
-50
-40
-30
-20
-10
0
10
20
30
40
50
-1.0 0.0 1.0 2.0 3.0 4.0 5.0
Vcont (V)
Icont (uA)
0
10
20
30
40
50
60
70
80
90
100
0 5 10 15 20
Vin (-V)
Iin (uA)
Vout=-8.5V
Vout=-5.0V
Vout=-2.5V
Vout=-8.5V
Vout=-5.0V
Vout=-2.5V
Iout=0/30/60/90/120/150mA
TK721xxCS
GC3-K020B Page 9
10-2 Temperature characteristic
Unless otherwise specified Vin=-VoutTYP-1.5V,Vcont=0V,Cin=1.0uF(MLCC),Cout=1.0uF(MLCC),Cnp=0.01uF
Icont
Vcont
0.01
µ
Ｆ
1
µ
Ｆ
VinCin
Vout Cout
Cnp
1
3
2
5
4
VEE
Vout
Np GND
Cont
Iout
VA
1
µ
Ｆ
A
Iin
! TK72125CS Vout ! TK72185CS Vout
2.400
2.420
2.440
2.460
2.480
2.500
-40 -20 0 20 40 60 80 100
Ta (℃)
Vout (-V)
8.450
8.470
8.490
8.510
8.530
8.550
-40 -20 0 20 40 60 80 100
Ta (℃)
Vout (-V)
! TK72125CS IoutPEAK ! TK72185CS IoutPEAK
250
260
270
280
290
300
310
320
330
340
350
-40 -20 0 20 40 60 80 100
Ta (℃)
Iout_MAX
250
260
270
280
290
300
310
320
330
340
350
-40 -20 0 20 40 60 80 100
Ta (℃)
Iout_MAX
TK721xxCS
GC3-K020B Page 10
Unless otherwise specified Vin=-VoutTYP-1.5V,Vcont=0V,Cin=1.0uF(MLCC),Cout=1.0uF(MLCC),Cnp=0.01uF
! TK72125CS LoadReg ! TK72185CS LoadReg
0
20
40
60
80
100
120
140
160
-40 -20 0 20 40 60 80 100
Ta (℃)
LoadReg (mV)
0
20
40
60
80
100
120
140
160
-40 -20 0 20 40 60 80 100
Ta (℃)
LoadReg (mV)
! TK72125CS ON/OFF ! TK72185CS ON/OFF
0.5
0.6
0.7
0.8
0.9
1.0
1.1
1.2
1.3
1.4
1.5
-40 -20 0 20 40 60 80 100
Ta (℃)
Vcont (V)
0.5
0.6
0.7
0.8
0.9
1.0
1.1
1.2
1.3
1.4
1.5
-40 -20 0 20 40 60 80 100
Ta (℃)
Vcont (V)
! TK72125CS Iin(Iout=0mA) ! TK72185CS Iin(Iout=0mA)
100
110
120
130
140
150
160
170
180
190
200
-40 -20 0 20 40 60 80 100
Ta (℃)
Icc (uA)
100
110
120
130
140
150
160
170
180
190
200
-40 -20 0 20 40 60 80 100
Ta (℃)
Icc (uA)
Io=5-150mA
Io=5-100mA
Io=5-150mA
Io=5-100mA
Vout Off
Vout Off
Vout On Vout On
TK721xxCS
GC3-K020B Page 11
Unless otherwise specified Vin=-VoutTYP-1.5V,Vcont=0V,Cin=1.0uF(MLCC),Cout=1.0uF(MLCC),Cnp=0.01uF
! TK72125CS Icont ! TK72185CS Icont
0
2
4
6
8
10
12
14
16
18
20
-40 -20 0 20 40 60 80 100
Ta (℃)
Icont_1.8V (uA)
0
2
4
6
8
10
12
14
16
18
20
-40 -20 0 20 40 60 80 100
Ta (℃)
Icont_1.8V (uA)
! TK72125CS Icc_OFFMode ! TK72185CS Icc_OFFMode
0
5
10
15
20
25
30
35
40
45
50
-40 -20 0 20 40 60 80 100
Ta (℃)
Icc_OffMODE (uA)
0
5
10
15
20
25
30
35
40
45
50
-40 -20 0 20 40 60 80 100
Ta (℃)
Icc_OffMODE (uA)
! TK72125CS Vdrop ! TK72185CS Vdrop
For Vout≥-2.0V, no regulations
0
100
200
300
400
500
600
700
800
900
-40 -20 0 20 40 60 80 100
Ta (℃)
Vdrop (mV)
Io=50/100/150mA
TK721xxCS
GC3-K020B Page 12
10-3 Load Transient
Unless otherwise specified Vin=VoutTYP-1.5V,Cin=1.0uF(MLCC),Cnp=0.01uF
VinCin
Vout Cout
Cnp
1
3
2
5
4
VEE
Vout
Np GND
Cont
Iout
V
!TK72125CS
Vout:200mV/div Time:200usec/div
!TK72185CS
Vout:200mV/div Time:200usec/div
!TK72125CS
Vout:200mV/div Time:200usec/div
!TK72185CS
Vout:200mV/div Time:200usec/div
Vout
Iout Iout
Vout
Cout=2.2uF(Tantalum)
Cout=1.0uF(Tantalum) Cout=1.0uF(Tantalum)
Cout=2.2uF(Tantalum)
5mA 100mA 100mA
5mA
Iout
Vout
Iout
5mA 100mA
Cout=1.0uF(MLCC)
Cout=2.2uF(MLCC)
Cout=1.0uF(MLCC)
Cout=2.2uF(MLCC)
5mA 100mA
Vout
TK721xxCS
GC3-K020B Page 13
Unless otherwise specified Vin=VoutTYP-1.5V,Cin=1.0uF(MLCC),Cnp=0.01uF
!TK72125CS
Vout:1V/div Time:10usec/div
!TK72185CS
Vout:2V/div Time:10usec/div
!TK72125CS
Vout:500mV/div Time:4msec/div
!TK72185CS
Vout:500mV/div Time:4msec/div
Vout
Iout 0mA
100mA
Cout=1.0uF(MLCC)
Cout=2.2uF(MLCC)
Vout
Iout 0mA
100mA
Cout=1.0uF(MLCC)
Cout=2.2uF(MLCC)
Vout
Iout Iout
Vout
0mA
100mA 100mA
0mA
Cout=0.1uF(MLCC)
Cout=1.0uF(MLCC)
Cout=2.2uF(MLCC)
Cout=0.1uF(MLCC)
Cout=1.0uF(MLCC)
Cout=2.2uF(MLCC)
TK721xxCS
GC3-K020B Page 14
Unless otherwise specified Vin=VoutTYP-1.5V,Cin=1.0uF(MLCC),Cnp=0.01uF
!TK72125CS
Vout:500mV/div Time:10usec/div
!TK72185CS
Vout:500mV/div Time:10usec/div
!TK72125CS
Vout:100mV/div Time:4msec/div
!TK72185CS
Vout:100mV/div Time:4msec/div
Cout=1.0uF(Tantalum)
Cout=2.2uF(Tantalum)
Vout
Iout 0mA
100mA
Vout
Iout
100mA
0mA
Cout=1.0uF(Tantalum)
Cout=2.2uF(Tantalum)
Cout=1.0uF(Tantalum)
Cout=2.2uF(Tantalum)
Vout
Iout 100mA
0mA
Vout
Iout 0mA
100mA
Cout=1.0uF(Tantalum)
Cout=2.2uF(Tantalum)
TK721xxCS
GC3-K020B Page 15
10-4 ON/OFF Transient
Vin=VoutTYP-1.5V,Cin=1.0uF(MLCC),Iout=100mA
VinCin Vout Cout
Cnp
Vcont=0→1.5→0
1
3
2
5
4
VEE
Vout
Np GND
Cont
Iout
V
!TK72125CS Cout=1.0uF(MLCC)
Vout:1V/div Vcont:2V/div Time:400usec/div
!TK72185CS Cout=1.0uF(MLCC)
Vout:2V/div Vcont:2V/div Time:200usec/div
!TK72125CS Cout=1.0uF(MLCC)
Vout:1V/div Vcont:2V/div Time:4msec/div
!TK72185CS Cout=1.0uF(MLCC)
Vout:2V/div Vcont:2V/div Time:2msec/div
Vcont Vcont
←0V ←0V
Vout Vout
Vout
Vcont
Vout
Vcont
←0V ←0V
Cn
p
=102
Cn
p
=103
Cn
p
=102
Cn
p
=103
Cn
p
=473
Cn
p
=104
Cn
p
=473 Cn
p
=104
f=1Hz(Cnp Full discharge) f=1Hz(Cnp Full discharge)
f=1Hz(Cnp Full discharge) f=1Hz(Cnp Full discharge)
TK721xxCS
GC3-K020B Page 16
Vin=-VoutTYP-1.5V,Cin=1.0uF(MLCC),Iout=100mA
!TK72125CS
Vout:1V/div Vcont:2V/div Time:400usec/div
!TK72185CS
Vout:2V/div Vcont:2V/div Time:400usec/div
!TK72125CS
Control frequency variable
Vout:1V/div Vcont:2V/div Time:200usec/div
!TK72185CS
Control frequency variable
Vout:2V/div Vcont:2V/div Time:400usec/div
Rise-time of the output voltage. changes by Cout and Cnp.
Moreover, the rise-time changes by the charge situation of Cnp. Standing up from the state that the charge came off
completely slows most.
Vout
Vcont
Vout
Vcont
←0V ←0V
Cout=1uF/10uF/22uF
Cout=1uF/10uF/22uF
Cnp=103
CoutType=MLCC Cnp=103
CoutType=MLCC
Vout ←0V
f=100/50/1Hz
Vcont
Vout
Vcont
←0V
f=100/50/1Hz
Cnp=103
Cout=1.0uF(MLCC)
Cnp=103
Cout=1.0uF(MLCC)
f=1Hz(Cnp Full discharge) f=1Hz(Cnp Full discharge)
Vout ON
Vout OFF
Vout ON
Vout OFF
TK721xxCS
GC3-K020B Page 17
Vin=-VoutTYP-1.5V,Cin=1.0uF(MLCC),Cout=1.0uF(MLCC),Cnp=0.01uF,Iout=100mA
!TK72125CS
Vout:2V/div Vcont:1V/div Time:100usec/div
!TK72185CS
Vout:2V/div Vcont:1 V/div Time:400usec/div
!TK72125CS
Vout:2V/div Vcont:1V/div Time:100usec/div
!TK72185CS
Vout:2V/div Vcont:1V/div Time:1msec/div
The turn on time will be largely affected by Iout and Cout,but not by Cnp.
Vout
Vcont
Vout
Vcont
0V→
Iout=10/50/100mA
Vout
Vcont
Vout
Vcont
Cout=1.0/4.7/10uF
OFF
ON
Iout=10/50/100mA
0V→
OFF
ON
0V→
ON
OFF
Cout=1.0/4.7/10uF
0V→
ON
OFF
TK721xxCS
GC3-K020B Page 18
10-5 Line Transient
Vin=-VoutTYP-1.5→-VoutTYP-2.5V,Cin=1.0uF(MLCC),Cnp=0.01uF,Iout=100mA
Cin
Vout Cout
Cnp
1
3
2
5
4
VEE
Vout
Np GND
Cont
Iout
V
↑
Vin=Vouttyp-2.5V
Vin=Vouttyp-1.5V
↓
Vin
!TK72125CS
Vout:100mV/div Vin:1V/div Time:100usec/div
!TK72185CS
Vout:100mV/div Vin:1V/div Time:100usec/div
!TK72125CS
Vout:100mV/div Vin:1V/div Time:100usec/div
!TK72185CS
Vout:100mV/div Vin:1V/div Time:100usec/div
Vout
Vin=VoutTYP-2.5V
VoutTYP-1.5V
Vin
Cout=1.0uF
(
MLCC
)
Cout=2.2uF
(
MLCC
)
Vout
Vin=VoutTYP-2.5V
VoutTYP-1.5V
Vin
Cout=1.0uF
(
MLCC
)
Cout=2.2uF
(
MLCC
)
Vout
Vin
Cout=1.0uF
(
Tantalum
)
Cout=2.2uF
(
Tantalum
)
Vout
Vin
Cout=1.0uF
(
Tantalum
)
Cout=2.2uF
(
Tantalum
)
Vin=VoutTYP-2.5V
VoutTYP-1.5V
Vin=VoutTYP-2.5V
VoutTYP-1.5V
TK721xxCS
GC3-K020B Page 19
10-6 Noise
Vin= VoutTYP-1.5(V) Vcont=0V Cin=1.0uF(MLCC) BPF400 ~ 80kHz Iout=100mA
! Cout=1.0uF(MLCC) ! Cout=1.0uF(Tantalum)
0
50
100
150
200
250
300
350
400
450
500
1000 10000 100000
Cnp (pF)
Noise (uVrms
)
0
50
100
150
200
250
300
350
400
450
500
1000 10000 100000
Cnp (pF)
Noise (uVrms
)
! Cout=1.0uF(MLCC) Cnp=103 ! Cout=1.0uF(MLCC) Cnp=103 Iout=100mA
0
20
40
60
80
100
120
140
160
180
200
050100150
Iout (mA)
Noise (uVrms)
0
20
40
60
80
100
120
140
160
180
200
246810
Vout (-V)
Noise (uVrms)
TK72185CS TK72185CS
TK72125CS TK72125CS
TK72185CS
TK72125CS
TK721xxCS
GC3-K020B Page 20
10-7 Ripple Rejection
Vin=VoutTYP-2.0(V) Vripple=500mVp-p,Cnp=0.01uF,Iout=10mA
View point
Cout
Cnp
1
3
2
5
4
VEE
Vout
Np GND
Cont
Iout
Vripple=500mVp-p
Vin=Vouttyp-2.0V
!TK72125C S Cout=1.0u F(M LC C) !TK72185C S Cout=1.0u F(M LC C)
!TK72125C S Cout=2.2u F(M LC C) !TK72185C S Cout=2.2u F(M LC C)
10dB/div
0dB→
10dB/div
0dB→
10dB/div
0dB→
10dB/div
0dB→
TK721xxCS
GC3-K020B Page 21
Vin=VoutTYP-2.0(V) Vripple=500mVp-p,Cnp=0.01uF,Iout=10mA
!TK72125C S Cout=1.0u F(Ta ntal um ) !TK72185CS Cout= 1.0u F(Ta ntalum)
!
!!
!TK721xx CS f=1kHz,Vripple=100mV p-p
-60
-50
-40
-30
-20
-10
0
0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6
Vout-Vin (V)
R.R (dB)
Io=10mA
Io=100mA
10dB/div
0dB→
10dB/div
0dB→
TK721xxCS
GC3-K020B Page 22
11. PIN DESCRIPTION
Pin No Pin
Description Internal Equivalent Circuit Description
1 Cont
1
GND
GNDGND
GND
Cont
ContCont
Cont
52k
52k52k
52k
38k
38k38k
38k
ON/OFF control terminal
Please do not apply -0.4V or less to this pin.
The current might flow from GND.
2 VEE - Input terminal
3Np
GND
GNDGND
GND
Vref
VrefVref
Vref
3
Np
NpNp
Np
10k
10k10k
10k
500k
500k500k
500k
27k
27k27k
27k
Noise pass terminal
4 GND - GND terminal
5 Vout
Vout
VoutVout
Vout
6
VEE
VEEVEE
VEE
GND
GNDGND
GND
R1
R1R1
R1
R2
R2R2
R2
Vref
VrefVref
Vref
Output terminal
1
21
RRR
VrefVout +
×=
TK721xxCS
GC3-K020B Page 23
12. AP PLICATIONS INFORMATION
12-1.Definition of term
Relating Characteristic
note Each characteristics will be measured in a short
period not to be influenced by joint temperature (Tj).
*Output voltage (Vout)
The output voltage is specified with Vin= VoutTYP+1V
and Iout=5mA
*Output current (Iout)
Output current, which can be used continuously (It is
the range where overheating protection of the IC does not
operate.)
*Peak output current (IoutPEAK)
The rated output current is specified under the
condition where the output voltage drops 90% by
increasing the output current, compared to the value
specified at Vin=VoutTYP-1.5V.
*Dropout voltage (Vdrop)
It is an I/O voltage difference when the circuit stops
the stable operation by decreasing the input voltage.
It is measured when the output voltage drops 100mV
from its nominal value by decreasing the input voltage
gradually.
*Line Regulation (LinRe g)
It is the fluctuations of the output voltage value when
the input voltage is changed.
*Load Regulation (LoaReg)
It is the fluctuations of output voltage value when the
input voltage is assumed to be VoutTYP -1.5V, and the
load current is changed.
*Ripple Rejecti on (R.R)
Ripple rejection is the ability of the regulator to
attenuate the ripple content of the input voltage at the
output. It is measured with the condition of
Vin=Vout-2.0V. Ripple rejection is the ratio of the ripple
content between the output vs. input and is expressed in
dB
*Standby current (Istandby)
It is an input current which flows to the control terminal,
when the IC is turned off.
Relating Protection Circuit
*Over Current Protection
It is a function to protect the IC by limiting the output
current when excessive current flows to IC, such as the
output is connected to GND, etc.
*Thermal Protection
It protects the IC not to exceed the permissible power
consumption of the package in case of large power loss
inside the regulator.
The output is turned off when the chip reaches around
150°C, but it turns on again when the temperature of the
chip decreases.
*ESD
It is tested by connecting charged capacitor to GND
pin and Vin pin.
MM 200pF 0Ω 200Vmin
HBM 100pF 1.5kΩ 2000Vmin
TK721xxCS
GC3-K020B Page 24
12-2. ESR Stability
IC does operates with 1.0uF Cout. If it is 1.0uF or larger,
the capacitor of any type can be used in all range without
considering ESR. But due to the parts are uneven, please
enlarge the capacitance as much as possible. With larger
capacity, the output noise decreases more. In addition, the
response to the load change, etc. can be improved. The IC
won’t be damaged by enlarging the capacity.
The input capacitor is necessary in case the battery
voltage drops, the power supply impedance increases, or
the distance to the power supply is far. 1 input capacitor
might be necessary for each 1 IC or for several ICs. It
depends on circuit condition. Please confirm the stability
by each circuit.
Generally, Multi layer ceramic capacitor (MLCC) has the
temperature characteristic and the voltage characteristic.
Please select parts in consideration of the voltage and the
temperature used.
Stability area graph (Vout=-2.0 ~ -9.5V)
Condition:Vin=VoutTYP-1.5V Cin=0.1µF(MLCC)
Cout=1.0uF
0.01
0.1
1
10
100
0 50 100 150
Iout (mA)
ESR (Ω)
*The output can be seen as oscillated when the
overheating protection or the overcurrent protection start
operation, or the input voltage is low. In this case, please
lower the power consumption, decrease the load current
or make the input voltage higher.
Selection of Cout
Generally, a ceramic capacitor has the temperature
characteristic and the voltage characteristic. Please select
parts in consideration of the voltage and the temperature
used. TOKO recommend B characteristic type.
Stable area
Unstable area
TK721xxCS
GC3-K020B Page 25
12-3.
Operating Region and Power Dissipation
The power dissipation of the device is dependent on the
junction temperature. Therefore, the package dissipation
is assumed to be an internal limitation. The package itself
does not have enough heat radiation characteristic due to
the small size. Heat runs away by mounting IC on PCB.
This value changes by the material, copper pattern etc. of
PCB.
The overheating protection operates when there is a lot of
loss inside the regulator (Ambient temperature high, heat
radiation bad, etc.). The output current and the output
voltage will drop when the protection circuit operates.
When joint temperature (Tj) reaches the set temperature,
IC stops the operation. However, operation begins at once
when joint temperature(Tj) decrease.
The thermal resistance when mounted on PCB
The chip joint temperature during operation is shown by
Tj=θja×Pd+Ta. Joint part temperature (Tj) of
TK721xxCS is limited around 150°C with the
overheating protection circuit. Pd is the value when the
overheating protection circuit starts operation.
When you assume the ambient temperature to be 25°C,
150=θja×Pd(W)+25
θja×Pd=125
θja=125/Pd (°C /W)
Example of mounting substrate
PCB Material: Two layer glass epoxy substrate
(x=30mm,y=30mm,t=1.0mm,Copper pattern thickness
35um)
Please do derating with 5.9mW/°C at Pd=736mW and
25°C or higher. Thermal resistance is (θja=170°C /W)
Method of obtaining Pd easily
Connect output terminal to GND(short circuited), and
measure the input current by increasing the input voltage
gradually up to 10V. The input current will reach the
maximum output current, but will decrease soon
according to the chip temperature rising, and will finally
enter the state of thermal equilibrium (natural air cooling)
The input current and the input voltage of this state will
be used to calculate the Pd.
Pd(mW) ≅ Vin (V) × Iin (mA)
When the device is mounted, mostly achieve 600mW or
more.
0 25 50 75 100 150
Pd(mW)
Pd
D Pd
2
3
5
4
Ta (℃)
Procedure (When mounted on PCB).
1.Find Pd (Vin×Iin when the output is short-circuited).
2. Plot Pd against 25°C.
3. Connect Pd to the point corresponding to the 150°C with a
straight line.
4. Pull a vertical line from the maximum operating temperature in
your design (e.g., 75°C).
5. Read the value of Pd against the point at which the vertical line
intersects the derating curve(DPd).
6. DPd ÷ (Vinmax−Vout)=Iout (at 75°C)
The maximum output current at the highest operating
temperature will be Iout ≅
≅≅
≅ DPd ÷
÷÷
÷ (VinMax−
−−
−Vout).
Please use the device at low temperature with better
radiation. The lower temperature provides better quality.
TK721xxCS
GC3-K020B Page 26
The operation area
PCB Material : Two layer glass epoxy substrate
(x=30mm,y=30mm,t=1.0mm,Copper pattern thickness
35um)
Pd when mounted on the substrate mentioned above
(Ta=25°C)
SOT23-5=736mW (derating –5.9mW)
The current which can be used continuously with
Ta=25°C min is calculated by the following.
VoutVin Ta
mAIout −−×−
=)25(9.5736
)( - SOT23-5
*Iout<150mA
The operation area is the part enclosed in the line
including the “0” mentioned in graph1
The overheating sensor may operate, or the output
voltage may drop outside those area.
The heat radiation characteristic changes in various
conditions, so please check under your condition.
graph1
0 25 50 85 125 150
Pd
(mW)
200
400
600
800
1000
Unit-4.0mW
O N P CB - 5 .9 mW
graph2
IoutMAX vs IN-OUT VOLTAGE DIFF
(SOT23-5)
0
20
40
60
80
100
120
140
160
012345678910
IN-OUT VOLTAGE DIFF (V)
Iout MAX (mA)
Ta=+85℃
Ta=+85℃Ta=+85℃
Ta=+85℃
Ta=+70℃
Ta=+70℃Ta=+70℃
Ta=+70℃
Ta=+50℃
Ta=+50℃Ta=+50℃
Ta=+50℃
Ta=+25℃
Ta=+25℃Ta=+25℃
Ta=+25℃
Unit
ON PCB
Ta (°
°°
°C)
TK721xxCS
GC3-K020B Page 27
12-4 Application hint
*When using together with Positive output regulator
Positive REG
TK721xxC
Negative REG
Vout
VoutVout
Vout
Vout
VoutVout
Vout
Load
LoadLoad
Load
When using positive output regulator together with this
device, sometimes the voltage may not be outputted. To
solve this problem, please connect Schottkey diode
between GND and output, or change the timing of On/Off.
*When not using ON/OFF function
Please connect the Cont terminal to GND.
*Notes when evaluating with output terminal is
connected to GND(short-circuit)
The output terminal becomes plus potential by the
resonance of Cout (C element) connected to output and
the short-circuit line (L element). When the output
terminal becomes positive, parasitism Tr is caused inside
the IC. The latch-up phenomenon occurs and in the worst
case, IC may be damaged.(f0=1 / 2π√(L C))
This resonance appears remarkably when using a ceramic
capacitor with small ESR, etc. This can be solved by
connecting 2Ω resistance in series. As a result, the
latch-up phenomenon in IC can be prevented.
Generally, tantalum capacitor has enough ESR value and
the influence of the resonance decreases.
TK721xxCS
GC3-K020B Page 28
13. NOTES
! Please be sure that you carefully discuss your planned
purchase with our office if you intend to use the products in
this application manual under conditions where particularly
extreme standards of reliability are required, or if you intend
to use products for applications other than those listed in this
application manual.
" Power drive products for automobile, ship or aircraft
transport systems; steering and navigation systems,
emergency signal communications systems, and any
system other than those mentioned above which include
electronic sensors, measuring, or display devices, and
which could cause major damage to life, limb or property
if misused or failure to function.
" Medical devices for measuring blood pressure, pulse,
etc., treatment units such as coronary pacemakers and heat
treatment units, and devices such as artificial organs and
artificial limb systems which augment physiological
functions.
" Electrical instruments, equipment or systems used in
disaster or crime prevention.
! Semiconductors, by nature, may fail or malfunction in
spite of our devotion to improve product quality and
reliability. We urge you to take every possible precaution
against physical injuries, fire or other damages which may
cause failure of our semiconductor products by taking
appropriate measures, including a reasonable safety margin,
malfunction preventive practices and fire-proofing when
designing your products.
! This application manual is effective from Dec. 2004 .
Note that the contents are subject to change or
discontinuation without notice. When placing orders, please
confirm specifications and delivery condition in writing.
! TOKO is not responsible for any problems nor for any
infringement of third party patents or any other intellectual
property rights that may arise from the use or method of use
of the products listed in this application manual. Moreover,
this application manual does not signify that TOKO agrees
implicitly or explicitly to license any patent rights or other
intellectual property rights which it holds.
! None of the ozone depleting substances(ODS) under the
Montreal Protocol are used in our manufacturing process.
14. OFFICES
If you need more information on this product and other
TOKO products, please contact us.
! TOKO Inc. Headquarters
1-17, Higashi-yukigaya 2-chome, Ohta-ku, Tokyo,
145-8585, Japan
TEL: +81.3.3727.1161
FAX: +81.3.3727.1176 or +81.3.3727.1169
Web site: http://www.toko.co.jp/
! TOKO America
Web site: http://www.toko.com/
! TOKO Europe
Web site: http://www.tokoeurope.com/
! TOKO Hong Kong
Web site: http://www.toko.com.hk/
! TOKO Taiwan
Web site: http://www.tokohc.com.tw/
! TOKO Singapore
Web site: http://www.toko.com.sg/
! TOKO Seoul
Web site: http://www.toko.co.kr/
! TOKO Manila
Web site: http://www.toko.com.ph/
! TOKO Brazil
Web site: http://www.toko.com.br/
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