TOSHIBA TCV7108FN

TCV7108FN
TOSHIBA CMOS Integrated Circuit
Silicon Monolithic
TCV7108FN
Buck DC-DC Converter IC
The TCV7108FN is a single-chip buck DC-DC converter IC.
The TCV7108FN contains high-speed and low-on-resistance power
MOSFETs for the main switch and synchronous rectifier to achieve
high efficiency.
The TCV7108FN is a product that improves the load response
characteristic of TCV7104FN.
Features

Enables up to 2.5A (@ VIN  5V) ／2 A (@ VIN  3.3V) of load
current (IOUT) with a minimum of external components.

High efficiency:   95% (typ.)
(@VIN  5 V, VOUT  3.3 V, IOUT  0.7 A)

Operating voltage range: VIN = 2.7 to 5.6 V

Low ON-resistance: RDS (ON)  0.18  (high-side)  0.12  (low-side) typical (@VIN  5 V, Tj  25°C)

High oscillation frequency: fOSC  1500 kHz (typ.)
Weight: 0.017 g (typ.)

Feedback voltage: VFB = 0.8 V  1% (@Tj  0 to 85°C)

Uses internal phase compensation to achieve high efficiency and high load response characteristic with a
minimum of external components.

Allows the use of a small surface-mount ceramic capacitor as an output filter capacitor and the high load
response characteristic is obtained by the capacity value of 40μF.

Housed in a small surface-mount package (PS-8) with a low thermal resistance.

Soft-start time adjustable by an external capacitor
Part Marking
Pin Assignment
Part Number (or abbreviation code)
LX
8
EN
SS
7
6
VFB
5
Lot No.
V108
The dot () on the top surface indicates pin 1.
*:
1
2
3
4
PGND
VIN1
VIN2
SGND
The lot number consists of three digits. The first digit represents the last digit of the year of manufacture, and the
following two digits indicates the week of manufacture between 01 and either 52 or 53.
Manufacturing week code
(The first week of the year is 01; the last week is 52 or 53.)
Manufacturing year code (last digit of the year of manufacture)
This product has a MOS structure and is sensitive to electrostatic discharge. Handle with care.
The product(s) in this document (“Product”) contain functions intended to protect the Product from temporary
small overloads such as minor short-term overcurrent, or overheating. The protective functions do not necessarily
protect Product under all circumstances. When incorporating Product into your system, please design the system (1)
to avoid such overloads upon the Product, and (2) to shut down or otherwise relieve the Product of such overload
conditions immediately upon occurrence. For details, please refer to the notes appearing below in this document and
other documents referenced in this document.
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TCV7108FN
Ordering Information
Part Number
Shipping
TCV7108FN (TE85L, F)
Embossed tape (3000 units per reel)
Block Diagram
VIN2
VIN1
Current detection
Oscillator
Slope
Compensation
Under
voltage
lockout
Control logic
-
Driver
Constant-current
source (8 A)
VFB
LX
Error amplifier
Phase compensation
-
SS
EN
+
Short-Circuit
Protection
+
Soft Start
Ref. Voltage (0.8V)
PGND
SGND
Pin Description
Pin No.
Symbol
1
PGND
2
VIN1
3
VIN2
4
SGND
5
VFB
Description
Ground pin for the output section
Input pin for the output section
This pin is placed in the standby state if VEN=”L”. Standby current is 10 A or less.
Input pin for the control section
This pin is placed in the standby state if VEN=”L”. Standby current is 10 A or less.
Ground pin for the control section
Feedback pin
This input is fed into an internal error amplifier with a reference voltage of 0.8 V (typ.).
Soft-start pin
6
SS
When the SS input is left open, the soft-start time is 1 ms (typ.). The soft-start time can be adjusted
with an external capacitor. The external capacitor is charged from a 8A (typ.) constant-current
source, and the reference voltage of the error amplifier is regulated between 0 V and 0.8 V. The
external capacitor is discharged when VEN=”L” and in case of undervoltage lockout or thermal
shutdown.
Enable pin
7
EN
When EN  1.5 V (@ VIN  5 V), the internal circuitry is allowed to operate and thus enable the
switching operation of the output section. When EN  0.5 V (@ VIN  5 V), the internal circuitry is
disabled, putting the TCV7108FN in Standby mode.
This pin has an internal pull-down resistor of approx. 500 k.
8
LX
Switch pin
This pin is connected to high-side P-channel MOSFET and low-side N-channel MOSFET.
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2011-10-03
TCV7108FN
Absolute Maximum Ratings (Ta  25°C)
Characteristics
Symbol
Rating
Unit
Input pin voltage for the output section
(Note 1)
VIN1
0.3 to 7
V
Input pin voltage for the control section
(Note 1)
VIN2
0.3 to 7
V
Feedback pin voltage
(Note 1)
VFB
0.3 to 7
V
Soft-start pin voltage
(Note 1)
VSS
0.3 to 7
V
Enable pin voltage
(Note 1)
VEN
0.3 to 7
V
VEN-VIN2
VEN – VIN2  0.3
V
VLX
0.3 to 7
V
ILX
2.9
A
PD
0.9
W
Tjopr
40 to125
°C
Tj
150
°C
Tstg
55 to150
°C
VEN – VIN2 voltage difference
Switch pin voltage
(Note 2)
Switch pin current
Power dissipation
(Note 3)
Operating junction temperature
Junction temperature
(Note 4)
Storage temperature
Note: Using continuously under heavy loads (e.g. the application of high temperature/current/voltage and the
significant change in temperature, etc.) may cause this product to decrease in the reliability significantly even if
the operating conditions (i.e. operating temperature/current/voltage, etc.) are within the absolute maximum
ratings and the operating ranges.
Please design the appropriate reliability upon reviewing the Toshiba Semiconductor Reliability Handbook
(“Handling Precautions”/“Derating Concept and Methods”) and individual reliability data (i.e. reliability test
report and estimated failure rate, etc)
Note 1: Using this product continuously may cause a decrease in the reliability significantly even if the operating
conditions are within the absolute maximum ratings. Set each pin voltage less than 5.6V taking into
consideration the derating.
Note 2: The switch pin voltage (VLX) doesn’t include the peak voltage generated by TCV7108FN’s switching.
A negative voltage generated in dead time is permitted among the switch pin current (ILX).
Thermal Resistance Characteristics
Characteristics
Symbol
Max
Unit
Thermal resistance, junction to ambient
Rth (j-a)
110.2 (Note 3)
°C/W
Note3:
Single-sided glass epoxy board
FR-4
25.4  25.4  0.8
(Unit: mm)
Note 4: The TCV7108FN may into thermal shutdown at the rated maximum junction temperature. Thermal design is
required to ensure that the rated maximum operating junction temperature, Tjopr, will not be exceeded.
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2011-10-03
TCV7108FN
Electrical Characteristics (Tj  25°C, VIN1  VIN2  2.7 to 5.6 V, unless otherwise specified)
Characteristics
Operating input voltage
Operating current
Symbol
Test Condition
Min
Typ.
Max
Unit
VIN (OPR)

2.7

5.6
V
VIN1  VIN2  VEN  VFB  5 V

450
680
A
VOUT (OPR)
VEN  VIN1  VIN2
0.8


V
IIN (STBY) 1
VIN1  VIN2  5 V, VEN  0 V
VFB  0.8 V


10
IIN (STBY) 2
VIN1  VIN2  3.3 V, VEN  0 V
VFB  0.8 V


10
ILEAK (H)
VIN1  VIN2  5 V, VEN  0 V
VFB  0.8 V, VLX  0 V


10
VIH (EN) 1
VIN1  VIN2  5 V
1.5


VIH (EN) 2
VIN1  VIN2  3.3 V
1.5


VIL (EN) 1
VIN1  VIN2  5 V


0.5
VIL (EN) 2
VIN1  VIN2  3.3 V


0.5
IIH (EN) 1
VIN1  VIN2  5 V, VEN  5 V
6

13
IIH (EN) 2
VIN1  VIN2  3.3 V, VEN  3.3 V
4

9
IIN
Output voltage range
Standby current
High-side switch leakage current
EN threshold voltage
EN input current
VFB input voltage
VFB input current
A
A
V
A
VFB1
VIN  5 V, VEN  5 V, Tj = 0 to 85℃
0.792
0.8
0.808
VFB2
VIN  3.3 V, VEN  3.3 V, Tj = 0 to 85℃
0.792
0.8
0.808
VIN1  VIN2  2.7 to 5.6 V
VFB  VIN2
1

1
RDS(ON)(H)1
VIN1 = VIN2 = 5V , VEN = 5 V
ILX = - 1A

0.18

RDS(ON)(H)2
VIN1 = VIN2 = 3.3 V , VEN = 3.3V
ILX = - 1 A

0.21

RDS(ON)(H)3
VIN1 = VIN2 = 5 V , VEN = 5V
ILX = - 0.1 A , Tj=-40 to 85℃


0.25
RDS(ON)(H)4
VIN1 = VIN2 = 3.3 V , VEN = 3.3V
ILX = - 0.1 A , Tj=-40 to 85℃


0.3
RDS (ON) (L) 1
VIN1  VIN2  5 V, VEN  5 V
ILX  1 A

0.12

RDS (ON) (L) 2
VIN1  VIN2  3.3 V, VEN  3.3 V
ILX  1 A

0.14

RDS (ON) (L) 3
VIN1 = VIN2 = 5 V , VEN = 5V
ILX = 0.1 A , Tj=-40 to 85℃


0.18
RDS (ON) (L) 4
VIN1 = VIN2 = 3.3 V , VEN = 3.3V
ILX = 0.1 A , Tj=-40 to 85℃


0.2
VIN1  VIN2  VEN  5 V
1200
1500
1800
kHz
0.25
0.45
0.65
ms
IFB
High-side switch on-state resistance
Low-side switch on-state resistance
V
A


Oscillation frequency
fOSC
Internal soft-start time
tSS
VIN1  VIN2  5 V, IOUT  0 A, Measured
between 0% and 90% points at VOUT.
External soft-start charge current
ISS
VIN1  VIN2  5 V, VEN  5 V
5
8
13
A
VIN1  VIN2  2.7 to 5.6 V


100
%
TSD
VIN1  VIN2  5 V

150

Hysteresis
TSD
VIN1  VIN2  5 V

15

Detection voltage
VUV
VEN  VIN1  VIN2
2.3
2.45
2.6
Recovery voltage
VUVR
VEN  VIN1  VIN2
2.4
2.55
2.7
Hysteresis
VUV
VEN  VIN1  VIN2

0.1

ILIM1
VIN1 = VIN2 = 4.3 V, VOUT = 2 V
2.7
3.3

ILIM2
VIN1 = VIN2 = 3.3 V, VOUT = 2 V
2.3
2.9

High-side switch duty cycle
Thermal
shutdown (TSD)
Undervoltage
lockout (UVLO)
LX current limit
Detection
temperature
Dmax
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2011-10-03
°C
V
A
TCV7108FN
Note on Electrical Characteristics
The test condition Tj  25°C means a state where any drifts in electrical characteristics incurred by an increase in
the chip’s junction temperature can be ignored during pulse testing.
Application Circuit Example
Figure 1 shows a typical application circuit using a low-ESR electrolytic or ceramic capacitor for COUT.
VIN
VIN1
VIN2
EN
EN
CIN
CC
LX
L
TCV7108FN
VOUT
RFB1
VFB
SS
COUT
CSS
SGND
PGND
RFB2
GND
GND
Figure 1 TCV7108FN Application Circuit Example
Component values (reference value@ VIN  5 V, VOUT  3.3 V, Ta  25°C)
CIN: Input filter capacitor  10 F
(ceramic capacitor: GRM21BB30J106K manufactured by Murata Manufacturing Co., Ltd,
C2012X5R1C106M manufactured by TDK-EPC Corporation.)
COUT: Output filter capacitor  22 F ×2
(ceramic capacitor: GRM21BB30J226M manufactured by Murata Manufacturing Co., Ltd,
C2012X5R0J226M manufactured by TDK-EPC Corporation.)
RFB1: Output voltage setting resistor  7.5 k
RFB2: Output voltage setting resistor  2.4 k
L: Inductor = 1.5 H
(LTF5022T-1R5N3R6-LC or SLF6045T-1R5N4R0-3PF manufactured by TDK-EPC Corporation)
CSS is a capacitor for adjusting the soft-start time.
CC is a decoupling capacitor of Input pin for the control section.
(Connect it when the circuit operation is unstable due to the board layout or a feature of the CIN.)
Examples of Component Values (For Reference Only)
Output Voltage Setting
VOUT
Inductance
L
Input Capacitance
CIN
Output Capacitance
COUT
Feedback Resistor
RFB1
Feedback Resistor
RFB2
1.2 V
1.5 H
10 F
22 F×3
7.5 k
15 k
1.51 V
1.5 H
10 F
22 F×2
16 k
18 k
1.8 V
1.5 H
10 F
22 F×2
15 k
12 k
2.5 V
1.5 H
10 F
22 F×2
5.1 k
2.4 k
3.3 V
1.5 H
10 F
22 F×2
7.5 k
2.4 k
Component values need to be adjusted, depending on the TCV7108FN’s I/O conditions and the board layout.
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2011-10-03
TCV7108FN
Application Notes
Inductor Selection
The inductance required for inductor L can be calculated as follows:
VIN: Input voltage (V)
VIN  VOUT VOUT
VOUT: Output voltage (V)
············· (1)
L

fOSC  IL
VIN
fOSC: Oscillation frequency  1500 kHz (typ.)
IL: Inductor ripple current (A)
*: Generally, IL should be set to approximately 25% of the maximum output current. Since the maximum
output current of the TCV7108FN is 2.5 A, IL should be 0.6 A or so. The inductor should have a current
rating greater than the peak output current of 2.8 A. If the inductor current rating is exceeded, the inductor
becomes saturated, leading to an unstable DC-DC converter operation.
L

VIN  VOUT VOUT

fOSC  IL
VIN
5 V  3.3 V
3.3 V

1500kHz  0.6A 5 V
IL
When VIN  5 V and VOUT  3.3 V, the required inductance can be calculated as follows. Be sure to select an
appropriate inductor, taking the input voltage range into account.
IL
0
T
 1.25H
V
TON  Τ  OUT
VIN
1
fOSC
Figure 2 Inductor Current Waveform
Setting the Output Voltage
A resistive voltage divider is connected as shown in Figure 3 to set the output voltage; it is given by Equation 2
based on the reference voltage of the error amplifier (0.8 V typ.), which is connected to the Feedback pin, VFB.
RFB1 should be up to 30 k or so, because an extremely large-value RFB1 incurs a delay due to parasitic
capacitance at the VFB pin. It is recommended that resistors with a precision of 1% or higher be used for RFB1
and RFB2.
LX
VFB
VOUT
RFB2 RFB1
VOUT


R
 VFB   1  FB1 
R FB2 

 R 
 0.8 V  1  FB1  ········ (2)
 R FB2 
Figure 3 Output Voltage Setting Resistors
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TCV7108FN
Output Filter Capacitor Selection
Use a low-ESR electrolytic or ceramic capacitor as the output filter capacitor. Since a capacitor is generally
sensitive to temperature, choose one with excellent temperature characteristics. When the output voltage
exceeds 1.2 V, the capacitance should be 40 F or greater for applications. Meanwhile 60 F or greater
capacitance is desirable when the output voltage is less than 1.2 V. The capacitance should be set to an optimal
value that meets the system’s ripple voltage requirement and transient load response characteristics. The phase
margin tends to decrease as the output voltage is getting low. Enlarge a capacitance for output flatness when
phase margin is insufficient, or the transient load response characteristics cannot be satisfied. Since the ceramic
capacitor has a very low ESR value, it helps reduce the output ripple voltage; however, because the ceramic
capacitor provides less phase margin, it should be thoroughly evaluated.
Soft-Start Feature
The TCV7108FN has a soft-start feature.
If the SS pin is left open, the soft-start time, tSS, for VOUT defaults to 0.45 ms (typ.) internally.
The soft-start time can be extended by adding an external capacitor (CSS) between the SS and SGND pins. The
soft-start time can be calculated as follows:
t SS2  0.1  C SS ···························· (3)
tSS2: Soft-start time (in seconds) when an external capacitor is
connected between SS and SGND.
CSS: Capacitor value (F)
The soft-start feature is activated when the TCV7108FN exits the undervoltage lockout (UVLO) state after
power-up and when the voltage at the EN pin has changed from logic low to logic high.
Overcurrent Protection（OCP）
The TCV7108FN has maximum current limiting. The TCV7108FN limits the ON time of high side switching
transistor and decreases output voltage when the peak value of the Lx terminal current exceeds switching
terminal peak current limitation ILIM1=3.3A(typ.)@ VIN = 4.3V / ILIM2=2.9A(typ.)@ VIN = 3.3V. When VIN≧4.3V,
The TCV7108FN can operate at IOUT = 2.5A(max). Meanwhile, use it at IOUT = 2A(max) when VIN＜4.3V.
Undervoltage Lockout (UVLO)
The TCV7108FN has undervoltage lockout (UVLO) protection circuitry. The TCV7108FN does not provide
output voltage (VOUT) until the input voltage (VIN2) has reached VUVR (2.55 V typ.). UVLO has hysteresis of 0.1
V (typ.). After the switch turns on, if VIN2 drops below VUV (2.45 V typ.), UVLO shuts off the switch at VOUT.
Undervoltage lockout
recovery voltage VUVR
VIN2
Undervoltage lockout
detection voltage VUV
Hysteresis: VUV
GND
Switching operation starts
VOUT
GND
Switching operation
stops
Soft start
Figure 4 Undervoltage Lockout Operation
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2011-10-03
TCV7108FN
Thermal Shutdown (TSD)
The TCV7108FN provides thermal shutdown. When the junction temperature continues to rise and reaches
TSD (150°C typ.), the TCV7108FN goes into thermal shutdown and shuts off the power supply. TSD has a
hysteresis of about 15°C (typ.). The device is enabled again when the junction temperature has dropped by
approximately 15°C from the TSD trip point. The device resumes the power supply when the soft-start circuit is
activated upon recovery from TSD state.
Thermal shutdown is intended to protect the device against abnormal system conditions. It should be ensured
that the TSD circuit will not be activated during normal operation of the system.
TSD detection
temperature: TSD
Recovery from TSD
Hysteresis: TSD
Tj
0
Switching operation starts
VOUT
GND
Switching operation stops
Soft start
Figure 5 Thermal Shutdown Operation
Usage Precautions

The input voltage, output voltage, output current and temperature conditions should be considered when
selecting capacitors, inductors and resistors. These components should be evaluated on an actual system
prototype for best selection.

Parts of this product in the surrounding are examples of the representative, and the supply might become
impossible. Please confirm latest information when using it.

External components such as capacitors, inductors and resistors should be placed as close to the TCV7108FN as
possible.

The TCV7108FN has an ESD diode between the EN and VIN2 pins. The voltage between these pins should
satisfy VEN  VIN2  0.3 V.

CIN should be connected as close to the PGND and VIN1 pins as possible. Operation might become unstable due
to board layout. In that case, add a decoupling capacitor (CC) of 0.1 F to 1 F between the SGND and VIN2 pins.

The minimum programmable output voltage is 0.8 V (typ.). If the difference between the input and output
voltages is small, the output voltage might not be regulated accurately and fluctuate significantly.

When TCV7108FN is in operation, a negative voltage is generated since regeneration current flows through the
switch pin (LX). Even if the current flows through the low side parasitic diode during the dead time of switching
transistor, operation is undisturbed so an external flywheel diode is unnecessary. If there is the possibility of an
external negative voltage generation, add a diode for protection.

SGND pin is connected with the back of IC chip and serves as the heat radiation pin. Secure the area of a GND
pattern as large as possible for greater of heat radiation.

The overcurrent protection circuits in the Product are designed to temporarily protect Product from minor
overcurrent of brief duration. When the overcurrent protective function in the Product activates, immediately
cease application of overcurrent to Product. Improper usage of Product, such as application of current to Product
exceeding the absolute maximum ratings, could cause the overcurrent protection circuit not to operate properly
and/or damage Product permanently even before the protection circuit starts to operate.

The thermal shutdown circuits in the Product are designed to temporarily protect Product from minor
overheating of brief duration. When the overheating protective function in the Product activates, immediately
correct the overheating situation. Improper usage of Product, such as the application of heat to Product
exceeding the absolute maximum ratings, could cause the overheating protection circuit not to operate properly
and/or damage Product permanently even before the protection circuit starts to operate.
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2011-10-03
TCV7108FN
Typical Performance Characteristics
IIN – Tj
IIN – VIN
600
(A)
400
IIN
400
Operating current
(A)
500
Operating current
500
IIN
600
300
200
100
VEN  VFB  VIN
Tj  25°C
0
0
1
2
3
Input voltage
4
VIN
5
300
200
100
VEN VIN  5 V
VFB  VIN
0
6
-50
(V)
-25
25
50
75
Junction temperature
IIN – Tj
100
Tj
125
(°C)
VIH(EN), VIL(EN) – Tj
2
600
400
EN threshold voltage
VIH(EN), VIL(EN) (V)
(A)
IIN
VIN  5 V
500
Operating current
0
300
200
100
VEN VIN  3.3 V
VFB VIN
-25
0
25
50
Junction temperature
75
100
Tj
(°C)
VIH(EN)
1
VIL(EN)
0.5
0
0
-50
1.5
-50
125
-25
0
25
Junction temperature
VIH(EN), VIL(EN) – Tj
75
50
Tj
100
125
(°C)
IIH(EN) – VEN
2
20
VIN  5.6 V
VIN  3.3 V
Tj  25°C
1.5
EN input current
IIH(EN) (A)
EN threshold voltage
VIH(EN), VIL(EN) (V)
16
VIH(EN)
1
VIL(EN)
0.5
12
8
4
0
0
-50
-25
0
25
50
Junction temperature
75
Tj
100
125
0
(°C)
1
2
3
EN input voltage
9
4
VEN
5
6
(V)
2011-10-03
TCV7108FN
IIH(EN) – Tj
VUV, VUVR – Tj
14
2.6
Under voltage lockout
voltageVUV,VUVR (V)
VIN  5 V
VEN  5 V
EN input current
IIH(EN) (A)
12
10
8
Recovery voltage VUVR
2.5
Detection voltage VUV
2.4
VEN  VIN
6
2.3
-50
-25
0
25
50
Junction temperature
75
100
Tj
(°C)
125
-50
-25
0
100
Tj
125
(°C)
VFB – VIN
VFB (V)
(V)
VEN  VIN
VOUT  1.2 V
Tj  25°C
VFB input voltage
VOUT
Output voltage
75
0.84
1.5
1
0.5
0
VEN  VIN
VOUT  1.2 V
Tj  25°C
0.82
0.8
0.78
0.76
2.2
2.3
2.4
Input voltage
2.5
2.6
VIN
2.7
2
(V)
3
4
Input voltage
5
VIN
6
(V)
VOUT – VIN
VFB – Tj
0.82
30
(mV)
VIN  5 V
VOUT  1.2 V
VEN  VIN
VOUT  1.2 V , IOUT = 0 mA
L 1.5 H , COUT  22 F ×3
Ta  25°C
20
VOUT
0.81
10
0
0.8
Output voltage
VFB (V)
50
Junction temperature
VOUT – VIN
2
VFB input voltage
25
0.79
0.78
-10
-20
-30
-50
-25
0
25
50
Junction temperature
75
Tj
100
2
125
3
4
Input voltage
(°C)
10
5
VIN
6
(V)
2011-10-03
TCV7108FN
fOSC – Tj
fOSC – VIN
1800
1800
(kHz)
fOSC
1600
Oscillation frequency
1600
Oscillation frequency
(kHz)
VIN  5 V
1700
fOSC
Tj  25°C
1700
1500
1400
1300
1200
1500
1400
1300
1200
2
3
4
Input voltage
5
VIN
-50
6
(V)
-25
0
50
Junction temperature
ISS – VIN
75
Tj
100
125
(°C)
ISS – Tj
0
0
Tj  25°C
VIN  5 V
-2
External soft-start charge current
ISS (A)
External soft-start charge current
ISS (A)
25
-4
-6
-8
-10
-12
-14
-2
-4
-6
-8
-10
-12
-14
2
3
4
Input voltage
5
VIN
-50
6
(V)
-25
0
25
50
Junction temperature
75
Tj
100
125
(°C)
ISS – Tj
External soft-start charge current
ISS (A)
0
VIN 3.3 V
-2
-4
-6
-8
-10
-12
-14
-50
-25
0
25
50
Junction temperature
75
100
Tj
(°C)
125
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TCV7108FN
VOUT – IOUT
10
5
Output voltage
0
(mV)
VIN  5 V , VOUT  3.3 V
L  1.5 H , COUT 22 F×2
Ta  25°C
VOUT
(mV)
VOUT
10
Output voltage
20
-10
-20
-30
0.5
1
1.5
Output current
2
IOUT
-10
0.5
(A)
1
2.5
(A)
 – IOUT
VIN 3.3V , VOUT 1.2 V
L  1.5 H , COUT 22F×3
Ta  25°C
(%)
90
Efficiency
0
-5
80
70
60
VIN  5 V , VOUT  3.3V
L  1.5 H , COUT 22 F×2
Ta  25°C
-10
50
0.5
0
1
Output current
1.5
IOUT
0
2
0.5
1
1.5
Output current
(A)
IOUT
2
2.5
(A)
 – IOUT
 – IOUT
90
90
(%)
100
100
80

70
Efficiency
(%)

IOUT
2
100
-15
Efficiency
1.5
Output current

(mV)
VOUT
-5
0
VOUT – IOUT
Output voltage
0
2.5
15
5
VIN  5 V , VOUT  1.2 V
L  1.5H , COUT 22 F×3
Ta  25°C
-15
0
10
VOUT – IOUT
15
30
80
70
60
60
VIN  5 V , VOUT  1.2V
L  1.5 H , COUT  22 F×3
Ta  25°C
50
0
0.5
1
Output current
1.5
IOUT
2
VIN 3.3 V , VOUT  1.2V
L  1.5H , COUT 22 F×3
Ta  25°C
50
0
2.5
0.5
1
Output current
(A)
12
1.5
IOUT
2
(A)
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TCV7108FN
Overcurrent Protection
Overcurrent Protection
4
2
(V)
(V)
Output voltage
VOUT
VOUT
3
Output voltage
VIN  5V , VOUT  1.2V
L  1.5H , COUT  22 F×3
Ta  25°C
2
1
VIN  5V , VOUT  3.3V
L  1.5H , COUT  22 F×2
Ta  25°C
2
3
Output current
1
0.5
0
0
1
1.5
IOUT
1
4
(A)
2
3
Output current
4
IOUT
(A)
Overcurrent Protection
2
Output voltage
VOUT
(V)
VIN  3.3V , VOUT  1.2 V
L  1.5H , COUT  22 F×3
Ta  25°C
1.5
1
0.5
0
1
2
3
Output current
IOUT
4
(A)
Startup Characteristics
(Internal Soft-Start Time)
VIN  5 V
VOUT  3.3 V
Ta  25°C
L  1.5H
COUT  22 F×2
Startup Characteristics
(CSS  0.1 F)
VIN  5 V
VOUT  3.3 V
Ta  25°C
L  1.5 H
COUT  22 F×2
Output voltage: VOUT (1V/div)
Output voltage: VOUT (1V/div)
EN voltage: VEN:LH
EN voltage: VEN:LH
100 s/div
2 ms/div
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TCV7108FN
Load Response Characteristics
Load Response Characteristics
VIN 5 V , VOUT  3.3 V , Ta  25°C
L  1.5 H , COUT  22 F×2
VIN 5 V , VOUT  1.2 V , Ta  25°C
L  1.5 H , COUT  22 F×3
Output voltage: VOUT (200 mV/div)
Output voltage: VOUT (100 mV/div)
Output current: IOUT :
(10mA2A10mA)
Output current: IOUT :
(10mA2A10mA)
100 s/div
100 s/div
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2011-10-03
TCV7108FN
Package Dimensions
Weight: 0.017 g (typ.)
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TCV7108FN
RESTRICTIONS ON PRODUCT USE
 Toshiba Corporation, and its subsidiaries and affiliates (collectively “TOSHIBA”), reserve the right to make changes to the information
in this document, and related hardware, software and systems (collectively “Product”) without notice.
 This document and any information herein may not be reproduced without prior written permission from TOSHIBA. Even with
TOSHIBA’s written permission, reproduction is permissible only if reproduction is without alteration/omission.
 Though TOSHIBA works continually to improve Product’s quality and reliability, Product can malfunction or fail. Customers are
responsible for complying with safety standards and for providing adequate designs and safeguards for their hardware, software and
systems which minimize risk and avoid situations in which a malfunction or failure of Product could cause loss of human life, bodily
injury or damage to property, including data loss or corruption. Before customers use the Product, create designs including the Product,
or incorporate the Product into their own applications, customers must also refer to and comply with (a) the latest versions of all
relevant TOSHIBA information, including without limitation, this document, the specifications, the data sheets and application notes for
Product and the precautions and conditions set forth in the “TOSHIBA Semiconductor Reliability Handbook” and (b) the instructions for
the application with which the Product will be used with or for. Customers are solely responsible for all aspects of their own product
design or applications, including but not limited to (a) determining the appropriateness of the use of this Product in such design or
applications; (b) evaluating and determining the applicability of any information contained in this document, or in charts, diagrams,
programs, algorithms, sample application circuits, or any other referenced documents; and (c) validating all operating parameters for
such designs and applications. TOSHIBA ASSUMES NO LIABILITY FOR CUSTOMERS’ PRODUCT DESIGN OR APPLICATIONS.
 Product is intended for use in general electronics applications (e.g., computers, personal equipment, office equipment, measuring
equipment, industrial robots and home electronics appliances) or for specific applications as expressly stated in this document.
Product is neither intended nor warranted for use in equipment or systems that require extraordinarily high levels of quality and/or
reliability and/or a malfunction or failure of which may cause loss of human life, bodily injury, serious property damage or serious public
impact (“Unintended Use”). Unintended Use includes, without limitation, equipment used in nuclear facilities, equipment used in the
aerospace industry, medical equipment, equipment used for automobiles, trains, ships and other transportation, traffic signaling
equipment, equipment used to control combustions or explosions, safety devices, elevators and escalators, devices related to electric
power, and equipment used in finance-related fields. Do not use Product for Unintended Use unless specifically permitted in this
document.
 Do not disassemble, analyze, reverse-engineer, alter, modify, translate or copy Product, whether in whole or in part.
 Product shall not be used for or incorporated into any products or systems whose manufacture, use, or sale is prohibited under any
applicable laws or regulations.
 The information contained herein is presented only as guidance for Product use. No responsibility is assumed by TOSHIBA for any
infringement of patents or any other intellectual property rights of third parties that may result from the use of Product. No license to
any intellectual property right is granted by this document, whether express or implied, by estoppel or otherwise.
 ABSENT A WRITTEN SIGNED AGREEMENT, EXCEPT AS PROVIDED IN THE RELEVANT TERMS AND CONDITIONS OF SALE
FOR PRODUCT, AND TO THE MAXIMUM EXTENT ALLOWABLE BY LAW, TOSHIBA (1) ASSUMES NO LIABILITY
WHATSOEVER, INCLUDING WITHOUT LIMITATION, INDIRECT, CONSEQUENTIAL, SPECIAL, OR INCIDENTAL DAMAGES OR
LOSS, INCLUDING WITHOUT LIMITATION, LOSS OF PROFITS, LOSS OF OPPORTUNITIES, BUSINESS INTERRUPTION AND
LOSS OF DATA, AND (2) DISCLAIMS ANY AND ALL EXPRESS OR IMPLIED WARRANTIES AND CONDITIONS RELATED TO
SALE, USE OF PRODUCT, OR INFORMATION, INCLUDING WARRANTIES OR CONDITIONS OF MERCHANTABILITY, FITNESS
FOR A PARTICULAR PURPOSE, ACCURACY OF INFORMATION, OR NONINFRINGEMENT.
 Do not use or otherwise make available Product or related software or technology for any military purposes, including without limitation,
for the design, development, use, stockpiling or manufacturing of nuclear, chemical, or biological weapons or missile technology
products (mass destruction weapons). Product and related software and technology may be controlled under the Japanese Foreign
Exchange and Foreign Trade Law and the U.S. Export Administration Regulations. Export and re-export of Product or related software
or technology are strictly prohibited except in compliance with all applicable export laws and regulations.
 Please contact your TOSHIBA sales representative for details as to environmental matters such as the RoHS compatibility of Product.
Please use Product in compliance with all applicable laws and regulations that regulate the inclusion or use of controlled substances,
including without limitation, the EU RoHS Directive. TOSHIBA assumes no liability for damages or losses occurring as a result of
noncompliance with applicable laws and regulations.
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2011-10-03