TS2596
3A / 150KHz Buck Dc-Dc Converter
1/9
Version: E13
TO
-
220
-
5L
TO
-
263
-
5L
(D
2
PAK)
General Description
The TS2596 Series are step-down switching regulators with all required active functions. It is capable of driving
3A load with excellent line and load regulations. These devices are available in fixed output voltages of 3.3V, 5V,
and an adjustable output version.
The TS2596 series operates at a switching frequency of 150kHz thus allowing smaller sized filter components
than what would be needed with lower frequency switching regulators. It substantially not only reduces the area of
board size but also the size of heat sink, and in some cases no heat sink is required. The ±4% tolerance on output
voltage within specified input voltages and output load conditions is guaranteed. Also, the oscillator frequency
accuracy is within ±10%. External shutdown is included. Featuring 100µA (typical) standby current. The output
switch includes cycle-by-cycle current limiting, as well as thermal shutdown for full protection under fault
conditions.
Features
● Output Voltage: 3.3V, 5V & Adjustable version
● Adjustable Output Voltage Range 1.23V~38.5V
● 150KHz fixed switching frequency
● Voltage Mode Non-synchronous PWM control
● Thermal Shutdown and Current Limit Protection
● ON/OFF Shutdown Control Input
● High Efficiency
● Short Circuit Protect (SCP)
● Operating Voltage Can be up to 40V
● Output Load Current 3A
● Low Power Standby Mode
● Built-in switching transistor on chip
Ordering Information
Part No. Package
Packing
TS2596CZ5xx C0 TO-220-5L
50pcs / Tube
TS2596CM5xx RN
TO-263-5L
800pcs / 13” Reel
Note: Where xx denotes voltage option, available are
50= 5.0V
33= 3.3V
Leave blank for adjustable version
Application
● Simple High-efficiency Step down Regulator
● On-Card Switching Regulators
● Positive to Negative Converter
Absolute Maximum Rating
Parameter Symbol Limit Unit
Maximum Supply Voltage V
CC
+45 V
Recommend Operating Supply Voltage V
OP
+4.5 to +40 V
SW, EN Pin Input Voltage V
SW
, V
EN
-0.3 to +40 V
Feedback Pin Voltage V
FB
-0.3 to +12 V
Power Dissipation P
D
Internally Limited W
Output Voltage to Ground V
OUT
-1 V
Storage Temperature Range T
ST
-65 to +150
o
C
Operating Temperature Range T
OP
-40 to +125
o
C
ESD Susceptibility (HBM) 2 kV
Pin
Definition
:
1. Input
2. SW Output
3. Ground
4. Feedback
5. Enable
TS2596
3A / 150KHz Buck Dc-Dc Converter
2/9
Version: E13
Thermal Information
Parameter Symbol Maximum Unit
Thermal Resistance* (Junction to Case)
TO-220-5L
Ө
JC
2
o
C/W
TO-263-5L
2
Thermal Resistance* (Junction to Ambient)
TO-220-5L
Ө
JA
50
o
C/W
TO-263-5L
50
Note: Ө
JA
is measured with the PCB copper area (need connect to GROUND pins) of approximately 1.5 in
2
(Multi-
layer)
Electrical Specifications (All Output Voltage Version)
(Ta = 25
o
C unless otherwise noted, V
IN
=12V for 3.3V, 5V, Adjustable version. I
LOAD
=0.3A)
Parameter Symbol
Test Condition Min
Typ
Max
Unit
Output Feedback ADJ V
FB
4.5V≤ V
IN
≤40V
0.2A≤ I
LOAD
≤3A 1.180
1.23
1.280
V
Efficiency η V
IN
=12V, I
LOAD
=3A, V
OUT
=5V -- 77 -- %
Output Feedback 3.3V V
FB
4.75V≤ V
IN
≤40V
0.2A≤ I
LOAD
≤3A 3.135
3.3V
3.465
V
Efficiency η V
IN
=12V, I
LOAD
=3A -- 75 -- %
Output Feedback 5V V
FB
7V≤ V
IN
≤40V
0.2A≤ I
LOAD
≤3A 4.75
5 5.25
V
Efficiency η V
IN
=12V, I
LOAD
=3A -- 80 -- %
Feedback Bias Current I
FB
V
FB
=1.3V (Adj version only) -- 10 100 nA
Oscillator Frequency F
OSC
127 150 173 KHz
Soft-Start Time T
SS
Rising edge of EN on to I
CL
-- 3 -- mS
Current Limit I
CL
Pear Current, no outside circuit
V
FB
=0V force driver on 3.3 -- -- A
Oscillator Frequency of Short Circu
it
Protect F
SCP
When current limit occurred and
V
FB
<0.5V, Ta = 25
o
C 110 150 173 KHz
Saturation Voltage V
SAT
I
OUT
=3A, No outside circuit
V
FB
=0V force driver on -- 1.15
1.50
V
ON/OFF Pin Logic Input Threshold
Voltage V
IL
Low (regulator ON) -- 1.3 0.6 V
V
IH
High (regulator OFF) 2.0 --
ON/OFF Pin Logic Input Current I
H
V
LOGIC
=2.5V (OFF) -- 5 15 µA
I
L
V
LOGIC
=0.5V (ON) -- 0.02
5
Maximum Duty Cycle (ON) DC V
FB
=0V force driver on -- 100 -- %
Maximum Duty Cycle (OFF) V
FB
=12V force driver off -- 0 --
Quiescent Current I
Q
V
FB
=12V force driver off -- 5 10 mA
Standby Quiescent Current I
STBY
ON/OFF pin=5V -- 80 200 µA
V
IN
=40V 250
SW Pin Leakage
Current SW pin = 0 I
SWL
No outside circuit,
V
FB
=12V force driver off -- 0.3 2 mA
SW pin = -1 V
IN
=12V -- 7.5 30 mA
TS2596
3A / 150KHz Buck Dc-Dc Converter
3/9
Version: E13
Block Diagram
Typical Application Circuit
1. Adjustable Output Voltage Version
VIN=12V
C2
0.1uF D1
B340A
L1
33uH
1 2
C3
470uF
C1
470uF
U1
1
23
4
5
Vcc
SW
FB
EN
Vss
Vout=5.0V/3AVIN=12V
ON/OFF
C6
0.1uF R2
1.5K
R1
4.7K
VIN=24V
C2
0.1uF D1
B340A
L1
47uH
1 2
C3
470uF
C1
470uF
U1
1
23
4
5
Vcc
SW
FB
EN
Vss
Vout=5.0V/3AVIN=24V
C6
0.1uF R2
1.5K
R1
4.7K
V
OUT
= V
FB
×
(1 +
R2
R1
), V
FB
= 1.23V, R2 = 0.7K ~ 3K
V
OUT
R2 R1
5.0V 1.5K 4.7K
3.3V 1.5K 2.5K
2.5V 1.5K 1.5K
TS2596
3A / 150KHz Buck Dc-Dc Converter
4/9
Version: E13
Typical Application Circuit (Continue)
2. Fixed Output Voltage Version
C2
0.1uF
D1
B340A
L1
47uH
1 2
C3
470uF
C1
470uF
U1
1
23
4
5
Vcc
SW
FB
EN
Vss
Vout=5.0V/3AVIN=24V
C6
0.1uF
L1 recommend value (I
OUT
=3A,)
V
OUT
2.5V 3.3V 5V 12V
V
IN
=12V 33uH 33uH 33~47uH NA
V
IN
=24V 33uH 33uH 47uH 68uH
Pin Function Description
Vcc
This is the positive input supply for the IC switching regulator. A suitable input bypass capacitor must be presented
at this pin to minimize voltage transients and to supply the switching currents needed by the regulator.
Ground
Circuit ground
SW Output
Internal switch. The voltage at this pin switches between (+Vcc – Vsat) and approximately – 0.5V, with a duty cycle
of approximately Vout / Vcc. To minimize coupling to sensitive circuitry, the PC board copper area connected to this
pin should be minimized.
Feedback
Sense the regulated output voltage to complete the feedback loop.
Enable
Allows the switching regulator circuit to be shutdown using logic level signals thus dropping the total input supply
current to approximately 100uA. Pulling this pin below a threshold voltage of approximately 1.3V turns the regulator
on, and pulling this pin above 1.3V (up to a maximum of Vcc) shuts the regulator down. If this shutdown feature is
not needed, the EN pin can be wired to the ground pin.
Thermal Considerations
The TS2596 is available in two packages, a TO-220-5L and TO-263-5L.
The TO-220-5L package needs a heat sink under most conditions. The size of the heat sink depends on the input
voltage, the output voltage, the load current and the ambient temperature. The TS2596 junction temperature rises
above ambient temperature for a 3A load and different input and output voltages. The data for these curves was
taken with the TS2596 (TO-220-5L package) operating as a buck switching regulator in an ambient temperature of
25
o
C (still air). These temperature rise numbers are all approximate and there are many factors that can affect
these temperatures. Higher ambient temperatures require more heat sinking.
The TO-263-5L surface mount package tab is designed to be soldered to the copper on a printed circuit board. The
copper and the board are the heat sink for this package and the other heat producing components, such as the
catch diode and inductor. The PC board copper area that the package is soldered to should be at least 0.8 in
2
, and
ideally should have 2 or more square inches of 2 oz. Additional copper area improves the thermal characteristics,
TS2596
3A / 150KHz Buck Dc-Dc Converter
5/9
Version: E13
Pin Function Description (Continue)
Thermal Considerations
but with copper areas greater than approximately 6 in
2
, only small improvements in heat dissipation are realized. If
further thermal improvements are needed, double sided, multilayer PC board with large copper areas and/or airflow
are recommended.
The TS2596 (TO-263-5L package) junction temperature rise above ambient temperature with a 3A load for various
input and output voltages. This data was taken with the circuit operating as a buck switching regulator with all
components mounted on a PC board to simulate the junction temperature under actual operating conditions. This
curve can be used for a quick check for the approximate junction temperature for various conditions, but be aware
that there are many factors that can affect the junction temperature. When load currents higher than 3A are used,
double sided or multilayer PC boards with large copper areas and/or airflow might be needed, especially for high
ambient temperatures and high output voltages.
For the best thermal performance, wide copper traces and generous amounts of printed circuit board copper
should be used in the board layout. (Once exception to this is the output (switch) pin, which should not have large
areas of copper.) Large areas of copper provide the best transfer of heat (lower thermal resistance) to the
surrounding air, and moving air lowers the thermal resistance even further.
TS2596
3A / 150KHz Buck Dc-Dc Converter
6/9
Version: E13
Electrical Characteristics Curve
Figure 1. Output Ripple
(V
IN
=12V, V
OUT
=5V, I
O
=3A)
Figure 2. Power On Test Wave
(V
IN
=12V, V
OUT
=5V, I
O
=3A)
Figure 3. Load Transient Response
(V
IN
=12V, V
OUT
=5V, I
O
=0.2~3A)
Figure 4. EN On Test Wave
(V
IN
=12V, V
OUT
=5V, I
O
=3A)
Figure 5. Efficiency
Figure 6. Efficiency
TS2596
3A / 150KHz Buck Dc-Dc Converter
7/9
Version: E13
TO-220-5L Mechanical Drawing
Unit: Millimeters
Marking Diagram
Y
= Year Code
M
= Month Code
(A=Jan, B=Feb, C=Mar, D=Apl, E=May, F=Jun, G=Jul, H=Aug, I=Sep,
J=Oct, K=Nov, L=Dec)
L
= Lot Code
XX
= Voltage Code
(3.3=3.3V, 5.0=5V)
= Package Code for Adjustable type
CZ5 = TO-220-5L
TS2596
3A / 150KHz Buck Dc-Dc Converter
8/9
Version: E13
TO-263-5L Mechanical Drawing
Unit: Millimeters
Marking Diagram
Y
= Year Code
M
= Month Code
(A=Jan, B=Feb, C=Mar, D=Apl, E=May, F=Jun, G=Jul, H=Aug, I=Sep,
J=Oct, K=Nov, L=Dec)
L
= Lot
Code
XX
= Voltage Code
(3.3=3.3V, 5.0=5V)
= Package Code for Adjustable type
CM5 = TO-263-5L)
TS2596
3A / 150KHz Buck Dc-Dc Converter
9/9
Version: E13
Notice
Specifications of the products displayed herein are subject to change without notice. TSC or anyone on its behalf,
assumes no responsibility or liability for any errors or inaccuracies.
Information contained herein is intended to provide a product description only. No license, express or implied, to
any intellectual property rights is granted by this document. Except as provided in TSC’s terms and conditions of
sale for such products, TSC assumes no liability whatsoever, and disclaims any express or implied warranty,
relating to sale and/or use of TSC products including liability or warranties relating to fitness for a particular purpose,
merchantability, or infringement of any patent, copyright, or other intellectual property right.
The products shown herein are not designed for use in medical, life-saving, or life-sustaining applications.
Customers using or selling these products for use in such applications do so at their own risk and agree to fully
indemnify TSC for any damages resulting from such improper use or sale.
