UNISONIC TECHNOLOGIES CO., LTD
UCS1201
Preliminary
LINEAR INTEGRATED CIRCUIT
LOW VOLTAGE
SYNCHRONOUS BUCK
CONTROLLER
DESCRIPTION
The UTC
UCS1201
is a low voltage buck controller. It
provides the control for a DC-DC power solution producing an
output voltage as low as 0.980V over a wide current range. The
UTC
UCS1201
operates at a default switching frequency of
200kHz, but switching frequency is user-programmable with an
additional resistor between R
OSC
and ground. This device
provides undervoltage lockout protection, soft-start, and is
assembled in an SOP-8 package.
SOP-8
FEATURES
* 0.980V±1.0% reference voltage
* 200ns transient response
* soft-start
* 200kHz oscillator frequency (No external resistor required)
* UVLO
* OVP through synchronous MOSFETs
* Synchronous N-Channel buck design
ORDERING INFORMATION
Ordering Number
Lead Free
UCS1201L-S08-R
UCS1201L-S08-T
Halogen Free
UCS1201G-S08-R
UCS1201G-S08-T
Package
SOP-8
SOP-8
Packing
Tape Reel
Tube
www.unisonic.com.tw
Copyright © 2013 Unisonic Technologies Co., Ltd
1 of 5
QW-R103-066.a
UCS1201
PIN CONFIGURATION
Preliminary
LINEAR INTEGRATED CIRCUIT
PIN DESCRIPTION
PIN NO.
1
2
3
4
5
6
7
8
PIN NAME
V
CC
R
OSC
NC
COMP
GATE(H)
GATE(L)
V
FB
GND
DESCRIPTION
Power supply input.
Frequency adjust pin.
No connect.
Error amp output.
High-side switch FET driver pin.
Low-side synchronous FET driver pin.
Feedback voltage
Ground
BLOCK DIAGRAM
V
CC
-
+
+
- 8.5V/7.5V
COMP
-
+
+
- 0.25V
Error Amp
V
FB
-
+
+
- 0.98V
-
PWM Comp
Driver
Latch
GATE(L)
NC
-
0.465V
+
GND
Σ
Oscillator
200kHz
Frequency
Adjust
R
OSC
GATE(H)
UVLO
Latch
+
UNISONIC TECHNOLOGIES CO., LTD
www.unisonic.com.tw
2 of 5
QW-R103-066.a
UCS1201
Preliminary
LINEAR INTEGRATED CIRCUIT
ABSOLUTE MAXIMUM RATING
PARAMETER
SYMBOL
RATINGS
UNIT
Operating Junction Temperature
T
J
150
°C
Storage Temperature Range
T
STG
-65~150
°C
Notes: Absolute maximum ratings are those values beyond which the device could be permanently damaged.
Absolute maximum ratings are stress ratings only and functional device operation is not implied.
THERMAL DATA
PARAMETER
Junction to Ambient
Junction to Case
SYMBOL
θ
JA
θ
JC
RATINGS
165
48
UNIT
°С/W
°С/W
MAXIMUM RATING
PARAMETER
IC Power Input
Compensation Capacitor
Voltage Feedback Input
Frequency Adjust
High-Side FET Driver
Low-Side FET Driver
Ground
SYMBOL
V
CC
COMP
V
FB
R
OSC
GATE(H)
GATE(L)
GND
V
MAX
20V
6.0V
6.0V
6.0V
20V
20V
0.5V
V
MIN
-0.5V
-0.5V
-0.5V
-0.5V
-0.5V, -2.0V
for 50ns
-0.5V, -2.0V
for 50ns
-0.5V
I
SOURCE
N/A
10mA
1.0mA
1.0mA
1.5A Peak,
200mA DC
1.5A Peak,
200mA DC
1.5A Peak,
450mA DC
I
SINK
1.5A Peak,
450mA DC
10mA
1.0mA
1.0mA
1.5A Peak,
200mA DC
1.5A Peak,
200mA DC
N/A
UNISONIC TECHNOLOGIES CO., LTD
www.unisonic.com.tw
3 of 5
QW-R103-066.a
UCS1201
Preliminary
LINEAR INTEGRATED CIRCUIT
ELECTRICAL CHARACTERISTICS
(0°C<T
J
<125°C, 9.0V<V
CC
<20V, C
GATE(H)
=C
GATE(L)
=3.3nF, C
COMP
=0.1μF, R
OSC
=74kΩ, unless otherwise specified.)
(Note 1)
PARAMETER
SYMBOL
TEST CONDITIONS
MIN
TYP
MAX UNIT
Error Amplifier
V
FB
Bias Current
I
FB
V
FB
=0V
0.4
2.0
μA
COMP Source Current
I
SOURCE
COMP=1.5V, V
FB
=0.8V
15
30
60
μA
COMP Sink Current
I
SINK
COMP=1.5V, V
FB
=1.2V
15
30
60
μA
COMP=V
FB
0.970 0.980 0.990
V
Reference Voltage
V
REF
T
J
<25°C
0.965 0.980 0.995
V
COMP Max Voltage
V
COMP-MAX
V
FB
=0.8V
2.4
3.1
V
COMP Min Voltage
V
COMP-MIN
V
FB
=1.2V
0.1
0.2
V
COMP Fault Discharge
I
CHARGE
COMP=1.2V, V
CC
=6.9V
0.5
1.2
mA
Current at UVLO
COMP Fault Discharge
V
RESET
0.1
0.25
0.3
V
Threshold to Reset UVLO
GATE(H) and GATE(L)
Rise Time
t
R
1.0V<GATE(L), GATE(H)<V
CC
-2.0V, V
CC
=12V
40
80
ns
Fall Time
t
F
V
CC
-2.0V<GATE(L), GATE(H)<1.0V, V
CC
=12V
40
80
ns
GATE(H) to GATE(L)
t
DH
GATE(H)<2.0V, GATE(L)>2.0V
40
60
105
ns
Delay
GATE(L) to GATE(H)
t
DL
GATE(L)<2.0V, GATE(H)>2.0V
40
60
105
ns
Delay
Minimum Pulse Width
t
PULSE
GATE(X)=4.0V
250
ns
Measure GATE(L) or GATE(H)
V
CC
-0.5 V
CC
High Voltage (AC)
V
H
V
0.5nF<C
GATE(H)
=C
GATE(L)
<10nF, (Note 2)
Measure GATE(L) or GATE(H)
0
0.5
V
Low Voltage (AC)
V
L
0.5nF<C
GATE(H)
=C
GATE(L)
<10nF, (Note 2)
PWM Comparator
V
FB
=0V, Increase COMP Until GATE(H) Starts
0.415 0.465 0.525
V
PWM Comparator Offset V
PWM-MIN
Switching
Ramp Max Duty Cycle
80
%
Artificial Ramp
Duty Cycle=50%, R
OSC
=74kΩ
50
63
75
mV
Transient Response
COMP=1.5V, V
FB
20mV Overdrive. (Note 2)
200
300
ns
V
FB
Input Range
(Note 3)
0
1.4
V
Oscillator
170
200
230
kHz
F
OSC
R
OSC
Not Used
Switching Frequency
F
OSC
R
OSC
=74kΩ
240
280
320
kHz
General Electrical Specifications
V
CC
Supply Current
I
Q
COMP=0V (No Switching)
9.0
12
mA
Start Threshold
GATE(H) Switching, COMP Charging
8.0
8.5
9.0
V
Stop Threshold
GATE(H) Not Switching, COMP Discharging
7.0
7.5
8.0
V
Hysteresis
V
HYS
Start-Stop
0.75
1.0
1.25
V
Notes:1.Characteristics at temperature extremes are guaranteed via correlation using quality statistical control
methods.
2.Guaranteed by design. Not tested in production.
UNISONIC TECHNOLOGIES CO., LTD
www.unisonic.com.tw
4 of 5
QW-R103-066.a
UCS1201
12V
D3
BAS20HT1
D2
BAV99LT1
C11
0.1µF
U1
C4
1.0µF
R3
Opition
Preliminary
LINEAR INTEGRATED CIRCUIT
TYPICAL APPLICATION CIRCUIT
L1
1.0µH
C1 +
1000µF/16V
+
C2
1000µF/16V
C3
0.1µF
R1
470
Q3
MMBT3904LT1
D1
18V Zener
BZX84C18V
V
CC
R
OSC
NC
COMP
C11
0.1µF
GND
V
FB
GATE(L)
GATE(H)
C9 0.01µF
Q1
UT60N03
L2
4.7µH
Q2
UT110N03
1000µF*2
+
2.5V/10A
UTC UCS1201
104
R5
3.32k
0.98V
R6
5.11k
C10
4700pF
5V
12V
33µF
UT65N03
1.4µH
UTC UCS1201
V
CC
R
OSC
NC
COMP
option
0.1µF
0.1µF
GND
V
FB
GATE(L)
GATE(H)
1000pF
UT65N03
2.26k
1.2V/10A
56µF
10k
UTC assumes no responsibility for equipment failures that result from using products at values that
exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or
other parameters) listed in products specifications of any and all UTC products described or contained
herein. UTC products are not designed for use in life support appliances, devices or systems where
malfunction of these products can be reasonably expected to result in personal injury. Reproduction in
whole or in part is prohibited without the prior written consent of the copyright owner. The information
presented in this document does not form part of any quotation or contract, is believed to be accurate
and reliable and may be changed without notice.
UNISONIC TECHNOLOGIES CO., LTD
www.unisonic.com.tw
5 of 5
QW-R103-066.a