Texas Instruments UCC39413PWTR, UCC39413PW, UCC39413N, UCC39413DTR, UCC39413D Datasheet

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UCC19411/2/3 UCC29411/2/3 UCC39411/2/3
PRELIMINARY
DESCRIPTION
The UCC39411 family of low input voltage, single inductor boost converters is optimized to operate from a single or dual alkaline cell, and steps up to a 3.3V, 5V, or adjustable output at 200mW. The UCC39411 family also provides an auxiliary 7V output, primarily for the gate drive supply, which can be used for applications requiring an auxiliary output, such as 5V, by linear regulating. The primary output will start up under full load at input voltages typically as low as 0.8V with a guaranteed max of 1V, and will operate down to 0.5V once the converter is operating, maximizing battery utilization.
The UCC39411 family is designed to accommodate demanding applications such as pagers and cell phones that require high efficiency over a wide operating range of several milli-watts to a couple of hundred milli-watts. High efficiency at low output current is achieved by optimizing switching and conduction losses with a low total quiescent current (50µA). At higher output current the 0.5switch, and 1.2synchronous rectifier along with continuous mode conduction provide high power efficiency. The wide input voltage range of the UCC39411 family can accommodate other power sources such as NiCd and NimH.
The 39411 family also provides shutdown control. Packages available are the 8 pin SOIC (D), 8 pin DIP (N or J), and 8 pin TSSOP (PW) to optimize board space.
Low Power Synchronous Boost Converter
FEATURES
1V Input Voltage Operation Start-up Guaranteed under FULL Load on Main Output, and Operation Down to
0.5V
200mW Output Power at Battery Voltages as low as 0.8V
Secondary 7V Supply from a Single Inductor
Output Fully Disconnected in Shutdown
Adaptive Current Mode Control for Optimum Efficiency
High Efficiency over Wide Operating Range
6µA Shutdown Supply Current
Output Reset Function with
Programmable Reset Period
SLUS245A - MARCH 1999
1
4
7
6
VOUT
GND
3.3V 200mW
5
C
T
R
RES
3
100µF
RESET CONTROL CIRCUIT
GLITCH SUPRESSION PROGRAMMABLE TIMING
MODULATOR CONTROL CIRCUIT
SYNCHRONOUS RECTIFICATION CIRCUITRY ANTI-CROSS CONDUCTION START-UP MULTIPLEXING LOGIC MAX INPUT POWER CONTROL ADAPTIVE CURRENT CONTROL
START-UP
CIRCUITRY
1.2
CT
RESB
2SD/FB
100µF
VIN
SW
8
VGD
0.5
100µF
1V TO 3.5V
22µH
+
SIMPIFIED BLOCK DIAGRAM AND APPLICATION CIRCUIT (UCC39412)
UDG-98067
Note: Pinout shown is for the TSSOP Package. Consult Package Descriptions for DIP and SOIC configurations.
application
INFO
available
2
UCC19411/2/3 UCC29411/2/3 UCC39411/2/3
DIL-8, SOIC-8 (TOP VIEW) N or J Package, D Package
ABSOLUTE MAXIMUM RATINGS
VIN Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3V to 10V
SD Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3V to V
IN
VGD Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3V to 14V
SW Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3V to 15V
Currents are positive into, negative out of the specific terminal. Consult Packaging Section of the Databook for thermal limita
-
tions and considerations of packages.
CT
GND
SW
RESB
1
2
3
4
8
7
6
5
VGD
VOUT
VIN
SD/FB
CONNECTION DIAGRAMS
ELECTRICAL CHARACTERISTICS:
TJ= 0°C to +70°C for the UCC39411/2/3, TJ= –40°C to +85°C for the
UCC29411/2/3, T
J
= –55C to +125°C for the UCC19411/2/3, VIN= 1.25V for UCC39411/2, VIN= 2.5V for the UCC39413, TA=TJ.
UCC39411 UCC39412 UCC39413
UCC19411/2/3 UCC29411/2/3
PARAMETER TEST CONDITIONS MIN TYP MAX MIN TYP MAX UNITS
VIN Section
Minimum Start-up Voltage No External VGD Load, T
J
=25°C,
I
OUT
=60mA (Note 1)
0.8 1 .08 1 V
No External VGD Load, I
OUT
=60mA
(Note 1)
0.9 1.1 1.2 1.4 V
Minimum Dropout Voltage No External VGD Load, I
OUT
=10mA
(Note 1)
0.5 0.7 V
Input Voltage Range 1.1 3.2 1.3 3.2 V
Quiescent Supply Current (Note 2) 6 12 8 16
µA
Supply Current at Shutdown SD = GND 6 12 8 16
µA
SW
VOUT
VGD
GND
1
2
3
4
8
7
6
5
SD/FB
VIN
RESB
CT
TSSOP-8 (TOP VIEW) PW Package
3
UCC19411/2/3 UCC29411/2/3 UCC39411/2/3
ELECTRICAL CHARACTERISTICS:
TJ= 0°C to +70°C for the UCC39411/2/3, TJ= –40°C to +85°C for the
UCC29411/2/3, T
J
= –55C to +125°C for the UCC19411/2/3, VIN= 1.25V for UCC39411/2, VIN= 2.5V for the UCC39413, TA=TJ.
UCC39411 UCC39412 UCC39413
UCC19411/2/3 UCC29411/2/3
PARAMETER TEST CONDITIONS MIN TYP MAX MIN TYP MAX UNITS
Output Section
Quiescent Supply Current (Note 2) 15 28 20 37
µA
Supply Current at Shutdown SD = GND 3 6 5 10
µA
Regulation Voltage (UCC39412) 1V < V
IN
< 3V 3.2 3.3 3.39 3.15 3.3 3.45 V
1V < V
IN
< 3V, 0mA<I
OUT
<60mA
(Note 1)
3.17 3.3 3.43 3.11 3.3 3.5 V
Regulation Voltage (UCC39413) 1V < V
IN
< 5V 4.85 5 5.15 4.78 5 5.23 V
1V < V
IN
< 5V, 0mA<I
OUT
<60mA
(Note 1)
4.8 5 5.2 4.71 5 5.3 V
ADJ Voltage (UCC39411) 1V < V
IN
< 3V 1.212 1.25 1.288 1.194 1.25 1.306 V
VGD Output Section
Quiescent Supply Current (Note 2) 20 40 27 55
µA
Supply Current at Shutdown SD = GND 20 40 27 55
µA
Regulation Voltage (UCC39411/2)
1V < V
IN
< 3V 6.3 7 7.7 6.3 7 7.7 V
1V < V
IN
< 3V, 0mA<I
OUT
<10mA
(Note 1)
6.3 7 7.7 6.3 7 7.7 V
Regulation Voltage (UCC39413) 1V < V
IN
< 5V 7.7 8.5 9.3 7.7 8.5 9.3 V
1V < V
IN
< 5V, 0mA<I
OUT
<10mA
(Note 1)
7.7 8.5 9.3 7.7 8.5 9.3 V
Inductor Charging Section (L=22
µH)
Peak Discontinuous Current Operating Range, L=22.1µH 180 250 300 180 250 300 mA
Peak Continuous Current 385 550 715 385 550 715 mA
Charge Switch RDS
ON
D Package 0.5 0.75 0.6 0.85
Current Limit Delay (Note 1) 50 50 ns
Synchronous Rectifier Section
Rectifier RDS
ON
D Package 1.2 1.8 1.4 2.16
Shutdown Section
Threshold 0.4 0.6 0.8 0.2 0.6 0.9 V
Input Bias Current SD = GND 2 5 15 2 5 15
µA
SD = 1.25V 5 20 20 100 nA
Reset Section
Threshold (UCC39411) 1.08 1.125 1.17 1.07 1.125 1.18 V
Threshold (UCC39412) 2.85 2.97 3.09 2.83 2.97 3.11 V
Threshold (UCC39413) 4.32 4.5 4.68 4.3 4.5 4.7 V
Reset Period C
T
= 0.15µF 113 188 263 94 188 282 ms
V
OUT
to Reset Delay V
OUT
Falling at –1mV/µs (Note 1) 60 60 µs
Sink Current 1 20 1 20 mA
Output Low Voltage I
OUT
= 500µA 0.1 0.1 V
Output Leakage 0.5 0.5
µA
Note 1 : Guaranteed by design and alternate test methods. Not 100% tested in production. Note 2: For the UCC39411 FB=1.306V, VGD=7.7V, For the UCC39412 V
OUT
=3.5V and VGD=7.7V, For the UCC39413
V
OUT
=5.3V, VGD=9.3V.
4
UCC19411/2/3 UCC29411/2/3 UCC39411/2/3
PIN DESCRIPTIONS
VIN: Input Voltage to supply the IC during start-up. After
the output is running the IC draws power from VOUT or VGD.
SW: An inductor is connected between this node and VIN. The VGD (Gate Drive Supply) flyback diode is also connected to this pin. When servicing the main output supply this pin will pull low charging the inductor, then shut off dumping the energy through the synchronous rectifier to the output. When servicing the VGD supply the internal synchronous rectifier stays off and the en
­ergy is diverted to VGD through the flyback diode. During discontinuous portions of the inductor current, a MOS
­FET resistively connects VIN to SW damping excess cir
­culating energy to eliminate undesired high frequency ringing.
VGD: The VGD pin which is coarsely regulated around 7V (8.5V for the UCC39413) is primarily used for the gate drive supply for the power switches in the IC. This pin can be loaded with up to 10mA as long as it does not present a load at voltages below 2V (this ensures proper start-up of the IC). The VGD supply can go as low as
6.3V without interfering with the servicing of the main output. Below 6.3V, VGD will have the highest priority.
VOUT: Main output voltage (3.3V, 5V, or adjustable) which has highest priority in the multiplexing scheme, as long as VGD is above the critical level of 6.3V. Startup at full load is achievable at input voltages down to 1V.
CT: This pin provides the timer for determining the reset period. The period is controlled by placing a capacitor to ground of value C = (0.81e
-6
)T where T is the desired
reset period.
RESB: This pin provides an active low signal to alert the user when the main output voltage falls below 10% of its targeted value. The open drain output can be used to re
­set a microcontroller which may be powered off of the main output voltage.
SD/FB: For the UCC39411, this pin is used to adjust the output voltage via a resistive divider from VOUT. It also serves as the shutdown pin for all three versions. Pulling this pin low provides a shutdown signal to the IC.
GND: Ground of the IC.
APPLICATION INFORMATION
Operation
A detailed block diagram of the UCC39411 is shown in Figure 1. Unique control circuitry provides high efficiency power conversion for both light and heavy loads by tran
-
sitioning between discontinuous and continuous conduc
­tion based on load conditions. Figure 2 depicts converter waveforms for the application circuit shown in Figure 3. A single 22µH inductor provides the energy pulses required for a highly efficient 3.3V converter at up to 200mW output power
At time t1 the 3.3V output voltage has dropped below its lower threshold, and the inductor is charged with an on time determined by: T
ON
= 5.5µs/VIN. For a 1.25V input
anda22µH inductor, the resulting peak current is ap
­proximately 250mA. At time t2, the inductor begins to discharge with a minimum off time of approximately 1µs. Under lightly loaded conditions, the amount of energy delivered in this single pulse would satisfy the voltage control loop, and the converter would not command any more energy pulses until the output again drops below the lower voltage threshold
At time t3 the VGD supply drops below its lower thresh
­old, but the output voltage is still above its threshold point. This results in an energy pulse to the gate drive supply at t4. In some cases, a single pulse supplied to
VGD is insufficient to raise the VGD voltage level enough to satisfy the voltage loop. Under this condition, multiple pulses will be supplied to VGD. Note: when the UCC39411/2/3 is servicing VGD only, the IC will maintain a discontinuous mode of operation. After time t4, the
3.3V output drops below its threshold and requests to be serviced once the VGD cycle has completed, which oc
-
curs at time t5.
Time t6 represents a transition between light load and heavy load. A single energy pulse is not sufficient to force the output voltage above its upper threshold before the minimum off time has expired and a second charge cycle is commanded. Since the inductor current does not reach zero in this case, the peak current is greater than 250mA at the end of the next charge on time. The result is a ratcheting of inductor current until either the output voltage is satisfied, or the converter reaches its set current limit. At time t7, the gate drive voltage has dropped below its 7V threshold but the converter contin
­ues to service the output because it has higher priority unless VGD drops below 6.3V
Between time t7 and t8, the converter reaches its peak current limit.
Once the peak current is reached, the converter oper
­ates in continuous mode with approximately 60mA of in
-
5
UCC19411/2/3 UCC29411/2/3 UCC39411/2/3
1
3
VGD
SD/FB
VOUT
0.5V
VGD
8
RESET
4
5
2
200kHZ
START-UP
OSCILLATOR
AND
CONTROL
VLOW
SW
1.25V (UCC39411)
3.3V (UCC39412)
5.0V (UCC39413)
PRIORITY
ENCODER
VGD
7.5V (UCC39411/2)
8.5V (UCC39413)
VGD
6V (UCC39411/2)
7.5V (UCC39413)
SD
CLK
D
Q
FROM SD
VREF GOOD
1µS RISING
EDGE DELAY
R
S
D
Q
R
S
D
Q
1µS
R.E.D.
VON
INTERNAL
BIAS
1.25
REFERENCE
2.5V
VGD
VDD
RESET
TIMER
CT
6
CT
5V
GS
VREF
GOOD
FROM SD
RISING EDGE
DELAY
T
ON
=5.5E
-6
VBAT
50nS
R.E.D.
0.66A
MAX
C
PUMP
VBAT
T
OFF
TIMER
50nS
R.E.D.
VON
VIN
VBAT VGD
VGD
1.2
VOUT
7
Figure 1. Low power synchronous boost.
Notes: Switches are shown in the low state.
Pinout as shown is for the 8 pin D, N or J. See Package Descriptions for 8 pin SOIC.
APPLICATION INFORMATION (continued)
UDG-98068
6
UCC19411/2/3 UCC29411/2/3 UCC39411/2/3
3
4
1
8
GND
L=10µHTO 100µH
7
R1
100µF
6SD/FB
10µF
VIN SW
2VGD
10µF
1-2 CELL ALKALINE
1.0V TO 3.2V
5
80nF
100k
V
OUT
CT
RESET
R2
VOUT
Note: Shown pinout is for the TSSOP package. See Package Descriptions for DIP and SOIC pinouts.
Figure 3. Low power synchronous boost converter ADJ version –200mW.
VGD
RIPPLE
50mV/DIV
7V
t1 t2 t3 t4 t5 t6 t7 t8 t9
INDUCTOR
CURRENT
CURRENT LIMIT
OUTPUT
RIPPLE
20mV/DIV
3.3V
HIGH LOAD CURRENTLIGHT LOAD CURRENT
80mV P–P TYPICAL
20mV P–P TYPICAL
Figure 2. Inductor current and output ripple waveforms.
APPLICATION INFORMATION (continued)
UDG-98069
UDG-98070
7
UCC19411/2/3 UCC29411/2/3 UCC39411/2/3
ductor current ripple. At time t8, the 3.3V output is satisfied and the converter can service the gate drive voltage, VGD, which occurs at time t9
Shutdown Control
Shutdown of the UCC39411/2/3 is controlled via inter
­face with the SD/FB pin. Pulling the SD/FB pin low, for all versions, causes the IC to go into shutdown. In the UCC39412/3, the SD/FB pin is used solely as a shut
­down function. Therefore, the SD/FB pin for the UCC39412 and UCC39413 can be directly controlled us
­ing conventional CMOS or TTL technology. For the UCC39411, interface into the SD/FB is slightly more complicated due to the added feedback function. When feeding back the output voltage to the SD/FB pin on the UCC39411, the IC requires a thevenin impedance of at least 200k(500kfor industrial/military applications) to ground. Then, to accomplish shutdown of the IC, an open drain device may be used.
Component Selection Inductor Selection
An inductor value of 22µH will work well in most applica­tions, but values between 10µHto100µH are also ac- ceptable. Lower value inductors typically offer lower ESR and smaller physical size. Due to the nature of the “bang-bang” controllers, larger inductor values will typi­cally result in larger overall voltage ripple, because once the output voltage level is satisfied the converter goes discontinuous, resulting in the residual energy of the in­ductor causing overshoot.
It is recommended to keep the ESR of the inductor below
0.15for 200mW applications. A Coilcraft DT3316P-223 surface mount inductor is one choice since it has a cur
­rent rating of 1.5A and an ESR of 84m.
Other choices for surface mount inductors are shown in Table 1.
Output Capacitor Selection
Once the inductor value is selected the capacitor value will determine the ripple of the converter. The worst case peak to peak ripple of a cycle is determined by two com
­ponents, one is due to the charge storage characteristic, and the other is the ESR of the capacitor. The worst case ripple occurs when the inductor is operating at max current and is expressed as follows:
()
()
V
IL
CV V
IC
CL
OI
CL ESR
=
+
2
2
I
CL
= the peak inductor current = 550mA
V= Output ripple
V
O
= Output Voltage
V
I
= Input Voltage
C
ESR
= ESR of the output capacitor.
A Sanyo OS-CON series surface mount capacitor (10SN100M) is one recommendation. This part has an ESR rating of 90mat 100µF .
Other potential capacitor sources are shown in Table 2.
Input Capacitor Selection
Since the UCC39411 family does not require a large de
­coupling capacitor on the input voltage to operate prop
­erly, a 10µF cap is sufficient for most applications. Optimum efficiency will occur when the capacitor value is large enough to decouple the source impedance, this usually occurs for capacitor values in excess of 100µF.
APPLICATION INFORMATION (continued)
MANUFACTURER PART NUMBER
Sanyo Video Components
OS-CON Series
San Diego, California Tel: 619-661-6322 Fax: 619-661-1055 AVX TPS Series Sanford, Maine Tel: 207-282-5111 Fax: 207-283-1941 Sprague 695D Series Concord, New Hampshire Tel: 603-224-1961
Table 2. Capacitor Suppliers
MANUFACTURER PART NUMBERS
Coilcraft DT Series
Cary, Illinois Tel: 708-639-2361 Fax: 708-639-1469 Coiltronics CTX Series Boca Raton, Florida Tel: 407-241-7876
Table 1. Inductor Suppliers
8
UCC19411/2/3 UCC29411/2/3 UCC39411/2/3
UNITRODE CORPORATION 7 CONTINENTAL BLVD. • MERRIMACK, NH 03054 TEL. (603) 424-2410 • FAX (603) 424-3460
TYPICAL CHARACTERISTICS
Figure 4. Percent Efficiency at VIN= 1.0, V
OUT
= 3.3V Figure 6. Percent Efficiency at VIN= 2.5, V
OUT
= 3.3V
Figure 5. Percent Efficiency at VIN= 1.25, V
OUT
= 3.3V Figure 7. Percent Efficiency at VIN= 3.3, V
OUT
= 3.3V
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