TEXAS INSTRUMENTS TL284xB, TL384xB Technical data
www.ti.com
FEATURES
1
2
3
4
8
7
6
5
COMP
VFB
I
SENSE
RT/C
T
V
REF
V
CC
OUTPUT
GND
D (SOIC) OR P (PDIP) PACKAGE
(TOP VIEW)
1
2
3
4
5
6
7
14
13
12
11
10
9
8
COMP
NC
VFB
NC
I
SENSE
NC
RT/C
T
V
REF
NC
V
CC
VC
OUTPUT
GND
POWER GROUND
D (SOIC) PACKAGE
(TOP VIEW)
NC − No internal connection
• Low Start-Up Current (<0.5 mA)
• Trimmed Oscillator Discharge Current
• Current Mode Operation to 500 kHz
• Automatic Feed-Forward Compensation
• Latching PWM for Cycle-by-Cycle Current
Limiting
• Internally Trimmed Reference With
Undervoltage Lockout
• High-Current Totem-Pole Output Undervoltage
Lockout With Hysteresis
• Double-Pulse Suppression
TL284xB , TL384xB
HIGH-PERFORMANCE CURRENT-MODE PWM CONTROLLERS
SLVS610B – AUGUST 2006 – REVISED JULY 2007
DESCRIPTION/ORDERING INFORMATION
The TL284xB and TL384xB series of control integrated circuits provide the features that are necessary to
implement off-line or dc-to-dc fixed-frequency current-mode control schemes, with a minimum number of
external components. Internally implemented circuits include an undervoltage lockout (UVLO) and a precision
reference that is trimmed for accuracy at the error amplifier input. Other internal circuits include logic to ensure
latched operation, a pulse-width modulation (PWM) comparator that also provides current-limit control, and a
totem-pole output stage designed to source or sink high-peak current. The output stage, suitable for driving
N-channel MOSFETs, is low when it is in the off state.
The TL284xB and TL384xB series are pin compatible with the standard TL284x and TL384x with the following
improvements. The start-up current is specified to be 0.5 mA (max), while the oscillator discharge current is
trimmed to 8.3 mA (typ). In addition, during undervoltage lockout conditions, the output has a maximum
saturation voltage of 1.2 V while sinking 10 mA (V
Major differences between members of these series are the UVLO thresholds and maximum duty-cycle ranges.
Typical UVLO thresholds of 16 V (on) and 10 V (off) on the TLx842B and TLx844B devices make them ideally
suited to off-line applications. The corresponding typical thresholds for the TLx843B and TLx845B devices are
8.4 V (on) and 7.6 V (off). The TLx842B and TLx843B devices can operate to duty cycles approaching 100%. A
duty-cycle range of 0% to 50% is obtained by the TLx844B and TLx845B by the addition of an internal toggle
flip-flop, which blanks the output off every other clock cycle.The TL284xB-series devices are characterized for
operation from –40 ° C to 85 ° C. The TL384xB-series devices are characterized for operation from 0 ° C to 70 ° C.
= 5 V).
CC
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas
Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
Copyright © 2006–2007, Texas Instruments Incorporated
www.ti.com
TL284xB , TL384xB
HIGH-PERFORMANCE CURRENT-MODE PWM CONTROLLERS
SLVS610B – AUGUST 2006 – REVISED JULY 2007
ORDERING INFORMATION
T
A
PDIP – P Tube of 50
SOIC – D (8 pin)
–40 ° C to 85 ° C
SOIC – D (14 pin)
PDIP – P Tube of 50
SOIC – D (8 pin)
0 ° C to 70 ° C
SOIC – D (14 pin)
(1) Package drawings, standard packing quantities, thermal data, symbolization, and PCB design guidelines are available at
www.ti.com/sc/package.
PACKAGE
(1)
Tube of 75 TL2842BD-8
Reel of 2500 TL2842BDR-8
Tube of 75 TL2843BD-8
Reel of 2500 TL2843BDR-8
Tube of 75 TL2844BD-8
Reel of 2500 TL2844BDR-8
Tube of 75 TL2845BD-8
Reel of 2500 TL2845BDR-8
Tube of 75 TL2842BD
Reel of 2500 TL2842BDR
Tube of 75 TL2843BD
Reel of 2500 TL2843BDR
Tube of 75 TL2844BD
Reel of 2500 TL2844BDR
Tube of 75 TL2845BD
Reel of 2500 TL2845BDR
Tube of 75 TL3842BD-8
Reel of 2500 TL3842BDR-8
Tube of 75 TL3843BD-8
Reel of 2500 TL3843BDR-8
Tube of 75 TL3844BD-8
Reel of 2500 TL3844BDR-8
Tube of 75 TL3845BD-8
Reel of 2500 TL3845BDR-8
Tube of 75 TL3842BD
Reel of 2500 TL3842BDR
Tube of 75 TL3843BD
Reel of 2500 TL3843BDR
Tube of 75 TL3844BD
Reel of 2500 TL3844BDR
Tube of 75 TL3845BD
Reel of 2500 TL3845BDR
ORDERABLE PART NUMBER TOP-SIDE MARKING
TL2842BP TL2842BP
TL2843BP TL2843BP
TL2844BP TL2844BP
TL2845BP TL2845BP
2842B
2843B
2844B
2845B
TL2842B
TL2843B
TL2844B
TL2845B
TL3842BP TL3842BP
TL3843BP TL3843BP
TL3844BP TL3844BP
TL3845BP TL3845BP
3842B
3843B
3844B
3845B
TL3842B
TL3843B
TL3844B
TL3845B
2
Submit Documentation Feedback
www.ti.com
Internal
Bias
V
REF
Good
Logic
OSC
Error
Amplifier
PWM
Latch
Current-
Sense
Comparator
34 V NOM
V
CC
GND
RT/C
T
VFB
COMP
I
SENSE
7
5
4
2
1
3
8
6
V
REF
OUTPUT
+
−
UVLO
EN
2R
R 1 V
S
R
T
+
−
5-V V
REF
2.5 V
HIGH-PERFORMANCE CURRENT-MODE PWM CONTROLLERS
FUNCTIONAL BLOCK DIAGRAM
TL284xB , TL384xB
SLVS610B – AUGUST 2006 – REVISED JULY 2007
A. Pin numbers shown are for the 8-pin D package.
Submit Documentation Feedback
3
www.ti.com
TL284xB , TL384xB
HIGH-PERFORMANCE CURRENT-MODE PWM CONTROLLERS
SLVS610B – AUGUST 2006 – REVISED JULY 2007
Absolute Maximum Ratings
over operating free-air temperature range (unless otherwise noted)
V
CC
V
I
I
CC
I
O
I
O(sink)
θ
JA
T
J
T
stg
T
lead
(1) Stresses beyond those listed under "absolute maximum ratings" may cause permanent damage to the device. These are stress ratings
(2) All voltages are with respect to the device GND terminal.
(3) Maximum power dissipation is a function of TJ(max), θJA, and TA. The maximum allowable power dissipation at any allowable ambient
(4) The package thermal impedance is calculated in accordance with JESD 51-7.
Supply voltage V
Analog input voltage range VFB and I
Supply current 30 mA
Output current ± 1 A
Error amplifier output sink current 10 mA
Package thermal impedance
Output energy Capacitive load 5 μ J
Virtual junction temperature 150 ° C
Storage temperature range –65 150 ° C
Lead temperature Soldering, 10 s 300 ° C
only, and functional operation of the device at these or any other conditions beyond those indicated under "recommended operating
conditions" is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
temperature is PD= (TJ(max) – TA)/ θJA. Operating at the absolute maximum TJof 150 ° C can impact reliability.
(1) (2)
MIN MAX UNIT
Low impedance source 30
ICC< 30 mA
SENSE
(3) (4)
D package
8 pin 97
14 pin 86 ° C/W
limiting
–0.3 6.3 V
P package 85
Self
Recommended Operating Conditions
V
V
CC
V
I
V
O
I
CC
I
O
I
O(ref)
f
osc
T
J
Supply voltage V
Input voltage V
Output voltage V
Supply current, externally limited 25 mA
Average output current 200 mA
Reference output current –20 mA
Oscillator frequency 100 500 kHz
Operating free-air temperature ° C
(1) The recommended voltages for VC and POWER GROUND apply only to the 14-pin D package.
CC
(1)
VC
RT/C
T
VFB and I
SENSE
OUTPUT 0 30
POWER GROUND
TL284xB –40 85
TL384xB 0 70
MIN NOM MAX UNIT
30
30
0 5.5
0 5.5
(1)
–0.1 1
4
Submit Documentation Feedback
www.ti.com
HIGH-PERFORMANCE CURRENT-MODE PWM CONTROLLERS
TL284xB , TL384xB
SLVS610B – AUGUST 2006 – REVISED JULY 2007
Reference Section Electrical Characteristics
V
CC
Output voltage IO= 1 mA, TJ= 25 ° C 4.95 5 5.05 4.9 5 5.1 V
Line regulation V
Load regulation IO= 1 mA to 20 mA 6 25 6 25 mV
Average temperature
coefficient of output voltage
Output voltage, worst-case V
variation IO= 1 mA to 20 mA
Output noise voltage f = 10 Hz to 10 kHz, TJ= 25 ° C 50 50 μ V
Output-voltage long-term drift After 1000 h at TJ= 25 ° C 5 25 5 25 mV
Short-circuit output current –30 –100 –180 –30 –100 –180 mA
(1) Adjust V
(2) All typical values are at TJ= 25 ° C.
Oscillator Section
V
CC
Initial accuracy kHz
Voltage stability V
Temperature stability 5 5 %
Amplitude Peak to peak 1.7 1.7 V
Discharge current mA
(1) Output frequency equals oscillator frequency for the TL3842B and TL3843B. Output frequency is one-half the oscillator frequency for the
(2) Adjust V
(3) All typical values are at TJ= 25 ° C.
(1)
= 15 V
, RT= 10 k Ω , CT= 3.3 nF, over recommended operating free-air temperature range (unless otherwise specified)
PARAMETER TEST CONDITIONS UNIT
= 12 V to 25 V 6 20 6 20 mV
CC
TL284xB TL384xB
MIN TYP
(2)
MAX MIN TYP
(2)
0.2 0.4 0.2 0.4 mV/ ° C
= 12 V to 25 V,
CC
above the start threshold before setting it to 15 V.
CC
(1)
Electrical Characteristics
= 15 V
(2)
, RT= 10 k Ω , CT= 3.3 nF, over recommended operating free-air temperature range (unless otherwise specified)
PARAMETER TEST CONDITIONS UNIT
4.9 5.1 4.82 5.18 V
TL284xB TL384xB
MIN TYP
(3)
MAX MIN TYP
(3)
TJ= 25 ° C 49 52 55 49 52 55
TA= T
TJ= 25 ° C, RT= 6.2 k Ω ,
CT= 1 nF
TJ= 25 ° C, RT/C
RT/C
to T
low
high
48 56 48 56
225 250 275 225 250 275
= 12 V to 25 V 0.2 1 0.2 1 %
CC
= 2 V 7.8 8.3 8.8 7.8 8.3 8.8
T
= 2 V 7.5 8.8 7.6 8.8
T
TL3844B and TL3845B.
above the start threshold before setting it to 15 V.
CC
MAX
MAX
Submit Documentation Feedback
5
www.ti.com
TL284xB , TL384xB
HIGH-PERFORMANCE CURRENT-MODE PWM CONTROLLERS
SLVS610B – AUGUST 2006 – REVISED JULY 2007
Error-Amplifier Section Electrical Characteristics
V
CC
Feedback input voltage COMP = 2.5 V 2.45 2.5 2.55 2.42 2.5 2.58 V
Input bias current –0.3 –1 –0.3 –2 μ A
Open-loop voltage
amplification
Gain-bandwidth product 0.7 1 0.7 1 MHz
Supply-voltage rejection ratio V
Output sink current VFB = 2.7 V, COMP = 1.1 V 2 6 2 6 mA
Output source current VFB = 2.3 V, COMP = 5 V –0.5 –0.8 –0.5 –0.8 mA
High-level output voltage 5 6 5 6 V
Low-level output voltage 0.7 1.1 0.7 1.1 V
(1) Adjust V
(2) All typical values are at TJ= 25 ° C.
(1)
= 15 V
, RT= 10 k Ω , CT= 3.3 nF, over recommended operating free-air temperature range (unless otherwise specified)
PARAMETER TEST CONDITIONS UNIT
TL284xB TL384xB
MIN TYP
(2)
MAX MIN TYP
(2)
VO= 2 V to 4 V 65 90 65 90 dB
= 12 V to 25 V 60 70 60 70 dB
CC
VFB = 2.3 V,
RL= 15 k Ω to GND
VFB = 2.7 V,
RL= 15 k Ω to GND
above the start threshold before setting it to 15 V.
CC
MAX
Current-Sense Section Electrical Characteristics
V
CC
Voltage amplification
Current-sense comparator
threshold
Supply-voltage rejection
ratio
Input bias current –2 –10 –2 –10 μ A
Delay time to output VFB = 0 V to 2 V 150 300 150 300 ns
(1) Adjust V
(2) All typical values are at TJ= 25 ° C.
(3) Measured at the trip point of the latch, with VFB at 0 V.
(4) Measured between I
(1)
= 15 V
(3)
, RT= 10 k Ω , CT= 3.3 nF, over recommended operating free-air temperature range (unless otherwise specified)
PARAMETER TEST CONDITIONS UNIT
(3) (4)
(3)
above the start threshold before setting it to 15 V.
CC
COMP = 5 V 0.9 1 1.1 0.9 1 1.1 V
V
= 12 V to 25 V 70 70 dB
CC
and COMP, with the input changing from 0 V to 0.8 V.
SENSE
TL284xB TL384xB
MIN TYP
(2)
MAX MIN TYP
(2)
2.85 3 3.15 2.85 3 3.15 V/V
MAX
6
Submit Documentation Feedback
www.ti.com
HIGH-PERFORMANCE CURRENT-MODE PWM CONTROLLERS
TL284xB , TL384xB
SLVS610B – AUGUST 2006 – REVISED JULY 2007
Output Section Electrical Characteristics
V
CC
High-level output voltage V
Low-level output voltage V
Rise time CL= 1 nF, TJ= 25 ° C 50 150 50 150 ns
Fall time CL= 1 nF, TJ= 25 ° C 50 150 50 150 ns
UVLO saturation V
(1) Adjust V
(2) All typical values are at TJ= 25 ° C.
(1)
= 15 V
, RT= 10 k Ω , CT= 3.3 nF, over recommended operating free-air temperature range (unless otherwise specified)
PARAMETER TEST CONDITIONS UNIT
TL284xB TL384xB
MIN TYP
(2)
MAX MIN TYP
(2)
IOH= –20 mA 13 13.5 13 13.5
IOH= –200 mA 12 13.5 12 13.5
IOL= 20 mA 0.1 0.4 0.1 0.4
IOL= 200 mA 1.5 2.2 1.5 2.2
= 5 V, IOL= 1 mA 0.7 1.2 0.7 1.2 V
CC
above the start threshold before setting it to 15 V.
CC
MAX
Undervoltage-Lockout Section Electrical Characteristics
V
CC
Start threshold voltage V
Minimum operating voltage
after start-up
(1) Adjust V
(2) All typical values are at TJ= 25 ° C.
(1)
= 15 V
, RT= 10 k Ω , CT= 3.3 nF, over recommended operating free-air temperature range (unless otherwise specified)
PARAMETER TEST CONDITIONS UNIT
TL284xB TL384xB
MIN TYP
(2)
MAX MIN TYP
(2)
TLx842B, TLx844B 15 16 17 14.5 16 17.5
TLx843B, TLx845B 7.8 8.4 9 7.8 8.4 9
TLx842B, TLx844B 9 10 11 8.5 10 11.5
TLx843B, TLx845B 7 7.6 8.2 7 7.6 8.2
above the start threshold before setting it to 15 V.
CC
MAX
V
Pulse-Width Modulator Section Electrical Characteristics
V
CC
Maximum duty cycle %
Minimum duty cycle 0 0 %
(1) Adjust V
(2) All typical values are at TJ= 25 ° C.
(1)
= 15 V
, RT= 10 k Ω , CT= 3.3 nF, over recommended operating free-air temperature range (unless otherwise specified)
PARAMETER TEST CONDITIONS UNIT
TL284xB TL384xB
MIN TYP
(2)
MAX MIN TYP
(2)
TL3842B, TL3843B 94 96 100 94 96 100
TL3844B, TL3845B 47 48 50 47 48 50
above the start threshold before setting it to 15 V.
CC
MAX
Supply Voltage Electrical Characteristics
V
CC
Start-up current 0.3 0.5 0.3 0.5 mA
Operating supply current VFB and I
Limiting voltage ICC= 25 mA 30 34 30 34 V
(1) Adjust V
(2) All typical values are at TJ= 25 ° C.
(1)
= 15 V
, RT= 10 k Ω , CT= 3.3 nF, over recommended operating free-air temperature range (unless otherwise specified)
PARAMETER TEST CONDITIONS UNIT
at 0 V 11 17 11 17 mA
SENSE
above the start threshold before setting it to 15 V.
CC
TL284xB TL384xB
MIN TYP
(2)
MAX MIN TYP
(2)
MAX
Submit Documentation Feedback
7
www.ti.com
-20
0
20
40
60
80
100
1 . E +0 1 1 . E +0 2 1 . E +0 3 1 . E +0 4 1 . E +0 5 1 . E +0 6 1 . E +0 7
f – Frequency – Hz
A
VOL
– Open-Loop Voltage Gain – dB
-100
-50
0
50
100
150
200
Phase Margin – deg
VCC= 15V
RL= 100 kX
TA= 25°C
Phase
Gain
kΩ
10 100
1k
10k 100k
1M 10M
0
5
10
15
20
25
0 5 10 15 20 25 30 35 40
V
CC
– Supply Voltage – V
I
CC
– Supply Current – mA
TL2845
TL2842
0
0.2
0.4
0.6
0.8
1
1.2
0 1 2 3 4 5 6 7 8
V
O
– Error Amplifier Output Voltage – V
V
th
– Current-Sense Input Threshold – V
VIN= 15 V
TA= 125°C
TA= 25°C
TA= -55°C
7.4
7.6
7.8
8
8.2
8.4
8.6
8.8
9
9.2
-55 -35 -15 5 25 45 65 85 105 125 145
T
A
– Temperature – °C
I
disharge
– Oscillator Discharge Current – mA
VIN= 15 V
V
OSC
= 2 V
TL284xB , TL384xB
HIGH-PERFORMANCE CURRENT-MODE PWM CONTROLLERS
SLVS610B – AUGUST 2006 – REVISED JULY 2007
TYPICAL CHARACTERISTICS
SUPPLY CURRENT GAIN AND PHASE
ERROR AMPLIFIER OPEN-LOOP
vs vs
SUPPLY VOLTAGE FREQUENCY
CURRENT-SENSE INPUT THRESHOLD OSCILLATOR DISCHARGE CURRENT
ERROR AMPLIFIER OUTPUT VOLTAGE TEMPERATURE
8
vs vs
Submit Documentation Feedback
www.ti.com
-60
-50
-40
-30
-20
-10
0
0 20 40 60 80 100 120 140 160
I
src
– Source Current – mA
Reference Voltage Delta – mV
TA= -40°C
TA= 25°C
TA= 125°C
4.8
4.85
4.9
4.95
5
5.05
5.1
5.15
5.2
-55 -30 -5 20 45 70 95 120 145
T
A
– Temperature – °C
V
ref
– Reference Voltage – V
40
60
80
100
120
140
160
180
-55 -30 -5 20 45 70 95 120 145
T
A
– Temperature – °C
I
SC
– Short-Circuit Current – mA
VIN= 15 V
0
1
2
3
4
5
6
7
8
9
10
0 100 200 300 400 500 600 700 800
I
O
– Output Load Current – mA
Sink Saturation Voltage – V
-10
-9
-8
-7
-6
-5
-4
-3
-2
-1
0
Source Saturation
Sink Saturation
TA= 25°C
TA= -55°C
TA= -55°C
TA= 25°C
HIGH-PERFORMANCE CURRENT-MODE PWM CONTROLLERS
TYPICAL CHARACTERISTICS (continued)
TL284xB , TL384xB
SLVS610B – AUGUST 2006 – REVISED JULY 2007
REFERENCE VOLTAGE REFERENCE VOLTAGE
vs vs
SOURCE CURRENT TEMPERATURE
REFERENCE SHORT-CIRCUIT CURRENT OUTPUT SATURATION VOLTAGE
vs vs
TEMPERATURE LOAD CURRENT
Submit Documentation Feedback
9
Loading...