TLV431X
Adjustable Precision Shunt RegulatorThe TLV431X is a adjustable precision shunt regulator from Texas Instruments. View the full TLV431X datasheet below including key specifications, electrical characteristics, absolute maximum ratings.
Manufacturer
Texas Instruments
Category
Adjustable Precision Shunt Regulator
Key Specifications
| Parameter | Value |
|---|---|
| Case/Package | SOT-23 |
| Cathode Current | 80 µA |
| Current - Cathode | 80 µA |
| Current - Cathode | 80 µA |
| Output Current | 15 mA |
| Height | 1.22 mm |
| Lead Free | Lead Free |
| Length | 2.92 mm |
| Lifecycle Status | Production (Last Updated: 2 days ago) |
| Manufacturer Lifecycle Status | ACTIVE (Last Updated: 2 days ago) |
| Max Input Voltage | 7 V |
| Max Operating Temperature | 125 °C |
| Max Output Current | 15 mA |
| Max Output Voltage | 6 V |
| Min Input Voltage | 1.24 V |
| Min Operating Temperature | -40 °C |
| Min Output Voltage | 1.24 V |
| Mount | Surface Mount |
| Mounting Type | Surface Mount |
| Number of Pins | 3 |
| Operating Temperature | 0°C ~ 70°C (TA) |
| Output Current | 15 mA |
| Output Type | Adjustable |
| Output Type | Adjustable |
| Output Voltage | 6 V |
| Package / Case | TO-236-3, SC-59, SOT-23-3 |
| Packaging | MouseReel |
| Packaging | Cut Tape |
| Radiation Hardening | No |
| REACH SVHC | No |
| Reference Type | Adjustable, Shunt |
| Reference Type | Shunt |
| Reference Voltage | 6 V |
| RoHS | Compliant |
| Schedule B | 8542390000 |
| Standard Pack Qty | 3000 |
| Supplier Device Package | SOT-23-3 |
| Supplier Device Package | SOT-23-3 |
| Temperature Coefficient | 39 ppm/°C |
| Thickness | 1 mm |
| Tolerance | ±1% |
| Tolerance | 1 % |
| Output Voltage (Max) | 6 V |
| Output Voltage | 1.24V |
| Width | 1.3 mm |
Overview
Part: TLV431, TLV431A, TLV431B — Texas Instruments
Type: Low-Voltage Adjustable Precision Shunt Regulator
Description: Low-voltage 3-terminal adjustable voltage reference with a 1.24 V reference, adjustable output from VREF to 6 V, and 80 μA typical operational cathode current.
Operating Conditions:
- Supply voltage: VREF–6 V
- Operating temperature: 0 to 70 °C (suffix-dependent — see Electrical Characteristics tables for grade-specific ranges)
- Cathode current: 0.1 mA to 15 mA
Absolute Maximum Ratings:
- Max supply voltage: 7 V (Cathode voltage)
- Max continuous current: 20 mA (Continuous cathode current)
- Max junction/storage temperature: 150 °C (Operating virtual junction temperature)
Key Specs:
- Reference voltage (VREF): 1.24 V (typ)
- Reference voltage tolerance: -1% (for TLV431A at 25°C)
- Typical temperature drift: -4 mV (0°C to 70°C)
- Minimum cathode current for regulation: 55 μA (typ)
- Dynamic impedance (zKA): 0.25 Ω (typ)
- Reference terminal current (Iref): 0.15 μA (typ)
- Off-state cathode current (IK(off)): 0.001 μA (typ)
Features:
- Low-Voltage Operation, VREF = 1.24 V
- Adjustable Output Voltage, VO = VREF to 6 V
- Reference Voltage Tolerances at 25°C
- Low Operational Cathode Current, 80 μA Typ
- 0.25Ω Typical Output Impedance
- Ultra-Small SC-70 Package Offers 40% Smaller Footprint Than SOT-23-3
Applications:
- Adjustable Voltage and Current Referencing
- Secondary Side Regulation in Flyback SMPSs
- Zener Replacement
- Voltage Monitoring
- Comparator with Integrated Reference
Package:
- SOT-23 (3)
- SOT-23 (5)
- SC70 (6)
- TO-92 (3)
- SOIC (8)
Features
- 1 · Low-Voltage Operation, VREF = 1.24 V
- Adjustable Output Voltage, VO = VREF to 6 V
- Reference Voltage Tolerances at 25°C
- -0.5% for TLV431B
- -1% for TLV431A
- -1.5% for TLV431
- Typical Temperature Drift
- -4 mV (0°C to 70°C)
- -6 mV (-40°C to 85°C)
- -11 mV (-40°C to 125°C)
- Low Operational Cathode Current, 80 μA Typ
- 0.25Ω Typical Output Impedance
- Ultra-Small SC-70 Package Offers 40% Smaller Footprint Than SOT-23-3
- See TLVH431 and TLVH432 for:
- -Wider VKA (1.24 V to 18 V) and IK (80 mA)
- -Additional SOT-89 Package
- -Multiple Pinouts for SOT-23-3 and SOT-89 Packages
- On Products Compliant to MIL-PRF-38535, All Parameters Are Tested Unless Otherwise Noted. On All Other Products, Production Processing Does Not Necessarily Include Testing of All Parameters.
TLV431, TLV431A, TLV431B
SLVS139V -JULY 1996-REVISED JANUARY 2015
Applications
- Adjustable Voltage and Current Referencing
- Secondary Side Regulation in Flyback SMPSs
- Zener Replacement
- Voltage Monitoring
- Comparator with Integrated Reference
Pin Configuration
Electrical Characteristics
at 25°C free-air temperature (unless otherwise noted)
| PARAMETER | PARAMETER | TLV431 | TLV431 | TLV431 | UNIT | |||
|---|---|---|---|---|---|---|---|---|
| MIN | TYP | MAX | ||||||
| REF | 1.222 | 1.24 | 1.258 | V | ||||
| V | TLV431C | 1.21 | 1.27 | V | ||||
| Reference voltage | V | TLV431I | 1.202 | 1.278 | V | |||
| V | TLV431Q | 1.194 | 1.286 | V | ||||
| V REF(dev) | TLV431C | 4 | 12 | mV | ||||
| V REF deviation over full temperature range (2) | TLV431I TLV431Q | 6 11 | 20 31 | mV mV | ||||
| REF KA V V /c68 /c68 | Ratio of V REF change in cathode voltage change | V KA = V REF to 6 V, I K = 10 mA (see Figure 20) | V KA = V REF to 6 V, I K = 10 mA (see Figure 20) | V KA = V REF to 6 V, I K = 10 mA (see Figure 20) | -1.5 | -2.7 | mV/V | |
| I ref | Reference terminal current | I K = 10 mA, R1 = 10 k Ω , R2 = open (see Figure 20) | I K = 10 mA, R1 = 10 k Ω , R2 = open (see Figure 20) | I K = 10 mA, R1 = 10 k Ω , R2 = open (see Figure 20) | 0.15 | 0.5 | μA | |
| I ref(dev) | I ref deviation over full temperature (2) | TLV431C | 0.05 | 0.3 | μA | |||
| range | TLV431I TLV431Q | 0.1 0.15 | 0.4 0.5 | μA μA | ||||
| I | Minimum cathode current for | TLV431C/I | 55 | 80 | ||||
| K(min) | regulation | TLV431Q | 55 | 100 | ||||
| I K(off) | Off-state cathode current | 0.001 | 0.1 | μA | ||||
| \ | z KA \ | Dynamic impedance (3) | V KA = V REF , f ≤ 1 kHz, I K = 0.1 mA to 15 mA (see Figure 19) | V KA = V REF , f ≤ 1 kHz, I K = 0.1 mA to 15 mA (see Figure 19) | V KA = V REF , f ≤ 1 kHz, I K = 0.1 mA to 15 mA (see Figure 19) | 0.25 |
(2) The deviation parameters VREF(dev) and I ref(dev) are defined as the differences between the maximum and minimum values obtained over the rated temperature range. The average full-range temperature coefficient of the reference input voltage, α VREF, is defined as:
where Δ TA is the rated operating free-air temperature range of the device.
α VREF can be positive or negative, depending on whether minimum VREF or maximum VREF, respectively, occurs at the lower temperature.
- KA K ka V z I /c68 /c68 /c61 (3) The dynamic impedance is defined as spacer
When the device is operating with two external resistors (see Figure 20), the total dynamic impedance of the circuit is defined as:
Absolute Maximum Ratings
over operating free-air temperature range (unless otherwise noted) (1)
| MIN | MAX | UNIT | ||
|---|---|---|---|---|
| V KA | Cathode voltage (2) | 7 | V | |
| I K | Continuous cathode current range | -20 | 20 | mA |
| I ref | Reference current range | -0.05 | 3 | mA |
| Operating virtual junction temperature | 150 | °C | ||
| T stg | Storage temperature range | -65 | 150 | °C |
Recommended Operating Conditions
over operating free-air temperature range (unless otherwise noted)
| MIN | MAX | UNIT | ||
|---|---|---|---|---|
| V KA | Cathode voltage | V REF | 6 | V |
| I K | Cathode current | 0.1 | 15 | mA |
| T A | 0 | 70 | °C | |
| Operating free-air temperature range | -40 | 85 | °C | |
| -40 | 125 | °C |
Thermal Information
| TLV431x | TLV431x | TLV431x | TLV431x | TLV431x | TLV431x | ||
|---|---|---|---|---|---|---|---|
| THERMAL METRIC (1) | DCK | D | PK | DBV | DBZ | LP | |
| 6 PINS | 8 PINS | 3 PINS | 5 PINS | 3 PINS | 3 PINS | ||
| R θ JA | Junction-to-ambient thermal resistance | 87 | 97 | 52 | 206 | 206 | 140 |
| R θ JC(top) | Junction-to-case (top) thermal resistance | 259 | 39 | 9 | 131 | 76 | 55 |
Typical Application
Figure 22 shows the TLV431, TLV431A, or TLV431B used in a 3.3-V isolated flyback supply. Output voltage VO can be as low as reference voltage VREF (1.24 V ± 1%). The output of the regulator, plus the forward voltage drop of the optocoupler LED (1.24 + 1.4 = 2.64 V), determine the minimum voltage that can be regulated in an isolated supply configuration. Regulated voltage as low as 2.7 Vdc is possible in the topology shown in Figure 22.
The 431 family of devices are prevalent in these applications, being designers go to choice for secondary side regulation. Due to this prevalence, this section will further go on to explain operation and design in both states of TLV431 that this application will see, open loop (Comparator + Vref) & closed loop (Shunt Regulator).
Further information about system stability and using a TLV431 device for compensation can be found in the application note Compensation Design With TL431 for UCC28600, SLUA671.
Figure 22. Flyback With Isolation Using TLV431, TLV431A, or TLV431B as Voltage Reference and Error Amplifier
Related Variants
The following components are covered by the same datasheet.
| Part Number | Manufacturer | Package |
|---|---|---|
| TLV431ACDBZR | Texas Instruments | TO-236-3, SC-59, SOT-23-3 |
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