4 layers96 × 60 mm
SOIC-8-EP
Overview
The TX4138 is a DC DC Converter made by XDS in a SOIC-8-EP package with 9 pins. -40℃~+85℃@(TA) 1 200kHz 4.5V~60V 400uA 4A 800mV~40V Adjustable Buck Buck Built-in No SOIC-8-EP DC-DC Converters ROHS.
PCBKit's library has its KiCad symbol (EasyEDA_Cloud:TX4138, from EasyEDA), ready for a KiCad board. 11,071 are in stock at JLCPCB (part C329267). 3 open-source boards in 3 repositories on GitHub use it.
Symbol
Footprint
The library has no footprint for this part yet.
From the datasheet
12- Supply, least
- 4.5 V · VIN, recommended operating min · p. 2
- Supply, most
- 60 V · VIN, recommended operating max · p. 2
- Supply, absolute maximum
- 62 V · VIN and VILIM, absolute max · p. 2
- Works from
- -40 °C · Operating temperature min · p. 2
- Works up to
- 85 °C · Operating temperature max · p. 2
- Junction, hottest
- 150 °C · Junction temperature absolute max · p. 2
- Takes working
- 400 µA · Quiescent current typical, VEN = 2V, VFB = 1V · p. 3
- Gives
- 4 A · Continuous output current max · p. 1
- Feedback reference
- 805 mV · Feedback voltage typical, 4.5V ≤ VIN ≤ 80V · p. 3
- Switches at
- 200 kHz · Oscillator frequency typical, VFB = 0.6V · p. 3
- Junction to air (ESOIC8)
- 45 K/W · Junction to ambient, approximately 42x45mm^2 of 1 oz copper · p. 2
- Junction to case (ESOIC8)
- 15 K/W · Junction to case, approximately 42x45mm^2 of 1 oz copper · p. 2
What it is and has
11- Input voltage range
- 4.5V to 60V · p. 1
- Output voltage
- Adjustable from 0.8V to 40V · p. 1
- Light-load operation
- Power Save Mode · p. 1
- Peak current
- Programmable maximum · p. 1
- Internal power switch
- 32mΩ MOSFET · p. 1
- Efficiency
- 93% at Vin=60V, Vout=12V, 2A · p. 1
- Efficiency
- 84.5% at Vin=60V, Vout=5V, 2A · p. 1
- Switching frequency
- Fixed 200KHz · p. 1
- Protection
- Thermal shutdown · p. 1
- Protection
- Cycle-by-cycle overcurrent protection · p. 1
- Package
- 8-Pin ESOIC8 · p. 1
Around it
13- cap 100uF
- between VIN and GND; C1A, 100V electrolytic input capacitor; place close to VIN and GND. · p. 5
- cap 0.1uF
- between VIN and GND; C1B, 100V ceramic input capacitor, 0603. · p. 5
- cap 470uF
- between VOUT and GND; C2, 16V electrolytic output capacitor. · p. 5
- cap 100nF
- between BS and R3; C3, 100V X7R ceramic bootstrap capacitor; series path with R3 between BS and SW. · p. 5
- res 5.1Ω
- between C3 and SW; R3, 1% bootstrap resistor, 0603; series path with C3 between BS and SW. · p. 5
- cap 12pF
- between VOUT and FB; C4, 50V X7R ceramic loop compensation capacitor, 0603. · p. 5
- diode SS510
- between GND and SW; D1, 100V, 5A Schottky diode in SMC; use low forward voltage for efficiency. · p. 5
- ind 33uH
- between SW and VOUT; L1, CDRH127, 3A, 58mΩ. · p. 5
- res 300KΩ
- between VOUT and FB; R1, 1% feedback divider resistor, 0603; 5V example. · p. 5
- res 57.1KΩ
- between FB and GND; R2, 1% feedback divider resistor, 0603; 5V example. · p. 5
- res 30mΩ
- between VIN and ILIM; R4, 1% current sense resistor, 1206; 5V/2A BOM. · p. 5
- res 20
- between VIN and ILIM; Rsense in mΩ for maximum output current of 3A, from Table 2. · p. 4
- res 15
- between VIN and ILIM; Rsense in mΩ for maximum output current of 4A, from Table 2. · p. 4
Specifications
23| Parameter | Conditions | As printed | Page |
|---|---|---|---|
| Supply Voltage VIN ,VILIM | max 62 V | 2 | |
| VSW VSW | Upper limit VIN + 0.3V | min -0.3 V | 2 |
| VPOK VPOK | min 0 · max 45 V | 2 | |
| All Other Pins | min -0.3 · max 6.5 V | 2 | |
| Junction Temperature | max 150 °C | 2 | |
| Lead Temperature | max 260 °C | 2 | |
| Storage Temperature | min -65 · max 150 °C | 2 | |
| Supply Voltage VIN | min 4.5 · max 60 V | 2 | |
| O Voltage VOUT | min 0.8 · max 40 V | 2 | |
| Operating Temperature | min -40 · max 85 °C | 2 | |
| θJA θJA | ESOIC8; measured on approximately 42x45mm^2 of 1 oz copper | typ 45 °C/W | 2 |
| θJC θJC | ESOIC8; measured on approximately 42x45mm^2 of 1 oz copper | typ 15 °C/W | 2 |
| Feedback Voltage VFB | VIN = 12V, TA = +25°C unless otherwise noted; 4.5V ≤ VIN ≤ 80V | min 0.785 · typ 0.805 · max 0.825 V | 3 |
| Feedback Bias Current IBIAS(FB) | VIN = 12V, TA = +25°C; VFB = 0.8V | typ 10 nA | 3 |
| Switch On Resistance RDS(ON) | VIN = 12V, TA = +25°C | typ 32 mΩ | 3 |
| Oscillator Frequency fSW | VIN = 12V, TA = +25°C; VFB = 0.6V | min 160 · typ 200 · max 240 KHz | 3 |
| Fold-Back Frequency | VIN = 12V, TA = +25°C; VFB = 0V | typ 70 KHz | 3 |
| Boot-Strap Voltage VBST - VSW | VIN = 12V, TA = +25°C | typ 6 V | 3 |
| Minimum On Time (5) tON | VIN = 12V, TA = +25°C; VFB = 1V; guaranteed by design | typ 100 ns | 3 |
| Under Voltage Lockout Threshold Rising | VIN = 12V, TA = +25°C | min 3 · typ 3.3 · max 3.6 V | 3 |
| Under Voltage Lockout Threshold Hysteresis | VIN = 12V, TA = +25°C | min 200 mV | 3 |
| Supply Current (Quiescent) | VIN = 12V, TA = +25°C; VEN = 2V, VFB = 1V | typ 400 · max 700 uA | 3 |
| Thermal Shutdown (5) | VIN = 12V, TA = +25°C; guaranteed by design | typ 160 °C | 3 |
Pins, by the datasheet
9- 1 SW
- Switch output; connect to the switching end of the inductor. · p. 2
- 2 ILIM
- Programs maximum peak current through an accurate sense resistor between ILIM and VIN. · p. 2
- 3 VIN
- Supply input, +4.5V to +60V; place CIN as close to the IC as possible to prevent input voltage spikes. · p. 2
- 4 Gnd
- Output voltage reference ground; place outside the D1 to CIN ground path to prevent switching noise. · p. 2
- 5 FB
- Feedback input from an external output-to-ground resistor divider; frequency foldback operates below 250mV. · p. 2
- 6 EN
- Drive low to turn off the chip; floating enables it. · p. 2
- 7 POK
- Power good output, low when FB is below 90% of 0.8V; use an external pull-up, or ground or float when unused. · p. 2
- 8 BS
- Positive rail for the high-side gate driver; connect a 100nF ceramic capacitor and 10ohm resistor between BS and SW. · p. 2
- 9 ILIM
- Programs maximum peak current through an accurate sense resistor between ILIM and VIN. · p. 2
Ordering codes, by the datasheet
1- TX4138
- ESOIC8 · Temperature range -40°C to 85°C · p. 2
Parameters
18- Features
- Cycle-by-cycle current limiting
- Frequency - Switching
- 200kHz
- Function
- Step-down type
- Junction Temperature(Max)
- 150℃
- Number of Outputs
- 1
- Operating Temperature
- -40℃~+85℃
- Output Current
- 4A
- Output Type
- Adjustable
- Output Voltage
- 800mV~40V
- Quiescent Current
- 400uA
- Reference Voltage
- 805mV
- Switch tube (built-in/external)
- Built-in
- Synchronous Rectifier
- No
- Thermal Resistance(Junction to Ambient)
- 45℃/W
- Thermal Resistance(Junction to Case)
- 15℃/W
- Topology
- Buck
- Voltage - Supply
- 4.5V~60V
- Voltage - Supply(Absolute Max)
- 62V
Order codes
1- TX4138LCSC C329267
Pinout
9| Pin | Name | Type |
|---|---|---|
| 1 | SW | Unspecified |
| 2 | ILIM | Unspecified |
| 3 | VIN | Unspecified |
| 4 | GND | Unspecified |
| 5 | FB | Unspecified |
| 6 | EN | Unspecified |
| 7 | POK | Unspecified |
| 8 | BS | Unspecified |
| 9 | ILIM | Unspecified |
Open-source boards using it
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Questions
Is there a KiCad symbol and footprint for the TX4138?
Yes. The symbol is EasyEDA_Cloud:TX4138, both drawn on this page. PCBKit places them on a board for you when you design with it.
What package is the TX4138?
SOIC-8-EP, with 9 pins.
Where is the TX4138 datasheet?
XDS publishes it: the Datasheet link on this page opens it.
Where can I order the TX4138?
JLCPCB lists it as part C329267, with 11,071 in stock; the sellers' links on this page open their listings.
Which open-source boards use the TX4138?
3 boards in 3 repositories on GitHub; the most starred are listed on this page, with their KiCad files.