LTC4057ES5-4.2#TRPBF - 600mA Linear Li-Ion Charger, TSOT-23-5
Référence : LTC4057ES5-4.2#TRPBF ✓ Actif| Qté | Prix unitaire | Total |
|---|---|---|
| 1 | $2.85 | $2,85 |
| 10 | $2.58 | $25,80 |
| 100 | $2.13 | $213,00 |
| 500 | $1.85 | $925,00 |
| 1 000 | $1.55 | $1 550,00 |
| 2 500 | $1.32 | $3 300,00 |
LTC4057ES5-4.2#TRPBF Présentation
What is a linear Li-Ion battery charger? A linear Li-Ion charger IC regulates current and voltage from a DC source (typically USB or a wall adapter) into a single-cell Li-Ion/Li-Polymer battery using a low-dropout linear topology. Within the broader power-management hierarchy, linear chargers sit beneath switching chargers as a simpler, lower-noise, smaller-PCB solution. They trade efficiency for simplicity: heat is dissipated across an internal pass element rather than being switched at high frequency.
Key features of the LTC4057ES5-4.2 include a fixed 4.2V output (the "-4.2" suffix), a programmable charge current up to 600 mA set by a single external resistor on PROG, an internal thermal-regulation loop that automatically reduces charge current at high die temperatures, an open-drain CHRG status indicator, and a low quiescent current. The device operates from a wide input range suitable for USB and adapter sources, requires no external MOSFET, sense resistor, or blocking diode, and offers a precision C/10 charge-termination method.
Architecturally, the LTC4057ES5-4.2 uses a P-channel pass transistor that allows the input to be brought to ground when charging is complete, eliminating the need for a blocking diode. The thermal-regulation loop monitors die temperature and folds back charge current when the junction exceeds approximately 105 C, allowing continuous operation at high ambient temperatures without an external heatsink.
Typical applications include standalone single-cell Li-Ion chargers, USB-powered charging pods, Bluetooth headsets, wearables, IoT sensor nodes, and backup battery packs. Its small TSOT-23-5 footprint makes it ideal for space-constrained designs where a switching charger is overkill.
When designing with this part, place the input bypass capacitor (4.7 uF minimum) close to IN and the battery capacitor close to BAT. Set charge current with RPROG = 1200 / IBAT (k-ohm, mA). Do not exceed 600 mA charge current. Verify thermal dissipation: at 5 V IN, 4.2 V BAT, and 500 mA, dissipation is roughly 0.4 W.
This page synthesizes distributor pricing, pin-for-pin drop-in alternatives from the LTC4057 family and competing TSOT-23-5 chargers, and practical thermal design guidance not bundled in the manufacturer datasheet PDF.
Alternatives de remplacement direct pour LTC4057ES5-4.2#TRPBF — même boîtier, compatible broche à broche. Les références à boîtier différent nécessitant une retouche du PCB sont exclues.
Outil de comparaison rapide — sélectionnez des références alternatives pour une comparaison côte à côte :
LTC4057ES5-4.2#TRMPBF
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
LTC4057ES5-4.1#TRPBF
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
LTC4054XES5-4.2#TRPBF
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
LTC4054ES5-4.2#TRPBF
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
MCP73831T-2ACI/OT
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
LTC4057ES5-4.2#TRPBF Spécifications
| Fonction | Linear Li-Ion battery charger |
| Battery Chemistry | Lithium-Ion / Lithium-Polymer (single cell) |
| Float Voltage (Charge Termination) | 4.2 V (fixed) |
| Maximum Charge Current | 600 mA (programmable via PROG pin) |
| Charge Topology | Linear, constant-current / constant-voltage (CC/CV) |
| Pass Element | Internal P-channel MOSFET |
| Thermal Regulation | Yes, automatic current foldback at high die temperature |
| Status Output | Open-drain CHRG pin |
| Plage de température de fonctionnement | -40 C to +85 C (commercial/extended) |
| Boîtier | TSOT-23-5 (S5) ThinSOT |
| Type de montage | Surface Mount |
| Niveau MSL | 1 |
| Statut RoHS | Compliant |
| Lead-Free / Pbfree | Yes (#PBF suffix) |
| External Components Required | PROG resistor, IN cap, BAT cap (no MOSFET, sense resistor, or blocking diode) |
Configuration des broches de LTC4057ES5-4.2#TRPBF
| Broche 1 | IN — Input supply voltage; bypass with 4.7 uF minimum ceramic capacitor |
| Broche 2 | GND — Ground reference |
| Broche 3 | BAT — Battery connection; charge current flows out of this pin to the cell |
| Broche 4 | PROG — Charge current program pin; connect resistor to GND to set IBAT (1200 / RPROG) |
| Broche 5 | CHRG — Open-drain charge status output; pulls low while charging |
Applications typiques
LTC4057ES5-4.2#TRPBF convient pour 7 applications: Standalone Single-Cell Li-Ion USB Charger, Bluetooth Headset / Earbud Charging Case, Wearable / Fitness Tracker Battery Charging, IoT Sensor Node Li-Ion Backup Charging, Portable Medical Device Single-Cell Charger, Toy / Consumer Electronics Single-Cell Charger, USB-C Powered Li-Ion Charging Pod.
Standalone Single-Cell Li-Ion USB Charger
The LTC4057ES5-4.2 fits standalone single-cell Li-Ion USB chargers because its 600 mA programmable current, 4.2 V fixed float, and integrated thermal regulation match the typical 5 V USB input and a single 3.7 V Li-Ion/Li-Polymer cell. With a 4.7 uF input cap and a 2 k-ohm PROG resistor, designers get a full CC/CV charger in a 5-pin TSOT-23-5 footprint. Compared with a switching charger, this linear solution has no inductor, lower EMI, and a smaller PCB area at the cost of ~0.4 W dissipation at 5 V/500 mA.
Recommandé
Bluetooth Headset / Earbud Charging Case
The 5-pin TSOT-23-5 footprint and 600 mA charge current make the LTC4057ES5-4.2 ideal for Bluetooth earbud charging cases that recharge small Li-Ion/Li-Polymer cells at 100-300 mA. The internal thermal-regulation loop protects the small enclosure from overheating during continuous top-off charging, and the open-drain CHRG pin drives an LED to indicate charging status without extra glue logic. Pin-compatible ADI family members such as the LTC4054ES5-4.2 can be substituted at lower cost when thermal-loop behavior is not required.
Recommandé
Wearable / Fitness Tracker Battery Charging
Wearables and fitness trackers need a single-cell Li-Polymer charger that fits a tiny PCB next to the battery. The LTC4057ES5-4.2's TSOT-23-5 footprint (approx. 2.9 mm x 1.6 mm) and 600 mA maximum current are well matched to the 100-300 mA typical charge rate of a 50-200 mAh wearable cell. The internal thermal loop prevents skin-adjacent overheating in wristbands, and the wide input range accepts USB or wireless-charging receiver outputs. Use a 12 k-ohm PROG resistor for 100 mA charge into small cells.
Recommandé
IoT Sensor Node Li-Ion Backup Charging
Battery-backed IoT sensor nodes (Zigbee, LoRa, Matter) commonly recharge a small Li-Ion cell from USB or a 5 V harvest source. The LTC4057ES5-4.2's low external-component count - just two caps and one PROG resistor - minimizes BOM cost and PCB area on a coin-cell-sized sensor module. The CHRG open-drain output can be wired to a GPIO so the host MCU knows when to enter low-power sleep. Thermal regulation prevents overheating when the device is sealed in an IP-rated enclosure with limited airflow.
Recommandé
Portable Medical Device Single-Cell Charger
Handheld medical devices such as pulse oximeters, glucose meters, and portable nebulizers often use a single Li-Ion/Li-Polymer cell recharged from USB. The LTC4057ES5-4.2's +/- 1 percent float-voltage accuracy preserves cell cycle life and the integrated thermal-regulation loop provides an additional safety margin during continuous top-off. The TSOT-23-5 footprint and Pb-free construction suit compact, disposable-cartridge form factors. Pair with an LTC4065-style fuel gauge if state-of-charge telemetry is needed.
Recommandé
Toy / Consumer Electronics Single-Cell Charger
Cost-sensitive consumer toys, remote controls, and small appliances that use a single Li-Ion cell benefit from the LTC4057ES5-4.2's minimal BOM and TSOT-23-5 footprint. Designers set charge current with one resistor, place two bypass caps, and have a complete CC/CV charger with status indication. The internal P-channel architecture eliminates the need for a blocking diode, which is a common failure point in low-cost chargers. Tape-and-reel packaging supports high-volume SMT assembly.
Recommandé
USB-C Powered Li-Ion Charging Pod
USB-C charging pods for flashlights, cameras, and vape devices often step down from a 5 V USB-C input to a single Li-Ion cell. The LTC4057ES5-4.2 provides direct 5 V to 4.2 V linear regulation with up to 600 mA of charge current, which is appropriate for 500-1000 mAh cells. The internal thermal-regulation loop prevents overheating when the pod is sealed or operated at high ambient temperature. Status indication via the CHRG pin can drive an LED or feed a USB-C PD controller for legacy-mode charging.
Recommandé
Récapitulatif des produits recommandés
Données de référence d'ingénierie pour LTC4057ES5-4.2#TRPBF — comparaison, recommandations de conception et informations de conformité.
Guide de sélection
Comparaison avec les alternatives
| Paramètre | Ce produit | LTC4057ES5-4.2#TRMPBF | LTC4057ES5-4.1#TRPBF | LTC4054XES5-4.2#TRPBF | LTC4054ES5-4.2#TRPBF | MCP73831T-2ACI/OT |
|---|---|---|---|---|---|---|
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Microchip Technology |
| Package | TSOT-23-5 | TSOT-23-5 - same | TSOT-23-5 - same | TSOT-23-5 - same | TSOT-23-5 - same | TSOT-23-5 - same |
| Float Voltage | 4.2 V (fixed) | 4.2 V (fixed) | 4.1 V (fixed) | 4.2 V (fixed) | 4.2 V (fixed) | 4.2 V (fixed) |
| Max Charge Current | 600 mA | 600 mA | 600 mA | 800 mA | 500 mA | 500 mA |
| Thermal Regulation | Yes (built-in) | Yes | Yes | No | No | No |
| External MOSFET Required | No (internal P-channel) | No | No | No | No | No |
| Status Indicator | Open-drain CHRG | Open-drain CHRG | Open-drain CHRG | Open-drain CHRG | Open-drain CHRG | Open-drain STAT |
| Approx. Unit Price (1000+ qty) | $1.55 | ~$1.55 (same die) | ~$1.55 | ~$1.45 | ~$1.20 | ~$0.55 |
Principaux différenciateurs
- Built-in thermal regulation current foldback (vs LTC4054ES5-4.2)
- Integrated P-channel MOSFET - no blocking diode (vs Discrete linear charger designs)
- 600 mA charge current in TSOT-23-5 (vs MCP73831T-2ACI/OT)
- Wide ADI charger family pin compatibility (vs Other vendors' Li-Ion chargers)
Notes de conception
At 5 V USB input, 4.2 V float, and 500 mA charge current, the LTC4057ES5-4.2 dissipates approximately (5.0 - 3.7) x 0.5 = 0.65 W into the TSOT-23-5 package. The internal thermal-regulation loop engages when the die reaches ~105 C and reduces charge current to maintain that limit. Estimated: theta_JA for TSOT-23-5 on a 1 sq-in copper pour is approximately 100 C/W; with 0.65 W the junction rises ~65 C above ambient, leaving ~40 C margin to the 125 C absolute maximum. Use larger copper pours or reduced charge current (raise RPROG) if the device is sealed inside an enclosure with no airflow.
Place the input bypass capacitor (4.7 uF X5R minimum, X7R preferred) within 2 mm of the IN pin, and the battery capacitor (4.7 uF) within 2 mm of the BAT pin. Keep the PROG trace short and direct to avoid noise pickup on the current-sense node. The exposed TSOT-23-5 die-attach paddle (if present, on the bottom) should be soldered to a copper pour connected to GND to maximize heat dissipation. Per the Analog Devices datasheet, the thermal pad is internally connected to GND; not soldering it can reduce charge current by 20-30 percent due to higher junction temperature at the same power level.
Do not exceed 600 mA charge current - the internal MOSFET and sense resistor are sized for this maximum and exceeding it can cause permanent damage. Do not omit the PROG resistor; leaving PROG floating causes the charger to default to maximum current and may exceed the cell's rated C-rate. Ensure the input supply can source the full programmed charge current plus IC quiescent draw - weak USB sources (100 mA default) will collapse under 600 mA load. The CHRG pin is open-drain and requires a pull-up resistor (typically 100 k-ohm to VCC); do not connect it directly to a voltage source. Finally, verify that the battery does not exceed the absolute maximum BAT pin voltage if hot-plugged during charging.
The LTC4057ES5-4.2 accepts input from any 5 V +/- 5 percent source, including USB ports, wall adapters, and the output of a downstream switching regulator. The internal P-channel architecture eliminates the need for a blocking diode between IN and BAT, simplifying the BOM and reducing forward-voltage loss. When the input is removed, the LTC4057ES5-4.2 enters a low-quiescent sleep mode that minimizes battery drain - the datasheet specifies this as a key feature versus competing chargers that leak several microamps back through the input pin.
Informations de conformité
Pb-free (#PBF suffix) and RoHS compliant per Analog Devices product page. The LTC4057 family is not AEC-Q100 qualified - not intended for automotive under-hood applications. Halogen-free status not explicitly stated in provided data.
