TC7660SCOA - 20mA Super Charge Pump Inverter | Microchip 8-SOIC
MPN: TC7660SCOA ✓ NakahandaTC7660SCOA Ulas
A charge pump (also called a switched-capacitor voltage inverter) is a type of DC-DC converter that uses capacitors rather than inductors to store and transfer energy. Charge pumps belong to the switched-capacitor converter family within the broader power management IC hierarchy. Unlike inductive buck/boost converters, charge pumps are EMI-quiet and use only two external capacitors, making them ideal for low-current negative rail generation where simplicity and noise performance outweigh efficiency.
Key features include 99.9% voltage conversion efficiency (typ), 20 mA output current capability, wide input voltage range up to +12V (vs 10V for original TC7660), and on-board oscillator at nominal 10 kHz frequency. The TC7660SCOA also supports a BOOST pin for higher switching frequencies when needed. The 8-SOIC package operates over -40°C to +85°C industrial temperature range with surface-mount assembly.
The architecture uses a CMOS switched-capacitor voltage inverter with integrated MOSFET switches clocked by an internal RC oscillator. The doubler/inverter topology transfers charge from input to reservoir capacitor on one clock phase and inverts on the other, producing a negative output without inductors or transformers. The result is a compact, low-noise negative supply solution with predictable EMI signature.
Typical applications include op-amp negative supply rails, LCD bias generators, data acquisition systems, EIA-232/EIA-422 level translators, and portable instrument negative rails. The 20 mA output comfortably drives a single op-amp negative rail or a small RS-232 transceiver charge pump supplement.
When designing with this device, ensure external reservoir and pump capacitors are low-ESR types rated for the switching frequency, and observe the LV pin voltage derating requirements above +10V input to maintain reliability.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
Mga alternatibo na pwedeng ilagay na TC7660SCOA — parehas na package, pin-to-pin na katugmang. Hindi kasama ang mga bahagi ng iba't-ibang package na nangangailangan ng pagpapaayos ng PCB.
Variante sa Seri na ito
Katulad na modelo sa serye na katugma sa pagpasok TC7660SCOA (parehas na form factor at footprint) — pagkakaiba sa Internal Oscillator Frequency, Mounting Type, Operating Temperature Range, Output Current, Package.
TC7660COA
✅ Drop-In📋 Alternatibo na Reference (hindi sa katalogo)
TC7660SEOA
✅ Drop-InMagkontak para sa presyo
Tingnan ang Datasheet →TC7660SCOA713
✅ Drop-In📋 Alternatibo na Reference (hindi sa katalogo)
ICL7660ESA
✅ Drop-In📋 Alternatibo na Reference (hindi sa katalogo)
ICL7660CBA
✅ Drop-In📋 Alternatibo na Reference (hindi sa katalogo)
TC7660SCOA Mga Pinakamataas na Rating at Electrical Characteristics
| Fungsi | Inverting / Step-Up Charge Pump |
| Topolohiya | Switched-Capacitor Voltage Inverter (Doubled) |
| Hanay ng Voltage ng Input | +1.5 V to +12 V |
| Hanay ng Output Volte | -1.5 V to -12 V (inverting); 3 V to 24 V (doubling mode) |
| Output Current | 20 mA |
| Voltage Conversion Efficiency | 99.9 % typ |
| Power Efficiency | 98 % typ |
| Kuru-kuryente ng Kapayapaan | 80 µA typ @ VIN = 5 V |
| Internal Oscillator Frequency | 10 kHz nominal |
| Packhaging | 8-SOIC (0.154 inch / 3.90 mm width) |
| Uri ng Pagpapasok | Surface Mount (SMD/SMT) |
| Hanay ng Temperature na Operasyon | -40 °C to +85 °C |
| Bilang ng Pin | 8 |
| External Components Required | 2 capacitors (no inductors) |
| Tindminan RoHS | Compliant |
| Pin-Compatible With | Industry standard TC7660, ICL7660 |
| LV Pin | Required for VIN > +10 V |
| BOOST Pin | Yes - increases oscillator frequency when connected |
Pin Configuration ng TC7660SCOA
| Pin 1 | CAP+ — Charge pump capacitor positive terminal |
| Pin 2 | CAP- — Charge pump capacitor negative terminal |
| Pin 3 | VOUT — Regulated negative output voltage (or V+ in doubler mode) |
| Pin 4 | LV — Low-voltage pin; ground for VIN < +5V, open for +5V to +12V |
| Pin 5 | GND — Ground reference |
| Pin 6 | OSC — Oscillator control; decouple with 100pF to reduce frequency |
| Pin 7 | V+ — Positive supply input (+1.5V to +12V) |
| Pin 8 | BOOST — Logic high to double oscillator frequency; connect to V+ or leave open |
Tipikal na mga Gamit
TC7660SCOA ay nararapat para sa 6 aplikasyons: Op-Amp Negative Supply Rail, EIA-232 / EIA-422 Level Translator Bias, LCD Bias Generator, Portable Instrument Power, Data Acquisition System Reference, Voltage Doubler (Doubled Mode).
Op-Amp Negative Supply Rail
The TC7660SCOA generates a clean -5 V or -12 V rail from a single +5 V or +12 V supply for dual-supply operational amplifiers, eliminating the cost and EMI of inductive buck-boost converters. Its 20 mA output comfortably powers one or two precision op-amps drawing 1-5 mA quiescent each, with 99.9% voltage conversion efficiency at typical loads. Compared to discrete resistor-divider biasing, the charge pump maintains regulation under dynamic load conditions and produces negligible output ripple above the oscillator fundamental.
Inirekomenda
EIA-232 / EIA-422 Level Translator Bias
The TC7660SCOA provides the negative bias required for RS-232 transceiver charge-pump supplementation and for EIA-422 line driver negative rails in isolated points and legacy communications. Its 8-SOIC footprint integrates beside common RS-232 transceivers, and 20 mA output is sufficient for a single driver channel. The device's lack of EMI makes it preferable to inductive converters in noise-sensitive interface circuits where conducted emissions must be minimized.
Inirekomenda
LCD Bias Generator
The TC7660SCOA generates VEE bias for character and graphic LCD displays that require a small negative rail for contrast optimization, particularly in single-supply LCD modules. Its +12V absolute maximum input supports 9V battery applications with margin, and 20 mA output is well matched to typical 1-3 mA LCD bias currents. The two-capacitor external BOM keeps the LCD module area compact and BOM cost low compared to inductive bias solutions.
Inirekomenda
Portable Instrument Power
The TC7660SCOA's 80 µA typ quiescent current and -40°C to +85°C operating range suit battery-powered portable instruments that need a negative rail from a single lithium cell stack. Its low standby consumption preserves battery life in sleep modes, and the SOIC-8 package enables compact handheld layouts. Typical use includes handheld multimeters, field data loggers, and portable medical monitoring devices requiring bipolar analog signal conditioning.
Inirekomenda
Data Acquisition System Reference
The TC7660SCOA supplies negative reference or bias rails for 16-bit and 24-bit ADCs in data acquisition systems that operate from a single positive supply. The device's lack of switching ripple above the 10 kHz fundamental makes it suitable for noise-sensitive measurement front-ends when followed by an LDO post-filter. Its 20 mA output can bias multiple reference nodes and a small instrumentation front-end simultaneously.
Inirekomenda
Voltage Doubler (Doubled Mode)
When reconfigured with pin 3 as V+ and the LV pin grounded, the TC7660SCOA operates as a voltage doubler producing +3 V to +24 V from a +1.5 V to +12 V input, useful for driving high-voltage analog switches and photo-flash capacitors in low-power circuits. The same 8-SOIC footprint and external BOM work in both inverter and doubler modes, simplifying design reuse. This mode is documented in the Microchip datasheet application section.
Inirekomenda
Buod ng mga Inirekomendang Produkto
Impormasyon ng Talumpati sa Engineering for TC7660SCOA — ikabit, gabay sa disenyo, at impormasyon ng pagsunod sa kautusan.
Paunawang Hanapin
Ikabit sa Mga Alternatibo
| Parametro | Ito ang Producto | TC7660COA | TC7660SEOA | TC7660SCOA713 | ICL7660ESA | ICL7660CBA |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Renesas Electronics | Renesas Electronics |
| Package | 8-SOIC (3.90 mm) | 8-SOIC (3.90 mm) - same | 8-SOIC (3.90 mm) - same | 8-SOIC (3.90 mm) - same | 8-SOIC (3.90 mm) - same | 8-SOIC (3.90 mm) - same |
| Input Voltage Max | +12 V | +10 V (-17%) | +12 V | +12 V | +10 V (-17%) | +10 V (-17%) |
| Output Current | 20 mA | 20 mA | 20 mA | 20 mA | 20 mA | 20 mA |
| Operating Temperature | -40 °C to +85 °C | -40 °C to +85 °C | -40 °C to +85 °C | -40 °C to +85 °C | -40 °C to +85 °C | 0 °C to +70 °C |
Pangunahing mga Pagkakaiba
- Extended +12 V input range vs original TC7660 (kumpara saTC7660COA)
- Pin-compatible with industry-standard 7660 footprint (kumpara saICL7660ESA)
- Low 80 µA quiescent current at 5 V (kumpara saICL7660CBA)
Talaan ng Disenyo
Place the 10 µF pump capacitor (C1, between pins 1 and 2) and the 10 µF reservoir capacitor (C2, between pin 3 and pin 5) as close to the IC as possible to minimize trace inductance. Keep trace length under 5 mm for both capacitors. Use a ground plane on the bottom layer to provide a low-impedance return path for the high-frequency switching currents. Avoid routing sensitive analog signals directly under the charge pump capacitors to prevent coupling.
Do not exceed the absolute maximum input of +12 V at the V+ pin. For inputs above +10 V, the LV pin (pin 4) must be left open or damage to the internal oscillator may occur. For inputs below +5 V, the LV pin must be tied to ground to enable the internal low-voltage reference. Exceeding the LV pin voltage rating is the most common failure mode reported in the field for this part family.
Estimated: At VIN = 5 V, VOUT = -5 V, and 20 mA load, the TC7660SCOA dissipates approximately 100 mW of power (P = (VIN + |VOUT|) × IOUT × (1 - η)). The 8-SOIC package has theta_JA of approximately 170 °C/W, resulting in a 17 °C junction temperature rise above ambient. No heatsink is required for normal operation, but ensure ambient temperature does not exceed +85 °C at full load.
Impormasyon ng Pagsunod sa Kautusan
RoHS compliant per Microchip product page; halogen-free status not stated in available data; not AEC-Q100 qualified (consumer/industrial grade only)
