API · /transistor-api

BJT Transistor API

healthy 4,994 Subscribers

Bipolar-junction-transistor (BJT) circuit maths as an API, computed locally and deterministically. The currents endpoint relates the three terminal currents through the DC current gain β (hFE): the collector current Ic = β·Ib, the emitter current Ie = (β+1)·Ib and the common-base gain α = β/(β+1) ≈ 1, from β and any one current. The bias endpoint analyses the operating point of the classic voltage-divider bias network — from the supply voltage, the two divider resistors, the collector and emitter resistors, β and the base-emitter drop it computes the Thévenin equivalent (Vth = Vcc·R2/(R1+R2), Rth = R1‖R2), the base current Ib = (Vth − Vbe)/(Rth + (β+1)·Re), the collector and emitter currents, the collector-emitter voltage Vce and the node voltages, and classifies the operating region as cutoff, active or saturation. The power endpoint computes the transistor's power dissipation, Pd ≈ Vce·Ic (plus Vbe·Ib), to check it against the rated maximum. Currents are in amperes, resistances in ohms and voltages in volts, with Vbe defaulting to 0.7 V for silicon. Everything is computed locally and deterministically, so it is instant and private. Ideal for electronics, amplifier-design, embedded and hobbyist app developers, biasing and operating-point tools, and electronics education. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is BJT biasing; for op-amp circuits use an op-amp API and for an LED series resistor an LED-resistor API.

#transistor #bjt #biasing #electronics #amplifier #developer-tools

api.oanor.com/transistor-api

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Machine-readable spec so AI agents can integrate this API.

/api/transistor-api/openapi.json

/api/transistor-api/llms.txt

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API health

healthy

Uptime: 100.00%; Server probes · 24h
Avg latency: 115 ms; Server probes · 24h
Subscribers: 4,994; active
Total calls: 4; last 7 days

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Pricing

Pick a tier — billed monthly, cancel anytime.

Free

2,580 calls / month
2 requests / second
Hard cap (429 above quota, no overage)
2,580 calls/month
2 req/sec
Currents + bias + power
No credit card

Starter

€8.00 /month

39,200 calls / month
6 requests / second
Hard cap (429 above quota, no overage)
39,200 calls/month
6 req/sec
Operating point, region, α
Email support

Pro

€21.00 /month

253,000 calls / month
15 requests / second
Hard cap (429 above quota, no overage)
253,000 calls/month
15 req/sec
Amplifier & embedded pipelines
Priority support

Mega

€65.00 /month

1,640,000 calls / month
40 requests / second
Hard cap (429 above quota, no overage)
1,640,000 calls/month
40 req/sec
Platform scale
Dedicated SLA

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Related APIs

Other APIs with overlapping tags.

Voltage Divider API

Resistive voltage-divider circuit design as an API, computed locally and deterministically. The divide endpoint takes an input voltage and two resistors and returns the output voltage Vout = Vin·R2/(R1+R2), the current I = Vin/(R1+R2) that flows through the chain, and the power dissipated in each resistor and in total — a 12 V source with R1 = 1 kΩ and R2 = 2 kΩ gives 8 V at 4 mA. The loaded endpoint adds a load resistor across R2, computes the parallel combination R2′ = R2·RL/(R2+RL) and the loaded output Vout = Vin·R2′/(R1+R2′), and reports the droop in volts and percent against the unloaded value, the classic mistake when a divider feeds a real load. The resistor endpoint sizes the missing resistor for a target output — R2 = R1·Vout/(Vin−Vout) or R1 = R2·(Vin−Vout)/Vout — so you can pick parts for a reference or sensor-bias point. All quantities are volts, ohms, amps and watts. Everything is computed locally and deterministically, so it is instant and private. Ideal for electronics, embedded, hardware, sensor-interfacing and EE-education app developers, reference-voltage and bias-network tools, and maker software. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is the resistive divider; for a single Ohm’s-law relationship use an Ohm’s-law API and for RC/RL filters an RC-filter API.

api.oanor.com/voltagedivider-api

RC Filter API

First-order RC and RL passive-filter design as an API, computed locally and deterministically. The lowpass and highpass endpoints take a resistor and capacitor (RC) or a resistor and inductor (RL) and return the −3 dB cutoff frequency (fc = 1/(2πRC) for RC, R/(2πL) for RL), the time constant (τ = RC or L/R) and the angular cutoff; pass a frequency as well and they add the magnitude response as a linear gain and in decibels and the phase shift in degrees — a 1 kΩ / 1 µF low-pass has fc ≈ 159.15 Hz, and right at the cutoff the gain is −3.01 dB with −45° phase for a low-pass or +45° for a high-pass. The component endpoint solves the missing one of fc, R and C from the other two (fc = 1/(2πRC)), so you can size a resistor or capacitor for a target cutoff. All quantities are SI: ohms, farads, henries and hertz. Everything is computed locally and deterministically, so it is instant and private. Ideal for electronics, audio, embedded, signal-processing and EE-education app developers, filter-design and circuit-sizing tools, and maker software. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is first-order single-pole filter design; for full RLC impedance and resonance use an impedance API and for stored capacitor energy a capacitor API.

api.oanor.com/rcfilter-api

Chebyshev Filter API

Chebyshev Type I filter-design maths as an API, computed locally and deterministically. The order endpoint computes the minimum filter order to meet a specification, n = ⌈acosh(√((10^(As/10)−1)/(10^(Ap/10)−1))) / acosh(fs/fp)⌉, from the passband edge frequency and its ripple and the stopband edge and its required attenuation — a Chebyshev filter usually needs a lower order than a Butterworth for the same specification, trading a flat passband for equiripple. The response endpoint computes the equiripple magnitude response, |H| = 1/√(1 + ε²·Tₙ²(f/fc)) with the ripple factor ε = √(10^(Ap/10) − 1) and the Chebyshev polynomial Tₙ, in linear and decibel form — in the passband the magnitude ripples between 0 and −Ap dB and reaches exactly −Ap dB at the cutoff, then rolls off faster than a Butterworth. The ripple endpoint converts between the passband ripple in decibels and the ripple factor ε, with the passband maximum and minimum. Frequencies are in hertz, ripple and attenuation in decibels and the order a positive integer. Everything is computed locally and deterministically, so it is instant and private. Ideal for DSP, audio, RF, communications and instrumentation app developers, filter-design and selectivity tools, and signal-processing education. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is the Chebyshev Type I filter; for the maximally-flat Butterworth use a Butterworth API.

api.oanor.com/chebyshev-api

Butterworth Filter API

Butterworth-filter design maths as an API, computed locally and deterministically. The order endpoint computes the minimum filter order needed to meet a specification — from the passband edge frequency and its allowed ripple and the stopband edge frequency and its required attenuation it returns the exact and rounded-up order, n = ⌈log10((10^(As/10)−1)/(10^(Ap/10)−1)) / (2·log10(fs/fp))⌉, where each extra order adds 20 dB per decade of roll-off. The response endpoint computes the maximally-flat magnitude response of an n-th order Butterworth filter at a frequency, |H| = 1/√(1 + (f/fc)^(2n)), in linear and decibel form with the attenuation and the asymptotic roll-off — the response is exactly −3.01 dB at the cutoff for any order. The poles endpoint gives the s-plane pole locations, equally spaced on a circle of radius ωc in the left half-plane at angles π·(2k+n−1)/(2n), all stable. Frequencies are in hertz (or any consistent unit), ripple and attenuation in decibels and the order a positive integer. Everything is computed locally and deterministically, so it is instant and private. Ideal for DSP, audio, RF, instrumentation and embedded app developers, anti-aliasing and filter-design tools, and signal-processing education. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is the Butterworth filter; for a single-pole RC cutoff and resonance use a resonance API and for AC impedance an impedance API.

api.oanor.com/butterworth-api

Frequently asked questions

Quick answers about pricing, quotas, and integration.

How do I get an API key for BJT Transistor API?

Sign up for free at oanor.com, generate an API key from the developer dashboard, and call BJT Transistor API with the x-oanor-key header. No credit card needed for the free tier.

What's the rate limit for BJT Transistor API?

Free tier allows 1 request per second. Paid plans scale up to 50 requests per second on the Mega tier. Hard limits return HTTP 429 above the quota — no surprise overage charges.

How much does BJT Transistor API cost?

BJT Transistor API has a free tier with 100 calls / month. Paid plans start at €8.00 / month with higher quotas and faster rate limits.

Can I cancel my subscription anytime?

Yes. Plans are billed monthly and you can cancel anytime from your billing dashboard. No long-term contracts and no cancellation fee.

Is BJT Transistor API GDPR-compliant?

All requests to BJT Transistor API go through our EU-based gateway. Your upstream API key never leaves our server and no personal data is shared with the upstream provider beyond the request you send.

Transistor 3

Meta 1

Pick an endpoint from the list on the left to see its details and try it.

GET /v1/bias

Voltage-divider bias

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GET /v1/currents

BJT currents

Playground

Parameters

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GET /v1/power

Power dissipation

Playground

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GET /v1/meta

Spec

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Code snippets

curl https://api.oanor.com/transistor-api/SOME_PATH \
  -H "x-oanor-key: oanor_test_..."

const res = await fetch("https://api.oanor.com/transistor-api/SOME_PATH", {
  headers: { "x-oanor-key": "oanor_test_..." }
});
const data = await res.json();

$ch = curl_init("https://api.oanor.com/transistor-api/SOME_PATH");
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_HTTPHEADER, ["x-oanor-key: oanor_test_..."]);
$response = curl_exec($ch);

import requests
r = requests.get(
    "https://api.oanor.com/transistor-api/SOME_PATH",
    headers={"x-oanor-key": "oanor_test_..."},
)
print(r.json())

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BJT Transistor API

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Related APIs

Voltage Divider API

RC Filter API

Chebyshev Filter API

Butterworth Filter API

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