component
MAX3237CAI+
Public Made by Adomby adom
Maxim Integrated Pre-ordered Chips, SSOP-28-208mil. Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.
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MAX3237CAI+
Maxim Integrated · Pre-ordered Chips · SSOP-28-208mil
MAX3237CAI+ from Maxim Integrated, in a SSOP-28-208mil. Pinout and pin descriptions extracted from the manufacturer datasheet (extract_pins, cross-checked by a second model); symbol, footprint, and 3D from KiCad-official CAD.
Pinout
| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | C2+ | passive | Positive terminal of the inverting charge-pump capacitor C2, which the datasheet specifies as 0.22µF to 1.0µF for the 3.0V to 5.5V range. |
| 2 | GND | power_in | Ground reference for the device. |
| 3 | C2- | passive | Negative terminal of the inverting charge-pump capacitor C2. |
| 4 | V- | power_out | Generated -5.5V charge-pump output that is pulled to ground when the device is shut down. |
| 5 | T1OUT | output | RS-232 transmitter 1 output, guaranteed at least ±5.0V into a 3kΩ load to ground and high-impedance in shutdown. |
| 6 | T2OUT | output | RS-232 transmitter 2 output, guaranteed at least ±5.0V into a 3kΩ load to ground and high-impedance in shutdown. |
| 7 | T3OUT | output | RS-232 transmitter 3 output, guaranteed at least ±5.0V into a 3kΩ load to ground and high-impedance in shutdown. |
| 8 | R1IN | input | RS-232 receiver 1 input, rated for a voltage range of ±25V. |
| 9 | R2IN | input | RS-232 receiver 2 input, rated for a voltage range of ±25V. |
| 10 | T4OUT | output | RS-232 transmitter 4 output, guaranteed at least ±5.0V into a 3kΩ load to ground and high-impedance in shutdown. |
| 11 | R3IN | input | RS-232 receiver 3 input, rated for a voltage range of ±25V. |
| 12 | T5OUT | output | RS-232 transmitter 5 output, guaranteed at least ±5.0V into a 3kΩ load to ground and high-impedance in shutdown. |
| 13 | EN | input | Receiver enable, active low; when high the inverting R_OUT outputs are put into high-impedance, and it has no effect on T_OUT. |
| 14 | SHDN | input | Shutdown control, active low; in shutdown the charge pumps are off, transmitter outputs are high-impedance and supply current is 1.0µA typical (10µA max) with SHDN = GND. |
| 15 | MBAUD | input | MegaBaud control input; connect to GND for normal 250kbps operation or to VCC for 1Mbps transmission rates. |
| 16 | R1OUTB | output | Noninverting complementary receiver 1 output that is always active, regardless of the state of EN or SHDN. |
| 17 | T5IN | input | TTL/CMOS transmitter 5 input with logic thresholds of 0.8V low and 2.0V to 2.4V high, and no internal pullup, so unused inputs must be tied to GND or VCC. |
| 18 | R3OUT | output | Inverting TTL/CMOS receiver 3 output that goes high-impedance when EN is high. |
| 19 | T4IN | input | TTL/CMOS transmitter 4 input with logic thresholds of 0.8V low and 2.0V to 2.4V high, and no internal pullup, so unused inputs must be tied to GND or VCC. |
| 20 | R2OUT | output | Inverting TTL/CMOS receiver 2 output that goes high-impedance when EN is high. |
| 21 | R1OUT | output | Inverting TTL/CMOS receiver 1 output that goes high-impedance when EN is high. |
| 22 | T3IN | input | TTL/CMOS transmitter 3 input with logic thresholds of 0.8V low and 2.0V to 2.4V high, and no internal pullup, so unused inputs must be tied to GND or VCC. |
| 23 | T2IN | input | TTL/CMOS transmitter 2 input with logic thresholds of 0.8V low and 2.0V to 2.4V high, and no internal pullup, so unused inputs must be tied to GND or VCC. |
| 24 | T1IN | input | TTL/CMOS transmitter 1 input with logic thresholds of 0.8V low and 2.0V to 2.4V high, and no internal pullup, so unused inputs must be tied to GND or VCC. |
| 25 | C1- | passive | Negative terminal of the voltage-doubler charge-pump capacitor C1. |
| 26 | VCC | power_in | Supply voltage of +3.0V to +5.5V (absolute maximum +6V). |
| 27 | V+ | power_out | Generated +5.5V charge-pump output that is pulled down to VCC when the device is shut down. |
| 28 | C1+ | passive | Positive terminal of the voltage-doubler charge-pump capacitor C1. |
Key specifications
| Parameter | Value |
|---|---|
| Manufacturer | Maxim Integrated |
| Package | SSOP-28-208mil |
| Category | Interface ICs |
| Pins | 28 |
Electrical characteristics
Limits as printed in the datasheet (page.json metadata.characteristics carries them as data).
| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| VCC Power-Supply Current | 0.5 | 2 | mA | No load, VCC = 3.3V or 5.0V, TA = +25°C | 2 | ||
| Shutdown Supply Current | 1 | 10 | µA | SHDN = GND, TA = +25°C | 2 | ||
| Input Logic Threshold Low | 0.8 | V | (Note 3) T_IN, EN, SHDN, MBAUD | 2 | |||
| Input Logic Threshold High | 2 | V | VCC = 3.3V (Note 3) | 2 | |||
| Input Logic Threshold High | 2.4 | V | VCC = 5.0V (Note 3) | 2 | |||
| Input Leakage Current | -1 | 0.01 | 1 | µA | T_IN, EN, SHDN, MBAUD | 2 | |
| Output Leakage Current | -10 | 0.05 | 10 | µA | Receivers disabled | 2 | |
| Output Voltage Low | 0.4 | V | IOUT = 1.6mA | 2 | |||
| Receiver Input Voltage Range | -25 | 25 | V | 2 | |||
| Input Threshold Low | 0.6 | 1.2 | V | TA = +25°C, VCC = 3.3V | 2 | ||
| Input Threshold Low | 0.8 | 1.5 | V | TA = +25°C, VCC = 5.0V | 2 | ||
| Input Threshold High | 1.5 | 2.4 | V | TA = +25°C, VCC = 3.3V | 2 | ||
| Input Threshold High | 1.8 | 2.4 | V | TA = +25°C, VCC = 5.0V | 2 | ||
| Input Resistance | 3 | 5 | 7 | kΩ | TA = +25°C | 3 | |
| Output Voltage Swing | 5 | 5.4 | V | All transmitter outputs loaded with 3kΩ to ground | 3 | ||
| Output Resistance | 300 | Ω | VCC = V+ = V- = 0V, VOUT = ±2V | 3 | |||
| Output Short-Circuit Current | 35 | 60 | mA | 3 | |||
| Output Leakage Current (transmitters) | -25 | 25 | µA | VOUT = ±12V, VCC = 0V or 3V to 5.5V, transmitters disabled | 3 | ||
| Maximum Data Rate | 250 | kbps | RL = 3kΩ, CL = 1000pF, one transmitter switching, MBAUD = GND | 4 | |||
| Maximum Data Rate | 1000 | kbps | VCC = 3.0V to 4.5V, RL = 3kΩ, CL = 250pF, one transmitter switching, MBAUD = VCC | 4 | |||
| Transmitter Skew | /tPHL - tPLH/ | 100 | ns | MBAUD = GND | 4 | ||
| Transmitter Skew | /tPHL - tPLH/ | 25 | ns | MBAUD = VCC | 4 | ||
| Receiver Skew | /tPHL - tPLH/ | 50 | ns | 4 | |||
| Receiver Output Enable Time | 200 | ns | Normal operation | 4 | |||
| Receiver Output Disable Time | 200 | ns | Normal operation | 4 | |||
| Transition-Region Slew Rate | 6 | 30 | V/µs | VCC = 3.3V, RL = 3Ω to 7kΩ, +3V to -3V or -3V to +3V, TA = +25°C, one transmitter switching, CL = 150pF to 1000pF, MBAUD = GND | 4 | ||
| Transition-Region Slew Rate | 24 | 150 | V/µs | VCC = 3.3V, RL = 3Ω to 7kΩ, +3V to -3V or -3V to +3V, TA = +25°C, one transmitter switching, CL = 150pF to 1000pF, MBAUD = VCC | 4 | ||
| Transition-Region Slew Rate | 4 | 30 | V/µs | VCC = 3.3V, RL = 3Ω to 7kΩ, +3V to -3V or -3V to +3V, TA = +25°C, one transmitter switching, CL = 150pF to 2500pF, MBAUD = GND | 4 | ||
| VCC Supply Voltage (absolute maximum) | VCC | -0.3 | 6 | V | 2 | ||
| V+ (absolute maximum) | V+ | -0.3 | 7 | V | Note 1 | 2 | |
| V- (absolute maximum) | V- | -7 | 0.3 | V | Note 1 | 2 | |
| V+ + V- (absolute maximum) | V+ + V- | 13 | V | Note 1 | 2 | ||
| Input Voltage T_IN, SHDN, EN (absolute maximum) | -0.3 | 6 | V | 2 | |||
| Receiver Input R_IN (absolute maximum) | R_IN | -25 | 25 | V | 2 | ||
| Transmitter Output T_OUT (absolute maximum) | T_OUT | -13.2 | 13.2 | V | 2 | ||
| Storage Temperature Range | -65 | 150 | °C | 2 | |||
| Lead Temperature | 300 | °C | Soldering, 10s | 2 | |||
| Supply Voltage (recommended operating) | VCC | 3 | 5.5 | V | Electrical characteristics test range, TA = TMIN to TMAX | 2 | |
| Operating Temperature Range (MAX32__C__ grade) | 0 | 70 | °C | C suffix (commercial) | 2 | ||
| Required Minimum Charge-Pump Capacitor C1 | C1 | 0.22 | µF | VCC = 3.0 to 5.5V, minimum required value | 9 | ||
| Required Minimum Charge-Pump Capacitors C2, C3, C4 | C2, C3, C4 | 1 | µF | VCC = 3.0 to 5.5V, minimum required value | 9 | ||
| Thermal Resistance Junction-to-Ambient θJA (single layer board) | θJA | 105 | °C/W | 28-pin SSOP, package code A28+2, single layer board | 16 | ||
| Thermal Resistance Junction-to-Case θJC (single layer board) | θJC | 24 | °C/W | 28-pin SSOP, package code A28+2, single layer board | 16 | ||
| Thermal Resistance Junction-to-Ambient θJA (multi layer board) | θJA | 67 | °C/W | 28-pin SSOP, package code A28+2, multi layer board | 16 | ||
| Thermal Resistance Junction-to-Case θJC (multi layer board) | θJC | 25 | °C/W | 28-pin SSOP, package code A28+2, multi layer board | 16 |
CAD (KiCad official)
- Symbol:
MAX3237CAI+ - Footprint:
Package_SO:SSOP-28_5.3x10.2mm_P0.65mm - 3D model: SSOP-28-208mil (KiCad packages3D, STEP)
- 3D model files:
max3237cai-etched.step/max3237cai-etched.glbcarry the MPN laser-etched on the die in a toggleableAdom.LaserEtchgroup (Fusion-ready);max3237cai.step/max3237cai.glbare the bare package body.
Provenance
Data extracted from the manufacturer datasheet, not a distributor listing:
- Datasheet: Maxim Integrated datasheet (17 pp, sha256
6179886183cdd63b, retrieved 2026-10-30, tier: manufacturer) - Extractor: parts-factory
2.0.0/extract_pins 0.3, primaryclaude-haiku-5-5(text), consensusclaude-sonnet-5-5(agreed), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish. - CAD: KiCad official libraries (CC-BY-SA 4.0).
# MAX3237CAI+
**Maxim Integrated** · Pre-ordered Chips · SSOP-28-208mil
MAX3237CAI+ from Maxim Integrated, in a SSOP-28-208mil. Pinout and pin descriptions extracted from the manufacturer datasheet (extract_pins, cross-checked by a second model); symbol, footprint, and 3D from KiCad-official CAD.
## Pinout
| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | C2+ | passive | Positive terminal of the inverting charge-pump capacitor C2, which the datasheet specifies as 0.22µF to 1.0µF for the 3.0V to 5.5V range. |
| 2 | GND | power_in | Ground reference for the device. |
| 3 | C2- | passive | Negative terminal of the inverting charge-pump capacitor C2. |
| 4 | V- | power_out | Generated -5.5V charge-pump output that is pulled to ground when the device is shut down. |
| 5 | T1OUT | output | RS-232 transmitter 1 output, guaranteed at least ±5.0V into a 3kΩ load to ground and high-impedance in shutdown. |
| 6 | T2OUT | output | RS-232 transmitter 2 output, guaranteed at least ±5.0V into a 3kΩ load to ground and high-impedance in shutdown. |
| 7 | T3OUT | output | RS-232 transmitter 3 output, guaranteed at least ±5.0V into a 3kΩ load to ground and high-impedance in shutdown. |
| 8 | R1IN | input | RS-232 receiver 1 input, rated for a voltage range of ±25V. |
| 9 | R2IN | input | RS-232 receiver 2 input, rated for a voltage range of ±25V. |
| 10 | T4OUT | output | RS-232 transmitter 4 output, guaranteed at least ±5.0V into a 3kΩ load to ground and high-impedance in shutdown. |
| 11 | R3IN | input | RS-232 receiver 3 input, rated for a voltage range of ±25V. |
| 12 | T5OUT | output | RS-232 transmitter 5 output, guaranteed at least ±5.0V into a 3kΩ load to ground and high-impedance in shutdown. |
| 13 | EN | input | Receiver enable, active low; when high the inverting R_OUT outputs are put into high-impedance, and it has no effect on T_OUT. |
| 14 | SHDN | input | Shutdown control, active low; in shutdown the charge pumps are off, transmitter outputs are high-impedance and supply current is 1.0µA typical (10µA max) with SHDN = GND. |
| 15 | MBAUD | input | MegaBaud control input; connect to GND for normal 250kbps operation or to VCC for 1Mbps transmission rates. |
| 16 | R1OUTB | output | Noninverting complementary receiver 1 output that is always active, regardless of the state of EN or SHDN. |
| 17 | T5IN | input | TTL/CMOS transmitter 5 input with logic thresholds of 0.8V low and 2.0V to 2.4V high, and no internal pullup, so unused inputs must be tied to GND or VCC. |
| 18 | R3OUT | output | Inverting TTL/CMOS receiver 3 output that goes high-impedance when EN is high. |
| 19 | T4IN | input | TTL/CMOS transmitter 4 input with logic thresholds of 0.8V low and 2.0V to 2.4V high, and no internal pullup, so unused inputs must be tied to GND or VCC. |
| 20 | R2OUT | output | Inverting TTL/CMOS receiver 2 output that goes high-impedance when EN is high. |
| 21 | R1OUT | output | Inverting TTL/CMOS receiver 1 output that goes high-impedance when EN is high. |
| 22 | T3IN | input | TTL/CMOS transmitter 3 input with logic thresholds of 0.8V low and 2.0V to 2.4V high, and no internal pullup, so unused inputs must be tied to GND or VCC. |
| 23 | T2IN | input | TTL/CMOS transmitter 2 input with logic thresholds of 0.8V low and 2.0V to 2.4V high, and no internal pullup, so unused inputs must be tied to GND or VCC. |
| 24 | T1IN | input | TTL/CMOS transmitter 1 input with logic thresholds of 0.8V low and 2.0V to 2.4V high, and no internal pullup, so unused inputs must be tied to GND or VCC. |
| 25 | C1- | passive | Negative terminal of the voltage-doubler charge-pump capacitor C1. |
| 26 | VCC | power_in | Supply voltage of +3.0V to +5.5V (absolute maximum +6V). |
| 27 | V+ | power_out | Generated +5.5V charge-pump output that is pulled down to VCC when the device is shut down. |
| 28 | C1+ | passive | Positive terminal of the voltage-doubler charge-pump capacitor C1. |
## Key specifications
| Parameter | Value |
|---|---|
| Manufacturer | Maxim Integrated |
| Package | SSOP-28-208mil |
| Category | Interface ICs |
| Pins | 28 |
## Electrical characteristics
Limits as printed in the datasheet (page.json `metadata.characteristics` carries them as data).
| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| VCC Power-Supply Current | | | 0.5 | 2 | mA | No load, VCC = 3.3V or 5.0V, TA = +25°C | 2 |
| Shutdown Supply Current | | | 1 | 10 | µA | SHDN = GND, TA = +25°C | 2 |
| Input Logic Threshold Low | | | | 0.8 | V | (Note 3) T_IN, EN, SHDN, MBAUD | 2 |
| Input Logic Threshold High | | 2 | | | V | VCC = 3.3V (Note 3) | 2 |
| Input Logic Threshold High | | 2.4 | | | V | VCC = 5.0V (Note 3) | 2 |
| Input Leakage Current | | -1 | 0.01 | 1 | µA | T_IN, EN, SHDN, MBAUD | 2 |
| Output Leakage Current | | -10 | 0.05 | 10 | µA | Receivers disabled | 2 |
| Output Voltage Low | | | | 0.4 | V | IOUT = 1.6mA | 2 |
| Receiver Input Voltage Range | | -25 | | 25 | V | | 2 |
| Input Threshold Low | | 0.6 | 1.2 | | V | TA = +25°C, VCC = 3.3V | 2 |
| Input Threshold Low | | 0.8 | 1.5 | | V | TA = +25°C, VCC = 5.0V | 2 |
| Input Threshold High | | 1.5 | 2.4 | | V | TA = +25°C, VCC = 3.3V | 2 |
| Input Threshold High | | 1.8 | 2.4 | | V | TA = +25°C, VCC = 5.0V | 2 |
| Input Resistance | | 3 | 5 | 7 | kΩ | TA = +25°C | 3 |
| Output Voltage Swing | | 5 | 5.4 | | V | All transmitter outputs loaded with 3kΩ to ground | 3 |
| Output Resistance | | 300 | | | Ω | VCC = V+ = V- = 0V, VOUT = ±2V | 3 |
| Output Short-Circuit Current | | 35 | 60 | | mA | | 3 |
| Output Leakage Current (transmitters) | | -25 | | 25 | µA | VOUT = ±12V, VCC = 0V or 3V to 5.5V, transmitters disabled | 3 |
| Maximum Data Rate | | 250 | | | kbps | RL = 3kΩ, CL = 1000pF, one transmitter switching, MBAUD = GND | 4 |
| Maximum Data Rate | | 1000 | | | kbps | VCC = 3.0V to 4.5V, RL = 3kΩ, CL = 250pF, one transmitter switching, MBAUD = VCC | 4 |
| Transmitter Skew | /tPHL - tPLH/ | | | 100 | ns | MBAUD = GND | 4 |
| Transmitter Skew | /tPHL - tPLH/ | | | 25 | ns | MBAUD = VCC | 4 |
| Receiver Skew | /tPHL - tPLH/ | | | 50 | ns | | 4 |
| Receiver Output Enable Time | | | | 200 | ns | Normal operation | 4 |
| Receiver Output Disable Time | | | | 200 | ns | Normal operation | 4 |
| Transition-Region Slew Rate | | 6 | | 30 | V/µs | VCC = 3.3V, RL = 3Ω to 7kΩ, +3V to -3V or -3V to +3V, TA = +25°C, one transmitter switching, CL = 150pF to 1000pF, MBAUD = GND | 4 |
| Transition-Region Slew Rate | | 24 | | 150 | V/µs | VCC = 3.3V, RL = 3Ω to 7kΩ, +3V to -3V or -3V to +3V, TA = +25°C, one transmitter switching, CL = 150pF to 1000pF, MBAUD = VCC | 4 |
| Transition-Region Slew Rate | | 4 | | 30 | V/µs | VCC = 3.3V, RL = 3Ω to 7kΩ, +3V to -3V or -3V to +3V, TA = +25°C, one transmitter switching, CL = 150pF to 2500pF, MBAUD = GND | 4 |
| VCC Supply Voltage (absolute maximum) | VCC | -0.3 | | 6 | V | | 2 |
| V+ (absolute maximum) | V+ | -0.3 | | 7 | V | Note 1 | 2 |
| V- (absolute maximum) | V- | -7 | | 0.3 | V | Note 1 | 2 |
| V+ + V- (absolute maximum) | V+ + V- | | | 13 | V | Note 1 | 2 |
| Input Voltage T_IN, SHDN, EN (absolute maximum) | | -0.3 | | 6 | V | | 2 |
| Receiver Input R_IN (absolute maximum) | R_IN | -25 | | 25 | V | | 2 |
| Transmitter Output T_OUT (absolute maximum) | T_OUT | -13.2 | | 13.2 | V | | 2 |
| Storage Temperature Range | | -65 | | 150 | °C | | 2 |
| Lead Temperature | | | | 300 | °C | Soldering, 10s | 2 |
| Supply Voltage (recommended operating) | VCC | 3 | | 5.5 | V | Electrical characteristics test range, TA = TMIN to TMAX | 2 |
| Operating Temperature Range (MAX32__C__ grade) | | 0 | | 70 | °C | C suffix (commercial) | 2 |
| Required Minimum Charge-Pump Capacitor C1 | C1 | 0.22 | | | µF | VCC = 3.0 to 5.5V, minimum required value | 9 |
| Required Minimum Charge-Pump Capacitors C2, C3, C4 | C2, C3, C4 | 1 | | | µF | VCC = 3.0 to 5.5V, minimum required value | 9 |
| Thermal Resistance Junction-to-Ambient θJA (single layer board) | θJA | | 105 | | °C/W | 28-pin SSOP, package code A28+2, single layer board | 16 |
| Thermal Resistance Junction-to-Case θJC (single layer board) | θJC | | 24 | | °C/W | 28-pin SSOP, package code A28+2, single layer board | 16 |
| Thermal Resistance Junction-to-Ambient θJA (multi layer board) | θJA | | 67 | | °C/W | 28-pin SSOP, package code A28+2, multi layer board | 16 |
| Thermal Resistance Junction-to-Case θJC (multi layer board) | θJC | | 25 | | °C/W | 28-pin SSOP, package code A28+2, multi layer board | 16 |
## CAD (KiCad official)
- Symbol: `MAX3237CAI+`
- Footprint: `Package_SO:SSOP-28_5.3x10.2mm_P0.65mm`
- 3D model: SSOP-28-208mil (KiCad packages3D, STEP)
- 3D model files: `max3237cai-etched.step` / `max3237cai-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `max3237cai.step` / `max3237cai.glb` are the bare package body.
## Provenance
Data extracted from the manufacturer datasheet, not a distributor listing:
- **Datasheet:** [Maxim Integrated datasheet](https://www.analog.com/media/en/technical-documentation/data-sheets/max3222-max3241.pdf) (17 pp, sha256 `6179886183cdd63b`, retrieved 2026-10-30, tier: manufacturer)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-haiku-5-5` (text), consensus `claude-sonnet-5-5` (agreed), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish.
- **CAD:** KiCad official libraries (CC-BY-SA 4.0).
[Datasheet PDF](docs/max3237cai-datasheet.pdf)