Anasys Semiconductor, Inc. MAX3222E/3232E High ESD-Protected, Low Power, 3.0V to 5.5V, Single Supply RS-232 Transceivers General Description The MAX3222E/M AX3232E are 2 driver, 2 receiver RS-232 transceiver solutions intended for portable or hand-held applications, features low power consumption, high data-rate capabilities, and enhanced ESD protection. The ESD tolerance of the MAX3222E/3232E devices is over ±15kV for both human body model and IEC1000-4-2 air discharge test methods. A low-dropout transmitter output stage delivers true RS-232 performance from a +3.0V to +5.5V power supply, using an internal dual charge pump. The charge pump requires only four small 0.1µF capacitors for operation from a +3.3V supply. Each device guarantees operation at data rates of 250kbps while maintaining RS-232 output levels. The MAX3222E features a 1µA shutdown mode that reduces power consumption in battery-powered portable systems. The M AX3222E receivers remain active in shutdown mode, allowing monitoring of external devices while consuming only 1µA of supply current. The M AX3222E and MAX3232E are pin, package, and functionally compatible with the industry-standard M AX242 and MAX232, respectively. Applications Notebook, Sub notebook, and Palmtop Computers Battery-Powered / Hand-Held Equipment POS terminal / Intelligent Network Switch DMM / Printers Smart Phones xDSL Modems Features Meets true EIA/TIA-232-F Standards from a +3.0V to +5.5V power supply Interoperable with EIA/TIA - 232 and adheres to EIA/TIA - 562 1µA Low-Power Shutdown (MAX3222E) Enhanced ESD Specifications: 15kV Human Body Model 15kV IEC1000-4-2 Air Discharge 8kV IEC1000-4-2 Contact Discharge 250 kbps Minimum Transmission Rate Ideal for Handheld, Battery Operated Applications Latch up Free Guaranteed 30V/µs Max Slew Rate BiCMOS Technology MAX3222/3232 Datasheet Rev. 0.1 , Sept 2005 Page 1 of 7 Anasys Semiconductor, Inc. Ordering Information PART TEMP. RANGE PIN-PACKAGE MAX3222EEUP -40°C to +85°C 20 TSSOP MAX3222EEAP -40°C to +85°C 20 SSOP MAX3222EEPN -40°C to +85°C 18 Plastic DIP MAX3232EEAE -40°C to +85°C 16 SSOP MAX3232EESE -40°C to +85°C 16 Narrow SO MAX3232EEPE -40°C to +85°C 16 Plastic DIP MAX3232EEUP -40°C to +85°C 20 TSSOP Absolute Maximum Ratings Ratings Range Units VCC to GND -0.3 to +6 V V+ to GND -0.3 to +7 V V- to GND -0.3 to +7 V V+ to V- 13 V -0.3 to +6 V ±25 V T_OUT to GND ±13.2 V R_OUT to GND -0.3 to (VCC+0.3 ) V Short-Circuit Duration, T_OUT Continuous Power Supply Input Voltages T_IN, EN , SHDN R_IN to GND Output Voltages Continuous Power Dissipation (TA = +70°C) 16-Pin DIP (derate 10.53mW/°C above +70°C) 842 mW 16-Pin NSO (derate 8.70mW/°C above +70°C) 696 mW 16-Pin SSOP (derate 7.14 mW/°C above +70°C) 571 mW 20-Pin TSSOP (derate 10.9 mW/°C above +70°C) 879 mW 20-Pin SSOP (derate 8.00 mW/°C above +70°C) 640 mW Operating Temperature Ranges MAX32__EC__ MAX32__EE__ Storage Temperature Range 0 to 70 -40 to +85 -65 to +165 °C °C °C Lead 300 °C Temperature (soldering, 10sec) Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. MAX3222/3232 Datasheet Rev. 0.1 , Sept 2005 Page 2 of 7 Anasys Semiconductor, Inc. Pin Description PIN MAX3222E SO/DIP TSSOP/SSOP MAX3232E SO/DIP/SSOP TSSOP NAME FUNCTION Receiver Enable. Active low. 1 1 — — EN 2 2 1 2 C1+ 3 3 2 3 V+ 4 4 3 4 C1- 5 5 4 5 C2+ 6 6 5 6 C2- Negative Terminal of Inverting Charge-Pump Capacitor 7 7 6 7 V- -5.5V Generated by the Charge Pump 8, 15 8, 17 7, 14 8, 17 T_OUT RS-232 Transmitter Outputs 9, 14 9, 16 8, 13 9, 16 R_IN RS-232 Receiver Inputs 10, 13 10, 15 9, 12 12, 15 R_OUT TTL/CMOS Receiver Outputs 11, 12 12, 13 10, 11 13, 14 T_IN TTL/CMOS Transmitter Inputs 16 18 15 18 GND Ground 17 19 16 19 VCC +3.0V to +5.5V Supply Voltage 18 20 — — SHDN Shutdown Control. Active low. MAX3222/3232 Datasheet Rev. 0.1 , Sept Positive Terminal of Voltage-Doubler Charge-Pump Capacitor +5.5V Generated by the Charge Pump Negative Terminal of Voltage-Doubler Charge-Pump Capacitor Positive Terminal of Inverting Charge-Pump Capacitor Page 3 of 7 Anasys Semiconductor, Inc. Electrical Characteristics (VCC = +3V to +5.5V, C1-C4 = 0.1µF, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) Parameter Symbol Conditions Min DC Characteristics (VCC = +3.3V or +5.5V, TA = +25°C ) VCC Supply Current Shutdown Current Supply Typ Max Units ICC SHDN = VCC Load, TA=+25°C ,No 0.3 1 mA ISHDN SHDN =GND, Load, TA=+25°C No 1 10 µA Logic Input Current Leakage T_IN, SHDN , EN ±1 µA 0.8 V Input Threshold Low VIL T_IN, SHDN , EN Input Threshold High VIH Output Voltage Low Output Voltage High VOH VOL T_IN, SHDN , EN R_OUT; IOUT=3.2mA R_OUT; IOUT=-1.0mA 2.0 VCC-0.6 V 0.4 V V 25 V V V V kΩ VCC-0.1 EIA/TIA-232E Receiver Inputs Input Voltage Range Input Threshold Low Input Threshold High Input Hysteresis Input Resistance TA=+25°C, VCC= 3.3V TA=+25°C, VCC= 3.3V VCC= 3.3V TA=+25°C, VCC= 3.3V -25 0.6 1.1 1.5 2.4 0.2 7 0.1 3 5 ±5 ±5.4 V 300 500 Ω EIA/TIA-232E Transmitter Outputs All drivers loaded with 3kΩ to ground Output Voltage Swing Output Resistance Output Short Circuit Current ±60 mA TIMING CHARACTERISTICS RL=3 kΩ to 7 kΩ, CL= 50pF to 1000pF, one transmitter switching Maximum Data Rate Receiver Propagation Delay Transmitter Propagation Delay tPLHR, tPHLR tPLHT, tPHLT Transition-Region Slew rate 250 CL= 150pF RL=3 kΩ, CL= 2500pF all transmitters loaded TA=+25°C, VCC= 3.3V RL=3 kΩ to 7 kΩ, CL= 50pF to 1000pF, measured from -3V to +3V or +3V to -3V, 3 kbps 0.15 µs 0.1 µs 6 30 V/µs ESD & Latch up Performance ESD Voltage Protection Latch Performance Human Body Model IEC1000-4-2, Contact Discharge IEC1000-4-2, Air-Gap Discharge up MAX3222/3232 Datasheet Rev. 0.1 , Sept 2005 ±15 kV ±8 kV ±15 kV ±200 mA Page 4 of 7 Anasys Semiconductor, Inc. Typical Operating Characteristics (VCC = +3.3V, 250kbps data rate, 0.1µF capacitors, all transmitters loaded with 3kΩ and CL, TA = +25°C, unless otherwise noted.) UM3222E/3232E OPERATION SUPPLY CURRENT VS.LOAD CAPACITANCE UM3222E/3232E SLEW RATE VS.LOAD CAPACITANCE 16 6 5 4 3 2 1 0 -1 -2 -3 -4 -5 -6 14 T1 TRANSMITTING AT 250kbps T2 TRANSMITTING AT 15.6kbps 12 SUPPLY CURRENT (mA) SLEW RATE (V/us) TRANSMITTER OUTPUT VOLATGE (V) UM3222E/3232E TRANSMITTER OUTPUT VOLTAGE VS.LOAD CAPACITANCE 10 8 6 4 2 0 0 1000 2000 3000 4000 5000 0 1000 LOAD CAPACITANCE(pF) 2000 3000 4000 45 40 35 30 25 20 15 10 5 0 0 5000 1000 2000 3000 4000 5000 LOAD CAPACITANCE(pF) LOAD CAPACITANCE(pF) Typical Operating Circuits +3.3V +3.3V CBYPASS 2 C1 17 VCC C1+ V+ 3 1 C1 4 5 C1C2+ C2 CBYPASS 6 C2- C3 UNION MAX3222E V- 16 VCC C1+ 4 C2 2 C3 3 C1C2+ 7 V+ 5 C2- UNION MAX3232E V- 6 C4 C4 12 T1IN T1OUT 15 11 T1IN T1OUT 14 11 T2IN T2OUT 8 10 T2IN T2OUT 7 13 R1OUT R1IN 14 12 R1OUT R1IN 13 10 R2OUT R2IN 9 9 R2OUT R2IN 8 SHDN 18 1 EN GND 16 MAX3222/3232 Datasheet Rev. 0.1 , Sept GND 15 Page 5 of 7 Anasys Semiconductor, Inc. Detailed Description Dual Charge-Pump Voltage Converter The MAX3222E/MAX3232Es’ internal power supply consists of a regulated dual charge pump that provides output voltages of +5.5V (doubling charge pump) and -5.5V (inverting charge pump) over the +3.0V to +5.5V VCC range. The charge pump operates in discontinuous mode; if the output voltages are less than 5.5V, the charge pump is enabled, and if the output voltages exceed 5.5V, the charge pump is disabled. Each charge pump requires a flying capacitor (C1, C2) and a storage capacitor (C3, C4) to generate the V+ and V- supplies. RS-232 Transmitters The transmitters are inverting level translators that convert TTL/CMOS-logic levels to ±5V EIA/TIA-232 compliant levels. The MAX3222E/MAX3232E transmitters guarantee a 250kbps data rate with worst-case loads of 3KΩ parallel with 1000pF. Transmitters can be paralleled to drive multiple receivers. The MAX3222E transmitters are disabled and the outputs are forced into a high-impedance state when the device is in shutdown mode ( SHDN = GND). The MAX3222E/MAX3232E permits the outputs to be driven up to ±12V in shutdown. RS-232 Receivers The receivers convert RS-232 signals to CMOS-logic output levels. The MAX3222E receivers have inverting three-state outputs. Drive EN high to place the receiver(s) into a high impedance state. Receivers can be either active or inactive in shutdown. MAX3222E Supply current falls to less than 1µA in shutdown mode ( SHDN = GND). When shutdown, the device’s charge pumps are shut off, V+ is pulled down to VCC, V- is pulled to ground, and the transmitter outputs are disabled (high impedance). The time required to recover from shutdown is typically 100µs. Connect SHDN to VCC if shutdown mode is not used. ±15kV ESD Protection ESD-protection structures are incorporated to protect against electrostatic discharges encountered during handling and assembly. The driver outputs and receiver inputs of the MAX3222E/MAX3232E have extra protection against static electricity. The ESD structures withstand high ESD in all states: normal operation, shutdown, and powered down. After an ESD event, Circuits keep working without latch up. ESD protection can be tested in various ways; the transmitter outputs and receiver inputs for the MAX3222E/MAX3232E are characterized for protection to the following limits: • ±15kV using the Human Body Model • ±8kV using the Contact Discharge method specified in IEC 1000-4-2 • ±15kV using the Air-Gap Discharge method specified in IEC 1000-4-2 MAX3222/3232 Datasheet Rev. 0.1 , Sept. 2005 Page 6 of 7 Anasys Semiconductor, Inc. Application Information Capacitor Selection The capacitor type used for C1–C4 is not critical for proper operation; polarized or non-polarized capacitors can be used. The charge pump requires 0.1µF capacitors for 3.3V operation. Increasing the capacitor values (e.g., by a factor of 2) reduces ripple on the transmitter outputs and slightly reduces power consumption. C2, C3, and C4 can be increased without changing C1’s value. When using the minimum required capacitor values, make sure the capacitor value does not degrade excessively with temperature. If in doubt, use capacitors with a larger nominal value. The capacitor’s equivalent series resistance (ESR), which usually rises at low temperatures, influences the amount of ripple on V+ and V- output voltages. Power-Supply Decoupling In most circumstances, a 0.1µF VCC bypass capacitor is adequate. In applications sensitive to power-supply noise, use a capacitor of the same value as charge pump capacitor C1. Connect bypass capacitors as close to the IC as possible. Operation Down to 2.7V Transmitter outputs meet EIA/TIA-562 levels of ±3.7V with supply voltages as low as 2.7V. Transmitter Outputs Recovering from Shutdown When MAX3222E’s two transmitter outputs were recovering from shutdown mode, the two transmitter outputs are shown going to opposite RS-232 levels (one transmitter input is high; the other is low) as they become active. Each transmitter is loaded with 3K resistor in parallel with 2500pF. The transmitter outputs display no ringing or undesirable transients as they come out of shutdown. Note that the transmitters are enabled only when the magnitude of V- exceeds approximately -3.0V. Interconnection with 3V and 5V Logic The MAX3222E/MAX3232E can directly interface with various 3V and 5V logic families, including ACT and HCT CMOS. MAX3222/3232 Datasheet Rev. 0.1 , Sept. 2005 Page 7of 7