STC International Limited http://www.mcu-memory.com STC232E High ESD-Protected, Fail-Safe , Single Supply RS-232 Transceivers General Description The STC232E is low power single supply RS232 interface. The device consists of two line drivers, two line receivers, and dual charge pump circuit. The device meets the requirements of TIA/EIA-232 standard and provides the electrical interface between an asynchronous communication controller and the serial-port connector. The on chip charge pump and four small external capacitors act as onboard DC to DC converter, allow chip operated from single 5V supply, eliminating the need for ±10V power supplies, reduce cost and board space. Chip power supply current is specified at 8.0 mA maximum, making the device ideal for battery and power conscious applications. The device operates at data signaling rates over 120Kb/s. The slew rate of driver is set internally less than 30V/µs and the receivers feature internal noise filtering, eliminating the need for external slew rate and filter capacitors for reliable operation. The driver inputs and receiver outputs are TTL and CMOS compatible. STC232E comes in 16 pin DIP, SOP and SSOP packages, operating over the commercial and industrial temperature ranges. The ESD tolerance has been upgraded on these devices to over ±15KV for both Human Body Model and IEC1000-4-2 Air Discharge Method, without latchup. These devices are pin-to-pin compatible with MAX202/232 devices as well as other popular industry standards. Applications Notebook, Subnotebook, and Palmtop Computers Battery-Powered Equipment Hand-Held Equipment POS terminal Features ESD Protection for RS-232 Bus Pins up to ±15kV Human Body Model Meets or Exceeds the Requirements of TIA/EIA-232-F and ITU V.28 Standards Single +5V power supply Low power, ICC 8.0mA maximum Operates up to 120 Kbit/s BiCMOS Technology Receiver Noise Filter Latch-Up Performance Exceeds 200mA Pin compatible with industry standard MAX232, ICL232 Ordering Information PART TEMP. RANGE PIN-PACKAGE STC232EESE -40°C to +85°C 16 Plastic DIP STC232EEPE -40°C to +85°C 16 Narrow SO STC232E Datasheet Rev.0.1, Dec.2005 Page １ of 6 STC International Limited http://www.mcu-memory.com Absolute Maximum Ratings VCC… … … … … … … … … … … … … … … … … … … … … … -0.3V to +6V V+ … … … … … … … … … … … … … … … … … … … (VCC - 0.3V) to +14V V- … … … … … … … … … … … … … … … … … … … … … … -14V to +0.3V Input Voltages T_IN… … … … … … … … … … … … … … … … … -0.3V to (V+ + 0.3V) R_IN… … … … … … … … … … … … … … … … … … … … … … … ±30V Output Voltages T_OUT… … … … … … … … … … … … … (V- - 0.3V) to (V+ + 0.3V) Short-Circuit Duration, T_OUT… … … … … … … … … … … … Continuous Continuous Power Dissipation (TA = +70°C) 16-Pin Plastic DIP (derate 10.53mW/°C above +70°C) … … 842mW 16-Pin Narrow SO (derate 8.70mW/°C above +70°C) … … 696mW Operating Temperature Ranges STC232E… … … … … … … … … … … … … … … … … -40°C to +85°C Storage Temperature Range… … … … … … … … … -65°C to +165°C Lead Temperature (soldering, 10sec) … … … … … … … … … +300°C R_OUT… … … … … … … … … … … … … … … -0.3V to (VCC + 0.3V) 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. Electrical Characteristics (VCC = +5V ±10% for STC232E; C1～C4 = 0.1µF; TA = TMIN to TMAX; unless otherwise noted. Typical values are at TA = +25°C.) PARAMETER DC CHARACTERISTICS VCC Supply Current LOGIC Input Leakage Current Input Threshold Low Input Threshold High SYMBOL ICC CONDITIONS No load, TA = +25°C MIN STC232E VIL VIH T_IN = 0V to VCC T_IN T_IN VOL R_OUT; IOUT = 3.2mA Output Voltage High VOH Output Leakage Current EIA/TIA-232E RECEIVER INPUTS Input Voltage Range R_OUT; IOUT = -1.0mA 0V = ROUT = VCC Output Voltage Low TA = +25°C, VCC = 5V Input Threshold High TA = +25°C, VCC = 5V Output Voltage Swing Output Resistance Output Short-Circuit Current TIMING CHARACTERISTICS Normal operation Normal operation VCC = 5V TA = +25°C, VCC = 5V All drivers loaded with 3k? to ground (Note 1) VCC = V+ = V- = 0V, VOUT = ±2V MAX 6 3.5 V CC-0.4 ±0.05 0.8 mA ±10 0.8 µA V V 0.4 V ±10 V µA 30 V 1.2 V 1.7 2.4 V 0.2 3 0.5 5 1.0 7 V k? ±5 ±9 V 300 RL = 3k? to 7k? , CL = 50pF to 1000pF, 120 one transmitter switching All parts, normal Receiver Propagation Delay tPLHR, tPHLR CL = 150pF operation RL = 3k? , CL = 2500pF, Transmitter Propagation Delay tPLHT, tPHLT all transmitters loaded TA = +25°C, VCC = 5V, RL = 3k? to 7k? , Transition-Region Slew Rate CL = 50pF to 1000pF, measured from 3 -3V to +3V or +3V to -3V, Figure 1 ESD PERFORMANCE: TRANSMITTER OUTPUTS, RECEIVER INPUTS Human Body Model ESD-Protection Voltage IEC1000-4-2, Contact Discharge IEC1000-4-2, Air-Gap Discharge ±10 ±60 Maximum Data Rate STC232E Datasheet Rev.0.1, Dec.2005 UNITS 8 2.0 -30 Input Threshold Low Input Hysteresis Input Resistance EIA/TIA-232E TRANSMITTER OUTPUTS TYP ? mA kbps 0.5 10 µs 2 6 µs 30 ±15 ±8 ±15 V/µs kV Page ２ of 6 STC International Limited http://www.mcu-memory.com Pin Configurations Ｃ１＋ １ １６ Ｖｃｃ Ｖ＋ ２ １５ ＧＮＤ Ｃ１－ ３ １４ Ｔ１ＯＵＴ Ｃ２＋ ４ ＳＴＣ２３２Ｅ １３ Ｒ１ＩＮ Ｃ２－ ５ １２ Ｒ１ＯＵＴ Ｖ－ ６ １１ Ｔ１ＩＮ Ｔ２ＯＵＴ ７ １０ Ｔ２ＩＮ Ｒ２ＩＮ ８ ９ Ｒ２ＯＵＴ ＤＩＰ／ＳＯ Pin Descriptions PIN DIP/SO/SSOP 1,3 2 4,5 6 7,14 8,13 9,12 10,11 15 16 NAME FUNCTION C1+, C1V+ C2+, C2VT_OUT R_IN R_OUT T_IN GND VCC Terminals for positive charge-pump capacitor +2VCC voltage generated by the charge pump Terminals for negative charge-pump capacitor -2VCC voltage generated by the charge pump RS-232 Driver Outputs RS-232 Receiver Inputs RS-232 Receiver Outputs RS-232 Driver Inputs Ground +4.5V to +5.5V Supply-Voltage Input Typical Operating Characteristics ＴＲＡＮＳＭＩＴＴＥＲ ＳＬＥＷ ＲＡＴＥ ｖｓ．ＬＯＡＤ ＣＡＰＡＣＩＴＡＮＣＥ ＴＲＡＮＳＭＩＴＴＥＲ ＯＵＴＰＵＴ ＶＯＬＴＡＧＥ ｖｓ．ＬＯＡＤ ＣＡＰＡＣＩＴＡＮＣＥ １４ ８．０ ＡＬＬ ＴＲＡＮＳＭＩＴＴＥＲＳ ＬＯＡＤＥＤ ＤＡＴＡ ＲＡＴＥ＝１２０Ｋｂｐｓ ＲＬ＝３ｋΩ ７．０ Ｖｃｃ＝５．５Ｖ ６．５ １２ ＳＬＥＷ ＲＡＴＥ（Ｖ／ｕＳ） ＶＯＨ、－ＶＯＬ（Ｖ） ７．５ Ｖｃｃ＝５．０Ｖ ６．０ ＡＬＬ ＴＲＡＮＳＭＩＴＴＥＲＳ ＬＯＡＤＥＤ ＤＡＴＡ ＲＡＴＥ＝１２０Ｋｂｐｓ ＲＬ＝３ｋΩ １０ ８ －ＳＬＥＷ ＲＡＴＥ ６ ＋ＳＬＥＷ ＲＡＴＥ ４ ５．５ Ｖｃｃ＝４．５Ｖ ２ ５．０ ０ １０００ ２０００ ３０００ ４０００ ＬＯＡＤ ＣＡＰＡＣＩＴＡＮＣＥ（ｐＦ） STC232E Datasheet Rev.0.1, Dec.2005 ５０００ ０ １０００ ２０００ ３０００ ４０００ ５０００ ＬＯＡＤ ＣＡＰＡＣＩＴＡＮＣＥ（ｐＦ） Page ３ of 6 STC International Limited http://www.mcu-memory.com Test Circuits ＋５Ｖ ０．１ｕＦ ０．１ｕＦ ０．１ｕＦ + + Ｖｃｃ Ｃ１＋ + Ｃ１－ ＋５Ｖ ０．１ｕＦ Ｖ＋ ＳＴＣ２３２Ｅ Ｖ－ ０．１ｕＦ ０．１ｕＦ Ｃ２－ Ｔ＿ＩＮ Ｒ＿ＯＵＴ ０．１ｕＦ ４００Ｋ Ｔ＿ Ｔ＿ＯＵＴ Ｒ＿ + Ｒ＿ＩＮ + Ｖｃｃ Ｃ１＋ Ｃ１－ + Ｃ２＋ Ｖｃｃ + + + ＳＴＣ２３２Ｅ Ｖ－ ２５００ｐＦ Ｃ２－ + ４００Ｋ Ｔ＿ Ｒ＿ Ｒ＿ＯＵＴ Ｔ＿ＯＵＴ Ｒ＿ＩＮ ７Ｋ ５０ｐＦ ５Ｋ ５Ｋ ＭＩＮＩＭＵＮ ＳＬＥＷ－ＲＡＴＥ ＴＥＳＴ ＣＩＲＣＵＩＴ ０．１ｕＦ Ｃ２＋ Ｖｃｃ Ｔ＿ＩＮ ３Ｋ Ｖ＋ ＭＡＸＩＭＵＭ ＳＬＥＷ－ＲＡＴＥ ＴＥＳＴ ＣＩＲＣＵＩＴ ＴＲＡＮＳＭＩＴＴＥＲ ＩＮＰＵＴ ＰＵＬＬ－ＵＰ ＲＥＳＩＳＴＯＲＳ Figure 1. Transition Slew-Rate Circuit Detailed Description The STC232E consists of three sections: charge-pump voltage converters, drivers, and receivers. These E versions provide extra protection against ESD. They survive ±15kV discharges to the RS-232 inputs and outputs, tested using the Human Body Model. When tested according to IEC1000-4-2, they survive ±8kV contact-discharges and ±15kV air-gap discharges. The rugged E versions are intended for use in harsh environments or applications where the RS-232 connection is frequently changed. The STC232E devices have internal charge pump voltage converters which allow them to operate from a single +5V supply. The charge pumps will operate with polarized or non-polarized capacitors ranging from 0.1 to 10 µF and will generate the ±9V needed to generate the RS-232 output levels. Capacitor Selection The capacitor type used for C1–C4 is not critical for proper operation. The STC232E require 0.1 µF capacitors, although capacitors up to 10 µF can be used without harm. Ceramic dielectrics are suggested for the 0.1 µF capacitors. When using the minimum recommended capacitor values. If in doubt, use capacitors with a large (e.g.,2X) nominal value. The effective series resistance (ESR) of capacitors, which usually rises at low temperatures, influences the amount of ripple on V+ and V-. Use larger capacitors (up to 10 X) to reduce the output impedance at V+ and V-. Bypass VCC to ground with at least 0.1 µF. In applications sensitive to power-supply noise generated by the charge pumps, decouple VCC to ground with a capacitor the same size as (or larger than) the charge-pump capacitors (C1–C4). RS-232 Drivers The drivers are inverting transmitters, which accept TTL or CMOS inputs and output the RS-232 signals with an inverted sense relative to the input logic levels. Typically the RS-232 output voltage swing is 9V. Even under worst case loading conditions of 3kO and 2500pF, the output is guaranteed to be 5V, which is consistent with the RS-232 standard specifications. The transmitter outputs are protected against infinite short-circuits to ground without degradation in reliability. The instantaneous slew rate of the transmitter output is internally limited to a maximum of 30V/µs in order to meet the standards [EIA RS-232-D 2.1.7, Paragraph (5)]. However, the transition region slew rate of these enhanced products is typically 10V/µs. The smooth transition of the loaded output from VOL to VOH clearly meets the monotonicity requirements of the standard [EIA RS-232-D 2.1.7, Paragraphs (1) & (2)]. STC232E Datasheet Rev.0.1, Dec.2005 Page ４ of 6 STC International Limited http://www.mcu-memory.com RS-232 Receivers The receivers convert RS-232 input signals to inverted TTL signals. Since the input is usually from a transmission line, where long cable lengths and system interference can degrade the signal, the inputs have a typical hysteresis margin of 500mV. This ensures that the receiver is virtually immune to noisy transmission lines. The input thresholds are 0.8V minimum and 2.4V maximum, again well within the 3V RS-232 requirements. The receiver inputs are also protected against voltage up to 25V. Should an input be left unconnected, a 5kO pull down resistor to ground will commit the output of the receiver to a high state. In actual system applications, it is quite possible for signals to be applied to the receiver inputs before power is applied the receiver circuitry. This occurs, for example, when a PC user attempts to print, only to realize the printer wasn’t turned on. In this case an RS-232 signal from the PC will appear on the receiver input at the printer. When the printer power is turned on, the receiver will operate normally. All of these enhanced devices are fully protected. ESD Protection STC232E devices have standard ESD protection structures incorporated on the pins to protect against electrostatic discharges encountered during assembly and handling. In addition, the RS232 bus pins (driver outputs and receiver input) of these devices have an extra level of ESD protection. Advanced ESD structures were designed to successfully protect these pins against ESD discharge of 15kV when powered down. Pin Configurations and Typical Operating Circuits ＋５Ｖ ＩＮＰＵＴ ＴＯＰ ＶＩＥＷ Ｃ５ Ｃ１＋ １ １６ Ｖｃｃ Ｖ＋ ２ １５ ＧＮＤ Ｃ１－ ３ １４ Ｔ１ＯＵＴ Ｃ２＋ ４ ＳＴＣ２３２Ｅ Ｃ２ １３ Ｒ１ＩＮ Ｃ２－ ５ １２ Ｒ１ＯＵＴ Ｖ－ ６ １１ Ｔ１ＩＮ Ｔ２ＯＵＴ ７ １０ Ｖ２ＩＮ Ｒ２ＩＮ ８ Ｃ１ ＴＴＬ／ＣＭＯＳ ＩＮＰＵＴＳ ９ Ｒ２ＯＵＴ ＤＩＰ／ＳＯ １ + ３ ４ + ５ + １６ Ｖｃｃ Ｃ１＋ ＋５Ｖ ＴＯ ＋１０Ｖ Ｃ１－ ＶＯＬＴＡＧＥ ＤＯＵＢＬＥＲ Ｖ＋ ２ ＋１０Ｖ Ｃ２＋ ＋１０Ｖ ＴＯ －１０Ｖ ６ －１０Ｖ Ｖ－ Ｃ２－ ＶＯＬＴＡＧＥ ＩＮＶＥＲＴＥＲ Ｃ４ + ＋５Ｖ ４００ＫΩ １１ Ｔ１ＩＮ Ｔ１ＯＵＴ １４ ＋５Ｖ ＲＳ－２３２ ４００ＫΩ ＯＵＴＰＵＴＳ １０ Ｔ２ＩＮ Ｔ２ＯＵＴ ７ １２ Ｒ１ＯＵＴ ＴＴＬ／ＣＭＯＳ ＯＵＴＰＵＴＳ Ｃ３ + Ｒ１ＩＮ １３ ５ＫΩ ９ Ｒ２ＯＵＴ Ｒ２ＩＮ ８ ＲＳ－２３２ ＩＮＰＵＴＳ ５ＫΩ ＧＮＤ １５ STC232E Datasheet Rev.0.1, Dec.2005 Page ５ of 6 STC International Limited http://www.mcu-memory.com Package Information Ｐｈｙｓｉｃａｌ Ｄｉｍｅｎｓｉｏｎｓ Ｉｎｃｈｅｓ （ｍｉｌｌｉｍｅｔｅｒｓ）ｕｎｌｅｓｓ ｏｔｈｅｒｗｉｓｅ ｎｏｔｅｄ ０．３８６－０．３９４ （９．８０４－１０．００） １６ １５ １４ １３ １２ １１ １０ ９ ０．２２８－０．２４４ （５．７９１－６．１９８） ＬＥＡＤ ＮＯ．１ ＩＤＥＮＴ ３０° ＴＹＰ １ ２ ３ ４ ５ ６ ７ ８ ０．０１０ ＭＡＸ ０．２５４ ０．１５０－０．１５７ （３．８１０－３．９８８） ０．０１０－０．０２０ （０．２５４－０．５０８） ０．０５３－０．０６９ ×４５° （１．３４５－１．７５３） ８°ＭＡＸ ＴＹＰ ０．００４－０．０１０ ＡＬＬ ＬＥＡＤＳ （０．１０２－０．２５４） ＳＥＮＴＩＮＧ ＰＬＡＮＥ ０．００８－０．０１０ ０．０１４ ０．０１６－０．０５０ （０．２０３－０．２５４） （０．３５６） （０．４０６－１．２７０） ＴＹＰ ＡＬＬ ＬＥＡＤＳ ０．０５０ ０．０１４－０．０２０ ＴＹＰ （１．２７０） ＴＹＰ ＴＹＰ ＡＬＬ ＬＥＡＤＳ （０．３５６－０．５０８） ０．００８ （０．２０３） ０．７４０－０．７８０ ０．０９０ （１８．８０－１９．８１） （２．２８６） １６ １５ １４ １３ １２ ＴＹＰ １１ １０ ９ ＩＮＤＥＸ ＡＲＥＡ １６ １５ １４ １３ １２ １ ２ ３ ４ ５ １１ １０ ９ ６ ７ ８ ０．２５０±０．０１０ （６．３５０±０．２５４） ＰＩＮ ＮＯ．１ ＩＤＥＮＴ １ ２ ３ ４ ５ ６ ７ ＰＩＮ ＮＯ．１ ＩＤＥＮＴ ８ ＯＰＴＩＯＮ ０１ ０．１３０±０．００５ （３．３０２±０．１２７） ０．０６０ ＴＹＰ （１．５２４） ＯＰＴＩＯＮ ０２ ０．０６５ ４°ＴＹＰ ０．３００－０．３２０ （１．６５１） ＯＰＴＩＯＮＡＬ （７．６２０－８．１２８） ０．１４５－０．２００ （３．６８３－５．０８０） ９０°±４°ＴＹＰ ０．０２０ ＭＩＮ （０．５０８） ０．１２５－０．１５０ ０．０３０±０．０１５ （３．１７５－３．８１０） （０．７６２±０．３８１） ０．１００±０．０１０ ０．０１４－０．０２３ （０．３５６－０．５８４） ＴＹＰ STC232E Datasheet Rev.0.1, Dec.2005 ０．０５０±０．０１０ （１．２７０±０．２５４） ＴＹＰ （２．５４０±０．２５４） ＴＹＰ ９５°± ５° ０．２８０ ０．００８－０．０１６ （０．２０３－０．４０６） ＴＹＰ （７．１１２） ＭＩＮ ０．３２５ ＋０．０４０ －０．０１５ ８．２５５ ＋１．０１６ －０．３８１ Ｎ１ＲＥ（ＲＥＶ Ｆ） Page ６ of 6