SP306 Corporation SIGNAL PROCESSING EXCELLENCE RS-422/RS-423 Line Drivers/Receivers ■ Single chip serial transceiver supports RS-422 or RS-423 interfaces ■ Programmable Selection of Interface ■ Two Full–Duplex Channels of Either Interface ■ Software–Selectable Mode ■ Loopback for Self–Testing ■ Short–Circuit Protected ■ Surface Mount Packaging DESCRIPTION… The SP306 is a single chip device that offers both RS-422 and RS-423–type serial interfaces. The device can be programmed to provide two full–duplex channels of either RS-422 or RS-423 via two mode control pins. The SP306 also features a loopback function that can be activated in any operating mode. The SP306 is available in a 28–pin SOIC package for operation over the commercial temperature range. SUPPLY +5V +12V –12V 28 1 15 VCC VDD VEE 7 8 22 TINA TINB SELECT A SELECT B LOOPBACK 6 23 T1 9 20 T2 SP306 ROUTA ROUTB 26 Corporation SIGNAL PROCESSING EXCELLENCE 10 2 R1 3 R2 12 13 17 14 5 TOUTA1 TOUTA2 TOUTB1 TOUTB2 RINA2 RINA1 RINB2 RINB1 GND 89 SPECIFICATIONS (TMIN ≤T A ≤T MAX and nominal supply voltages unless otherwise noted) PARAMETER RS-423 DRIVER TTL Input Level VIL VIH High Level Output MIN. Low Level Output –3.0 TYP. 0 2.0 +3.0 Short Circuit Current Transition Time Maximum Transmission Rate 100 RS-423 RECEIVER Input Threshold –200 Input Impedance 4 TTL Output Level VOL VOH 2.4 Maximum Receiving Rate 100 RS-422 DRIVER TTL Input Level VIL 0 VIH 2.0 High Level Output +2.75 Low Level Output Differential Output ±2.0 MAX. 0.8 +6.0 (VDD – 0.7V) –6.0 (VEE +0.7V) ±40 720 +200 0.4 V V V V V V mA ns kbps mV kΩ V V kbps CONDITIONS RL = 450Ω, VIN = 0.8V; Note 6 RL = ∞ RL = 450Ω, VIN = 2.0V; Note 6 RL = ∞ VOUT = 0V; Note 2 RL = 450Ω, CL = 50pF; Note 3 Common–mode = ±7V; Note 1 RIN = ±10V VCC =+4.75V, IOUT =+1.6mA VCC =+4.75V, IOUT =-0.5mA Note 3 0.8 +6 +1.0 ±6.0 Short Circuit Current ±100 Output Current ±500 Transition Time 400 Maximum Transmission Rate 500 RS-422 RECEIVER Common Mode Range ±7 Differential Input ±15 Differential Input Threshold –0.2 +0.2 Input Voltage Hysteresis 30 Input Resistance 3 TTL Output Level VOL 0.4 VOH 2.4 Maximum Receiving Rate 500 Short Circuit Output Current ±120 POWER REQUIREIMENTS VDD = +12V 7 15 VCC = +5V 5 7 VEE = –12V 11 20 ENVIRONMENTAL AND MECHANICAL Operating Temperature –C 0 +70 –M –55 +125 Storage Temperature –65 +150 Package –C 28–pin SOIC –F 28–pin Ceramic Flatpack 90 UNIT V V V V V V mA µA ns kbps V V V mV kΩ V V kbps mA mA mA mA IOH = –20mA IOL = 20mA RL = 100Ω RL = ∞ –0.25V ≤ VO ≤ 6V; Power off RL =450Ω, CL =15pF; Note 3 Note 4 Note 4 TA=25°C VCM =0V;TA=25°C –7V≤VCM≤+7V VCC =+4.75V, IOUT=+1.6mA VCC =+4.75V, IOUT=–0.5mA VOUT=0V All Transmitter outputs RL=∞ TA=25°C °C °C °C Corporation SIGNAL PROCESSING EXCELLENCE Note: 1. The common mode voltage is defined as the algebraic mean of the two voltages appearing at the receiver input terminals with respect to the receiver circuit ground. 2. Only one output drive pin per package will be shorted at any time. 3. From 10% to 90% of steady state. 4. This is an absolute maximum rating. Normal operating levels are VIN ≤ 5V. 5. Outputs unloaded. Inputs tied to GND; TA =+25°C; VIL = 0V; LB = 0. 6. VOL/VOH will typically be ±3V over –55°C to +125°C with 450Ω loads. PINOUT VDD 1 28 VCC RINA2 2 27 N.C. RINA1 3 26 ROUTA N.C. 4 25 N.C. TOUTA2 5 24 N.C. TOUTA1 6 23 TINA SELECTA 7 SELECTB 8 21 N.C. TOUTB1 9 20 TINB TOUTB2 10 19 N.C. N.C. 11 18 N.C. SP306 22 LOOPBACK RINB1 12 17 ROUTB RINB2 13 16 N.C. GND 14 15 VEE PIN ASSIGNMENTS Pin 1 — VDD — +12V Power Supply. Pin 2 — RINA2 — RS422 input. Pin 3 — RINA1 — RS422/RS423 input. Pin 4 — N.C. — No Connection. Pin 5 — TOUTA2 —RS422 output. Pin 6 — TOUTA1 — RS422/RS423 output. Pin 7 — SEL A — Select A; used with Select B (pin 8) to select operating mode; please refer to SP306 Control Logic Configuration section for truth table. Pin 8 — SEL B — Select B; used with Select A (pin 7) to select operating mode; please refer to SP306 Control Logic Configuration section for truth table. Pin 9— TOUTB1— RS422/RS423 output. Pin 10 — TOUTB2 — RS422 output. Pin 11 — N.C. — No Connection. Pin 12— RINB1— RS422/RS423 input. Corporation SIGNAL PROCESSING EXCELLENCE Pin 13 — RINB2— RS422 input Pin 14 — GND — Signal ground. Connected to logic and chasis ground. Pin 15 — VEE — –12V Power Supply. Pin 16 — N.C. — No Connection. Pin 17 — ROUTB — TTL output. Pin 18 — N.C. — No Connection. Pin 19 — N.C. — No Connection. Pin 20 — TINB — TTL input. Pin 21 — N.C. — No Connection. Pin 22 — LOOPBACK — Active low; logic “1” selects operating mode controlled by SELECT A and SELECT B; logic “0” selects loopback configuration for whatever operating mode is selected by states of SELECT A and SELECT B. Pin 23 — TINA — TTL input. Pin 24 — N.C. — No Connection. Pin 25 — N.C. — No Connection. Pin 26 — ROUTA — TTL output. Pin 27 — N.C. — No Connection. Pin 28 — VCC — +5V Power Supply. FEATURES… The SP306 is a single chip device that offers both RS-422 and RS-423 serial interfaces. The device can be programmed via two control mode pins (7 and 8). In either operating mode, the SP306 provides two full–duplex channels. A loopback function is also provided for chip self– test, which connects driver outputs to receiver inputs with no external circuitry. The RS-422 drivers convert TTL logic levels into RS-422 differential output signals. The RS-422 line driver outputs feature high source 91 and sink current capability. The RS423 line drivers convert TTL logic levels into inverted RS-423 output signals. All line drivers are internally protected against short circuits on their outputs. the signal path is non–inverting from the TTL driver inputs to the receiver TTL outputs. This operating mode allows the controlling system to perform diagnostic self–test of the RS-422/ RS-423 transceiver circuitry at speeds up to 3kbps. The RS-422 receivers convert the RS-422 differential input signals into non–inverted TTL logic levels. Receiver input thresholds are ±200mV. The RS-422 receivers can receive input data up to 1Mbps. The RS-423 receivers convert the RS-423 input signals into inverted TTL output logic levels. The RS-423 receivers have an input threshold of ±200mV, and can receive data up to 100kbps. APPLICATION INFORMATION Control Logic Configuration Software control of the SP306 is via two select pins (7 and 8) and a loopback control pin (22). SELECT A and SELECT B allow the user to program the SP306 for four different interface modes. Loopback mode can be selected in any of these interface modes. The figures that follow outline the various operating modes that are supported by the SP306. A loopback test mode is provided that puts the driver outputs into a high impedance tri–state level, and routes the driver outputs to their associated receiver inputs. In this configuration, SELECT A = 0 SELECT B = 0 LOOPBACK = 1 SUPPLY +5V +12V –12V SUPPLY +5V +12V –12V 28 1 15 VCC VDD VEE 28 1 15 VCC VDD VEE 7 8 22 SELECT A SELECT A = 0 SELECT B SELECT B = 0 LOOPBACK TOUTA1 LOOPBACK = 0 TINA ROUTA RINA1 TOUTB1 TINB ROUTB RINB1 14 GND RS-423 DRIVER * Tri–state output 7 8 22 SELECT B LOOPBACK TOUTA*1 TINA ROUTA RINA1 TOUTB*1 TINB ROUTB RINB1 14 SP306 RS-423 RECEIVER SELECT A GND RS-422 RECEIVER SP306 RS-422 DRIVER * Tri–state output Figure 1. Control Input Configuration — SELECT A = 0, SELECT B = 0 92 Corporation SIGNAL PROCESSING EXCELLENCE 7 SELECT A = 0 8 SELECT B = 1 22 LOOPBACK = 1 SUPPLY +5V +12V –12V SUPPLY +5V +12V –12V 28 1 15 VCC VDD VEE 28 1 15 VCC VDD VEE SELECT A SELECT A = 0 SELECT B SELECT B = 1 ROUTA RINA1 RINB2 TOUTB1 RS-423 DRIVER * Tri–state output TINA ROUTA RINB2 ROUTB RINB1 TOUTB*1 TINB TOUTB2 SELECT B LOOPBACK RINA1 ROUTB RINB1 SELECT A TOUTA*1 TINA GND 22 LOOPBACK = 0 LOOPBACK TOUTA1 14 7 8 TINB TOUTB*2 14 SP306 RS-423 RECEIVER GND SP306 RS-422 RECEIVER RS-422 DRIVER * Tri–state output Figure 2. Control Input Configuration — SELECT A = 0, SELECT B = 1 SELECT A = 1 SELECT B = 0 LOOPBACK = 1 7 8 22 SUPPLY +5V +12V –12V SUPPLY +5V +12V –12V 28 1 15 VCC VDD VEE 28 1 15 VCC VDD VEE SELECT A SELECT A = 1 SELECT B SELECT B = 0 LOOPBACK RINA2 LOOPBACK = 0 ROUTA RINA1 TOUTA1 TINA TOUTA2 TOUTB 1 TINB ROUTB RINB1 14 GND RS-423 DRIVER * Tri–state output 7 8 22 SELECT B LOOPBACK RINA2 ROUTA RINA1 TOUTA*1 TINA TOUTA*2 TOUTB *1 TINB ROUTB RINB1 14 SP306 RS-423 RECEIVER SELECT A GND RS-422 RECEIVER SP306 RS-422 DRIVER * Tri–state output Figure 3. Control Input Configuration — SELECT A = 1, SELECT B = 0 Corporation SIGNAL PROCESSING EXCELLENCE 93 SUPPLY +5V +12V –12V SUPPLY +5V +12V –12V 28 1 15 VCC VDD VEE SELECT A = 1 SELECT B = 1 LOOPBACK = 1 7 8 22 28 1 15 VCC VDD VEE SELECT A SELECT A = 1 SELECT B SELECT B = 1 LOOPBACK RINA2 LOOPBACK = 0 ROUTA RINA1 TOUTA1 TINA TOUTA2 RINB2 ROUTB RINB1 TOUTB1 TINB TOUTB2 14 GND RS-423 DRIVER * Tri–state output 7 8 22 SELECT B LOOPBACK RINA2 ROUTA RINA1 TOUTA*1 TINA TOUTA*2 RINB2 ROUTB RINB1 TOUTB*1 TINB TOUTB*2 14 SP306 RS-423 RECEIVER SELECT A GND RS-422 RECEIVER SP306 RS-422 DRIVER * Tri–state output Figure 4. Control Input Configuration — SELECT A = 1, SELECT B = 1 ORDERING INFORMATION Model Temperature Range Package Two full–duplex channels RS-422/RS-423 SP306CT ................................................ 0°C to +70°C ............................................................... 28–pin SOIC SP306MF .......................................... –55°C to +125°C ........................................... 28–pin Ceramic Flatpack 94 Corporation SIGNAL PROCESSING EXCELLENCE