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19-1104 Rev 0 7 / 96

MAX117 Evaluation Kit

19-1104 Rev 0 7 / 96
MAX117 Evaluation Kit
The MAX117 evaluation kit (EV kit) is a fully assembled evaluation board for the 8-bit, 8-channel, +3V MAX117 analog-to-digital converter. Channel selection can be controlled by switches located on the board or by userprovided logic-level signals. An on-board oscillator provides continuous conversions, and the conversion results appear on the LED output display. The MAX117 EV kit also evaluates the +5V MAX118. To evaluate the MAX118, order a MAX118 free sample, replace the MAX117 with the MAX118, and install the appropriate R9 resistor (see Component List).
o +3V (MAX117) or +5V (MAX118) Operation o Fully Assembled and Tested o On-Board Oscillator Generates Timing Signals o LED Display of Conversion Results o Low-Power Shutdown Mode
Evaluates: MAX117 / MAX118
DESIGNATION QTY C1, C4 C2, C5-C8 C3 J1 JU1, JU4 JU2, JU3, JU5-JU8 LED1-LED8 N1 R1, R2, R3, R5, R6 R4, R7, R8 2 5 1 1 2 6 8 1 5 3 DESCRIPTION 22µF, 10V electrolytic capacitors 0.1µF, 50V ceramic capacitors 1000pF, 50V ceramic capacitor 20-pin ribbon-cable connector 3-pin jumper headers 2-pin jumper headers Red LEDs Low-RDS(ON), N-channel FET International Rectifier IRML2402 100k resistors 10k resistors 330, 10-pin SIP resistor (installed, used with MAX117) R9 1 560, 10-pin SIP resistor (not installed, used with MAX118) R10 SW1 U1 U2 U3 None None None 1 1 1 1 1 8 1 4 5.1k resistor 4-position DIP switch MAX117CPI 74HC564 inverting 8-bit latch 74HC04 hex inverter Shunts Printed circuit board Rubber feet
PART MAX117EVKIT-DIP TEMP. RANGE 0°C to +70°C BOARD TYPE Through Hole
Note: To evaluate the MAX118, request a MAX118CPI free sample.
Verify operation of the MAX117 evaluation board by configuring for continuous conversions using the onboard oscillator. Take the following steps: 1) Verify that the jumpers are configured as shown in Table 1. 2) Connect a +3V, 100mA supply to the VDD pad. A 20mA supply is sufficient if the LED output display is disabled. To evaluate the MAX118, use a +5V supply and replace the 330, 10-pin SIP resistor (R9) with the 560 SIP resistor included in the kit. 3) Connect an input signal to the AIN1 input pad. 4) On switch SW1, set A0, A1, and A2 to the on position and set PD to the off position (Table 3). 5) Observe the conversion results on the LED display as the input voltage is varied between ground and the supply voltage.
International Rectifier: (310) 322-3331
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800
MAX117 Evaluation Kit Evaluates: MAX117 / MAX118
Table 1. Jumper Configuration for Continuous-Conversion Operation
Shutdown
JU2 JU3 JU4
Open Shorted 2&3
Shorted
Current Measurement
The current supplied to the board includes the current drawn by the MAX117, the on-board oscillator, the output latch, and the LED display. Jumper JU5 is in series with the MAX117 VDD pin to facilitate MAX117 supplycurrent measurements. Measure the MAX117 supply current or shutdown current by removing the shunt that normally shorts JU5, and connecting an ammeter across the two jumper pins. Refer to Table 2 for the appropriate jumper / switch settings.
JU6 JU7 JU8
Shorted Shorted Shorted
MAX117 Reference Voltage
The MAX117 reference can be connected to any voltage between VDD and ground (VREF+ VREF-). To use the power-supply rails as the reference voltage, short jumper JU7 and install a shunt on JU1 (in either position). When using an external reference, remove the shunts from JU1 and JU7, and apply your external reference source to the VREF+ and VREF- pads.
Table 2. Jumper / Switch Settings for MAX117 Current Measurements
Off On
Continuous Conversions
A 74HC04, configured as a free-running oscillator, provides the continuous-conversion signals (CS and RD) on the evaluation board. The oscillator output also clocks the MAX117 conversion results into a 74HC564 octal latch for display by eight LEDs. The oscillator must be disconnected when the MAX117 is controlled by external circuitry. Remove the shunts from jumpers JU4, JU6, and JU8 to disconnect the on-board oscillator. For additional flexibility, the digital signals and data outputs are available at the 20-pin connector, J1.
MAX117 Evaluation Kit
Table 3. Jumper Functions
Jumper Selections
Jumpers JU1-JU8 allow the user various configuration options for the EV kit. Table 3 lists the various jumper functions.
Evaluates: MAX117 / MAX118
Switch Selections
The four-position DIP switch (SW1) is used to select an input channel and to enable / disable power-down mode. The address pins (A0-A2) and the power-down pin (PWRDN) are pulled up to VDD through a 100k resistor. These pins are connected to ground when the associated switch (A0, A1, A2, or PD) is in the on position. The switches must be in the off position for external logic to control input-channel selection or powerdown mode.
Table 4. SW1 DIP Switch Selections
A0 On Off On Off On Off On A1 On On Off Off On On Off A2 On On On On Off Off Off
Off Off Off Off Off Off Off IN1 IN2 IN3 IN4 IN5 IN6 IN7
INPUT CHANNEL
Open JU5 Shorted Open JU6 Shorted Open JU7 Shorted Open JU8 Shorted
IN8, analog input internally connected to REF+ or channel selection controlled externally. The MAX117 is in shutdown (PWRDN grounded).
Evaluates: MAX117 / MAX118
MAX117 Evaluation Kit
Figure 1. MAX117 EV Kit Schematic
VDD + C4 22µF VDD R6 100k JU3 LEDs LED1 2 3 4 5 6 7 LED2 D0 8 J1-5 J1-6 LED4 19 LED5 LED6 LED7 8 LED8 9 10 13 12
C5 0.1µF JU5 VDD 27 IN1 IN3 D2 J1-8 J1-9 J1-10 J1-11 J1-12 J1-14 VDD JU2 MODE J1-13 MODE INT J1-3 WR / RDY PWRDN VDD REF+ RD J1-7 REFCS GND 1 JU4 CS J1-1 J1-2 GND GND 2 3 14 18 CS JU6 RD 12 R10 5.1k J1-15 6 RD 74HC04 R7 10k 8 U3D 74HC04 9 74HC04 R8 10k 74HC04 C3 1000pF JU8 WR / RDY WR / RDY U3C 5 4 U3B 3 2 U3A 1 17 J1-4 11 MODE VDD 23 JU7 REF+ 26 16 + C1 22µF 15 1 R5 100k 3 R4 1 10k PD N1 IRLML2402 2 JU1 REF2 3 C2 0.1µF A2 INT 13 7 D3 D4 D5 VDD 25 A0 D6 21 22 J1-17 A1 VDD 24 A1 R2 100k 20 19 11 10 IN5 IN7 A0 R1 J1-18 100k 18 17 16 15 14 13 12 D1 9 1 U2 LED3 6 IN1 5 IN2 VDD C6 0.1µF J1-20 J1-19 VDD R9 330 FOR 3V 560 FOR 5V 1 4 IN3 3 IN4 2 IN5 1 IN6 28 IN7 11 2 3 4 5 6 7 8 9 Q0 Q1 Q2 Q3 Q4 Q5 Q6 Q7 74HC564 0E CLK D0 D1 D2 D3 D4 D5 D6 D7
U1 MAX117
A1 A2 J1-16 R3 100k
U3F 74HC04 10 U3E 74HC04 C7 0.1µF
VDD C8 0.1µF
PWRDN REF+
REFVDD
MAX117 Evaluation Kit Evaluates: MAX117 / MAX118
Figure 2. MAX117 EV Kit Component Placement Guide-Component Side
MAX117 Evaluation Kit Evaluates: MAX117 / MAX118
Figure 3. MAX117 EV Kit PC Board Layout-Component Side
MAX117 Evaluation Kit Evaluates: MAX117 / MAX118
Figure 4. MAX117 EV Kit PC Board Layout-Solder Side
MAX117 Evaluation Kit Evaluates: MAX117 / MAX118
NOTES
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.